23 ms·

‘Anti-hunger’ molecule forms after exercise, scientists discover

289 points by echen 4y ago

davidkuennen 4y ago
Also anecdata. Whenever I'm exercising I know that I won't be hungry afterwards even if I was before. I always thought it was strange.
ianbutler 4y ago
With cardio I’m more hungry later in the day but weight lifting, not only do I get a better workout I have less cravings for junk and my hunger is way less.
arcticbull 4y ago
And yet folks who exercise also end up having acute compensatory eating. [1] Your body is designed to maintain homeostasis. Exercise is not how you lose weight, changing your diet up to and including fasting is. Exercise is good for you in a whole lot of other ways, but the idea you can outrun a bad diet is pretty thoroughly debunked at this point. [1] https://pubmed.ncbi.nlm.nih.gov/19419671/ https://pubmed.ncbi.nlm.nih.gov/19419671/
- hardwaresofton 4y ago
  Agreed on all points, but just want to point out that it would be ideal if you could supplement dieting with effective hunger suppression though —- their work towards isolating lactate and phenylalanine as signals towards hunger suppression is pretty impressive if it can give a foothold in that area.
- benreesman 4y ago
  You sound knowledgeable about this: I personally find that even when I’m having trouble controlling caloric intake as well as I’d like that sharp reductions in simple carbohydrates and sugars seem to help with weight loss even if my envelope math seems to indicate comparable total calories? Is this just bad measurement or is there anything to that?
  - make3 4y ago
    research show that people are apparently terrible at evaluating how many calories they take, even dieticians. by cutting more addictive food, it's possible that you're actually eating less than your otherwise would, even if the numbers don't seem to add up
  - bavell 4y ago
    Sounds to me like it's due to the ease of digesting simple carbs vs complex carbs, which require more digestion to process. I think with complex carbs your net calories gained are actually lower than what the nutrition label says since they require some amount of calories to digest.
- elwesties 4y ago
  It’s funny, they way I describe the relationship I have with weight loss is exercise is that the exercise is giving you the reason to eat clean. You won’t want to make that effort worth nothing. It’s not the same for everyone but I certainly notice it
  - cehrlich 4y ago
    This is my experience as well. Going on a long run if you ate garbage the day before feels terrible, so you get conditioned to eat clean.
  - Der_Einzige 4y ago
    Hahaha what? Sorry, but the term dirty bulking, and the existence of "eat big to get big" videos among the body builder community shows that many in the high end to elite strata of weight training not only just don't eat clean, but they also get their enjoyment and muscle from the absolutely nasty food they eat as part of it (... Yes and roids) https://youtu.be/PX33LjIMQoA https://youtu.be/PX33LjIMQoA
- dhedberg 4y ago
  For me personally I have noticed that exercising helps me by modulating my food cravings. I'll get hungry of course, but in a way where I'm more happy just eating some reasonable amount of actual food instead of stuffing myself with a bag of crisps or worse. This might also be psychological; it feels good after exercising so I feel more inclined to stay on the path. The result, either way, is that while I know from experience that just changing my diet works to lose weight, it becomes a lot easier to keep it up when also exercising.
- paskozdilar 4y ago
  > Exercise is good for you in a whole lot of other ways, but the idea you can outrun a bad diet is pretty thoroughly debunked at this point. Perhaps you can't "outrun" a bad diet, but you can certainly out-lift it. Weight training leads to stronger muscles, stronger muscles spend more energy, more energy spent leads to losing weight.
  - arcticbull 4y ago
    This is another one of those fun little half-truths. > 10 pounds of muscle would burn 50 calories in a day spent at rest, while 10 pounds of fat would burn 20 calories [1] 50 pounds of fat burns 100 calories per day. 10 pounds of muscle burns 50 calories per day. If you lose 50 pounds of fat and replace it with 10 pounds of muscle, you're net 50 calories per day. About 1/10th of a Starbucks muffin. Not eating a Starbucks muffin is the same as having 90 extra pounds of muscle. You'd have to look like John Cena for this to make any difference whatsoever. But you're never going to look like John Cena unless you adjust your diet. The only way to lose fat is to change your diet. [1] https://www.webmd.com/diet/obesity/features/8-ways-to-burn-calories-and-fight-fat https://www.webmd.com/diet/obesity/features/8-ways-to-burn-c...
    - paskozdilar 4y ago
      > at rest Who said anything about resting? I'm talking about exercise. The more you exercise, the more muscle you build, which makes you spend more energy while exercising. Do you have any idea how much bodybuilders eat, without gaining any significant fat? > The only way to lose fat is to change your diet. False. You can lose fat by exercising, without changing your diet whatsoever.
      - arcticbull 4y ago
        > Who said anything about resting? I'm talking about exercise. The more you exercise, the more muscle you build, which makes you spend more energy while exercising. Again muscle vs fat don't change significantly that quantity of calories burned, unless you have some citations. > False. You can lose fat by exercising, without changing your diet whatsoever. Not in any practical sense. Most folks don't have the time to run a five-miler for each muffin they eat in a given day. This advice is just not useful. It's technically correct but totally unhelpful. It's basically the tautology: 'once you've lost weight you've lost weight.'
- glenngillen 4y ago
  I’d heard this for years and was quite the skeptic. I’d hit the gym pretty consistently in my late teens and cycled a lot and kept a pretty consistent weight irrespective of what I ate. Over the better part of 20 years the only real fluctuations were during extended travel periods where both diet was bad and exercise non-existent. But multiple marathons, extended focus on weight training, picking up various sports again, and I’d oscillate in about a 3kg range. And then my wife had to go on an extended elimination diet to deal with gastrointestinal issues and I joined as moral support. In the space of a month, with absolutely no exercise happening, I dropped 10kgs. And I don’t think I’d ever felt healthier. As soon as I got back to running I was as quick as I’d ever been, no great surprise I guess given how much lighter I was. Turns out the biggest impact I could have on my health was being more conscious of what I was eating. I couldn’t out run what I was putting in my mouth, no matter the distances I was putting in.
  - joshu 4y ago
    my trainer says “you can’t outrun a cheesburger.” i should probably stop showing up with mcdonalds
    - bennyelv 4y ago
      Anecdata warning - you actually can! The problem with trying to outrun a cheeseburger is that you probably need to be quite fit to do it. It works like this: If you're unfit, your capacity for output during exercise is less. If you're fitter, your capacity for output during exercise is higher. An unfit person doing exercise, will therefore burn significantly fewer calories than someone who is fit if they exercise for the same duration at the same perceived effort. If I go for a hard 1 hour bike ride, I burn 3 cheeseburgers. An unfit person will struggle to burn much more than 1 despite working as hard as they can.
      - count 4y ago
        This seems to run counter to what I see in data based on heart rate at least. As you get more fit, your cardio conditioning level goes up, which means you are substantially more efficient in exercise. When you're not efficient, you'll burn more calories doing the same work.
- asdff 4y ago
  People doubting the power of caloric deficit need to watch Alone. People scarcely bringing in one squirrels-worth of calories a day while laboring around camp are just sloughing off the weight on that show. Some have gotten pulled for medical because they were losing it too fast and stressing their heart. One guy lost 86 pounds in 67 days.
  - xorfish 4y ago
    That is not a good rate to lose weight. A rate of ~1% per week for 3-4 months followed by 1-2 months of maintenance before the next weight loss phase is much more sustainable and you are more likely to not gain back the weight after the target weight is achieved.
    - asdff 4y ago
      Yeah its a terrible way to lose weight, that's why stickies on places like bodybuilding forums encourage a moderate deficit plus exercise to maintain bone and organ health (1). But it goes to show that with a deficit you will shed weight. There is no special sauce in individual metabolism that makes energy from nothing at the end of the day. Losing weight is a matter of thermodynamics. 1. https://forum.bodybuilding.com/showthread.php?t=165843261 https://forum.bodybuilding.com/showthread.php?t=165843261
    - arcticbull 4y ago
      This seems to be folk wisdom, but is it supported by any actual data?
- thesz 4y ago
  As I said elsewhere here, it is not the case for me - I quite often experience food aversion after exercise (weight training). I exercise in fasted state, 14-18 hours of fast. If exercise is especially hard, I found food not attractive at all, neither how it looks or how it smells. I have to force myself to eat when this happen and usually eat less. On bright side, I've found that I recover faster after exercise bouts when I'm in fasted state. I also have to note that was not the case when I was younger and performed my training routines after being fed. When I exercised being fed I experienced hunger and wanted to eat.
veltas 4y ago
I always get a monster appetite after exercise, could just be conditioning. Sample size of one.
- thesz 4y ago
  For several years I exercise in fasting state, 14-18 hours of fasting. I can easily not eat for three hours after exercise. Actually, I experience no hunger at all. Could just be conditioning. Sample size of one.
  - ID1452319 4y ago
    What sort of exercise were you doing fasted? Did you find it impacted your performance?
    - thesz 4y ago
      Weight resistance training, mostly. Also occasional Tabata squats for some endurance. I found that I recover from quite intensive sets faster when training fasted. The decline in performance I experience can be explained by my age and, frankly, that I do not exercise regularly enough.
  - foolfoolz 4y ago
    i think 90% of huger is conditioning. you can train yourself to eat less. you can train yourself to stop being hungry. and it doesn’t take long, maybe a month or so
- asdff 4y ago
  Especially cardio I will actually get faint if I don't keep up with food. On long bike rides I will eat two al pastor tacos every 20 miles from a stand or truck. A lot of those 10/25/50/100 mile charity bike rides have regular stops with peanut butter packets or beer too so riders can get liquid calories and carbs (and a buzz of course).
- idoubtit 4y ago
  After a few hours of intense activity, I'm usually very hungry. But when I walk in the mountains for full days (8-12 hours per day), I don't have much of an appetite, especially after two days. I almost have to force myself to eat a real lunch and dinner, though I tend to frequently eat small quantities of dried fruits.
psiops 4y ago
This would explain why exercise causes weight loss even though people with sedentary and active lifestyles seem to burn the same amount of calories[1] [1] https://dupri.duke.edu/news-events/news/herman-pontzer-explains-where-our-calories-really-go-and-what-studying-humanitys https://dupri.duke.edu/news-events/news/herman-pontzer-expla...
benreesman 4y ago
If this is just me whinging then I apologize, but in my own life and among some people I know: the insane bifurcation into monster fitness where it’s more important than your job and “no one cares” seems to be a driver of careless weight management. The standard of being “in shape” has gotten so absurd, and the nonlinear payoff around fitness so steep at the “maybe doing some pretty extreme shit” cutoff that I’m personally surprised I have t just given up, and it seems a lot of people have. I don’t know if it’s TikTok, or Marvel movies, or whatever: but “fucking mutant superhero” used to one among many attractive archetypes.
- FeaturelessBug 4y ago
  I don't know if my own anecdote will help you but I've been overweight since I was a child and I've done just about every diet under the moon. I used to hate myself and my body, a lot. I went to the gym three days a days week pushing myself hard and counted calories, and my weight wouldn't budge. I ended up developing a lot of disordered eating doing fasting and I really thought I could hate myself into being thin. When I finally found keto and it worked, I started dropping weight and I quickly lost control of my diet and started to starve myself in earnest while continuing what exercise I could. After a while all I could do was take long walks. I lost 80 pounds in 8 months doing this, and I was still considered over weight by about 60 pounds. I never got any happier with myself by changing my body. I still didn't think I was worth anything unless I could get tiny. I had really bad brain fog, I stopped being able to produce my own body heat, started to have fainting spells, and finally heart palpitations. When I went to the doctor all they told me is what a good job I was doing losing weight and that the palpitations were from my panic disorder. I finally stopped keto because my partner sat me down and begged me to stop. It was really hard and it took time to give it up, but I finally did. I had no real muscle left and I was so fatigued... Over the course of a year... I gained all the weight back. I still have palpitations sometimes, and I will never know what damage yoyo dieting for years did to me. I don't diet anymore, I've started intuitive eating and my diet has improved over all. I eat variety now, more vegetables and lots of protein. I also have carbs, and dessert with I want it. I've also started doing things for the experience rather than to make my body look a certain and ultimately unattainable way. I don't focus on how I look anymore, I focus on being strong. I am now highly active and doing activities I never thought I would be capable of in my fat body. I take dance classes four times a week, I lift weights, and I am starting Lyra and aerial classes. I also don't step on scales anymore. But I can tell you I haven't magically shrunk. I guess what I'm trying to say is... Any standard of "in shape" can be impossible for any person. We aren't all meant to look that same and I think that people are caring less about being overweight because it should never have been a limiting factor to you enjoying your life, being active, and being well loved by the right people.
DoreenMichele 4y ago
“We estimate that the lac-phe pathway is responsible for about 25% of the anti-obesity effects of exercise,” Long said. I find this article annoying. It should come as no surprise that there is a mechanism for suppressing appetite during physical activity. There is only so much blood to go around and both digestion and exercise place demands on the blood supply. It would be a hardship to place both demands on the body at the same time consistently.
- have_faith 4y ago
  > I find this article annoying. Why is it annoying? confirming unsurprising results is important.
  - DoreenMichele 4y ago
    Because it's framed like research for a potential weight loss pill rather than research into the mechanism behind the fairly well-known fact that people typically have less appetite while being physically active. I hate the tendency to frame everything in terms of a pill to fix our problems and/or a get rich quick scheme as a substitute for trying to figure out how to live right.
    - vosper 4y ago
      You’re absolutely right about the quality of the submitted article. It’s written like low-grade clickbait tech “journalism”. It’s even worse than the battery-breakthrough-of-the-week university PR pieces that get posted here. I imagine the research is good and useful. Pity about the way it’s been presented.
    - FollowingTheDao 4y ago
      It is actually more important than you thing since it links manganese to metabolic syndrome.
freiherr 4y ago
>Does this finding hold promise for that ever-elusive diet pill? I wonder what will go wrong this time with side-effects. Maybe overeating rebound after it gets out of the system. That would resemble natural compensation of calories after activity is finished. From personal experience I recommend saturated fat (mostly from beef tallow) as an anti-hunger molecule. With as little as possible omega-6 in the diet. And carnivore. Works wonders. My satiety base level is now set so that I get down to ~12% bf in a reasonable time when I'm above that. Could also bulk up to a powerlifting competition on this diet no problem when necessary.
- ddorian43 4y ago
  Yes, just tried bulking on a 6 week program and was very impressed with carnivore.
  - a3w 4y ago
    Meat very slightly causes cancer. Saturated fats reduce your life expectancy, too. Not that good advice I guess?
    - blfr 4y ago
      Check the studies you're relying on for this information. Most are confounded by people simply eating fast food.
      - quickthrower2 4y ago
        And fast food is different because… ?
        blfr 4y ago
        Lots of crappy carbs and added sugar on the side with generally low quality ingredients compared to what anyone caring about their diet would eat. Most people don't have the dedication of a body builder carefully eating only patties from the burgers. Which would probably work.
nonrandomstring 4y ago
The article mentions that a substance (lactose-phenylalanine) appears after exercise in several animal studies. There's a suggestion of a strong connection of this to reduced appetite. But this isn't explained and more importantly there's no hypothesised mechanism. Why would it be a metabolic advantage to reduce hunger after exertion? Maybe it creates a buffer-period. Otherwise, common sense/intuition would say we feel hungrier after exercise. What gives?
- aqme28 4y ago
  My guess is that exercise implies that you're doing something important (fighting, fleeing, etc), and it is not the time to be distracted by hunger.
- otikik 4y ago
  “After” is what happens now, when we are in control of our time “I will hit the gym for one hour”. In our past, physical activity was a survival-related task with no fixed end time (chasing a prey, fleeing from danger). I think for our ancestors it would happen during exertion. It would not be advantageous to feel increasingly hungry while exercising, the same way that it makes sense for adrenaline to block pain during a fight. Less distraction, more survival
  - hinkley 4y ago
    I think it helps if you think of exercise as what it is: lying. A longshoreman is strong because he spends all day shifting cargo around. Steve is big and buff because he tricks his body into thinking shifting cargo around all day is a likely scenario. Muscle is expensive. The body is very stingy with keeping muscle you don't need on a regular basis. A gym visit is trying to simulate the behavior of all-day exertion without having to abandon all of the other activities you want to fill your day with.
- fasteo 4y ago
  >>> Otherwise, common sense/intuition would say we feel hungrier after exercise. What gives? I would hypothesize that recovery and digestion are two metabolically intensive activities that the body is unable to do them simultaneously, so it would make sense to suppress hunger while the body recovers itself from exercise. Now, the supplement industry has made us believe that if you don't consume food within the magical anabolic window, you recovery will be impaired. Nonsense if you ask me.
10x-dev 4y ago
Anecdata: when I was intermittently fasting, I found that exercising at lunch curbed my appetite and I could easily last till dinner with no food or with a small yogurt snack (<50cal). On days when I didn't exercise, I felt hungrier and had to engage my will power much more during the day.
Tade0 4y ago
Now that I am a parent I often eat work for breakfast. I've found that two things cause massive hunger in my case: a diet rich in added sugar/salt and being tired. The latter usually comes after extended exercise, so appears to be counterproductive for weight loss. Other benefits still apply though. Just dropping added sugar/salt now that my child eats solid food helped a lot though. One benefit is a heightened (or actually: not dulled) sense of taste. I'm currently on a "cheat week" and it's already getting annoying that food doesn't taste as good. Dietitians say this again and again: even the best diet is no good if you can't keep to it.
- lm28469 4y ago
  > The latter usually comes after extended exercise If you're in shape and get enough sleep a moderate amount of exercise shouldn't make you tired. Being a parent might contribute more to the tiredness though
zvmaz 4y ago
That's completely counter-intuitive to me. My weight and appetite significantly drop when I stop weightlifting.
- phantompeace 4y ago
  Could that be explained by a body wide change in metabolism when not lifting heavy weights?
irthomasthomas 4y ago
And yet the received wisdom of centuries says to exercise to work up an appetite.
catchclose8919 4y ago
Anecdata: exercise massively reduces my otherwise constant craving for processed sugars, deep fried and smoked or cured things, alcohol and smokes. I'm not less hungry, but I'm less hungry for nasty stuff, so from my perspective there seems to be a lot of truth in this! Context: I'm natively extremely lazy (phisically, not intellectually), I find any phisical activity a pain an a nuisance, I derive zero pleasure from any kind of sport and phyisical exercise (except hiking and skidiving, but not the phisical effort aspects of them), the release-endorphines-on-effort circuit is 100% broken for me or I just lack the receptors for those endophins... eg. 100%-lazy-cat except not fat because genetically I come from a line of people slim-no-matter-what-we-eat. (Probably more average or atletic people's bodies just don't work like mine...)
- feet 4y ago
  My guess would be that's related to endorphins. They help feel satisfied, happy, content, and more positive mood in general
- pdimitar 4y ago
  Yeah I found the same. After I did the exercise grind for a bit of time I suddenly found out that my cravings for usual unhealthy foods have been reduced. My trainer and doctor say that we have various receptors in our bodies tuned for our current way of life and that diet and exercise re-program these receptors which, yeah, is what I observed as well. RE: your lack of motivation for working out, I found it is related to the type of exercise. The start of my journey was a series of train wrecks. I constantly stumbled on 22-year old boys whose wisdom was "get on the bench press, bro!" which didn't work for me. It was almost harmful even. After going to physiotherapy for a while I then started training under the tutelage of the same people and I am already better. They are very careful not to over-strain me, give me just enough cardio to keep my heart pumping but not to make me wanna die, exercises are carefully tuned to strain me a bit but never too much. They don't give me big pauses between exercises (60 - 90 seconds) however. Some exercises are mostly stretching and "activating" a certain muscle (meaning just exercising it a little without any strain). Not sure I can translate that to a workout strategy for you but these items might help: - Do 3 series of each exercise. If it's too much then 2; - Do more reps per series; - Rest until your heart calms down slightly but not beyond that; - Introduce a hard cap on the workout session -- mine is 1 hour. This was a huge struggle because I wanted to do all the exercises but there's no way to fit all in 1 hour (did that mistake several times); - Start with slight cardio -- 5 or 10 minutes. Don't make it the focus of the session, it's just to start you off (a mistake I made many times); - The moment you start feeling a tormenting strain is the moment where you train for 2-3 more minutes and cut the session short; - If that moment doesn't come, still stop at your time cap. The main point is to feel energetic and rejuvenated after the workout. Not "OMFG I wanna die!". My trainer / physiotherapist / masseur told me this is an extremely common problem for men because a lot of them just hang out in the gym and their main motivation is show-off and competition with others. He says there's a million ways to make yourself feel better by exercising and honestly? I believe him because it is happening to me. Finally, it's the most normal thing in the world to fine-tune the exercise session to your specifics and you shouldn't try and imitate other workout regimes if they don't work well for you. My trainer quickly found out I have strong arms, shoulders and upper back and is rarely giving me exercises for them -- just for maintaining them a bit. But my legs, abs and lower back are weaker so 80% of my exercises focus on that. Works great. If you are willing to press on, I wish you good luck. I am exactly like you, I view physical maintenance as nuisance and it's not easy to change the mindset. But I already started having that little little voice in my head that's sometimes nudging me to do a session because I know it makes me feel a bit better after. In programming terms, I'd say reduce the size of the program/tests until it's manageable for you. My trainer said it's much better to train every day for just 35-40 minutes compared to two workouts of our and half a week.
MrPatan 4y ago
I've observed something like this on myself. I eat less, and better, when I exercise. I don't know if you can outrun a bad diet, but maybe you can lift it.
belter 4y ago
Not paying 32 bucks for the study, but it seems the study was mostly done on mice. We share 99% percent of genes with mice but hope the 1% are important enough :-) The abstract mentions the effect also occurs on humans and horses, without further details if they were part of the study, or if is just well known. It could be a temporary effect. If you are trying to lose weight, change diet before starting with exercise. When at the proper weight, use exercise to keep at the correct level. Several studies compared two groups. One group changed just diet, and other used diet and exercise from the beginning. Faster weight loss noticed in the group just doing a diet change and not doing increased exercise. The assumption that the increase of exercise, might call for additional cravings, even if of a different type of food. [1] "...For weight loss, diet seems to be more effective than physical activity,"... "You have to do huge amounts of physical activity to lose weight, but you can get a better energy deficit just by cutting down on calories..." ... "...So both diet and physical activity are important,"..."Diet probably more important for losing weight. Physical activity for keeping it off..." [2] "...Despite the prevailing advice, exercise is pretty unhelpful for weight loss..." [1] "Mayo Clinic Minute: Which is better for losing weight – diet or exercise?": https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-minute-which-is-better-for-losing-weight-diet-or-exercise/ https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-mi... [2] "Why you shouldn't exercise to lose weight, explained with 60+ studies": https://www.vox.com/2016/4/28/11518804/weight-loss-exercise-myth-burn-calories https://www.vox.com/2016/4/28/11518804/weight-loss-exercise-...
- oriolid 4y ago
  The whole point is that people who do not have a fixed diet would spontaneously eat less after exercise because they do not feel hungry. This by the way matches my personal experience and there are several other comments saying the same thing.
- kybernetyk 4y ago
  >Faster weight loss noticed in the group just doing a diet change and not doing increased exercise. Did they track muscle mass? Because from personal anecdata: When I change diet and don't excercise I tend to lose "weight" faster (as weight on a scale) but a lot of that weight loss is from muscle mass. Just dieting makes me "skinny fat". When I exercise (resistance training like weight lifting - cardio is uslesess) I tend to lose weight on the scale slower but I look better and my muscle mass increases. I also feel _way_ better than on a restrictive diet.
BrianOnHN 4y ago
Anecdata: for the past decade, my preferred way to begin a ketosis regimine has been a long run to "burn off remaining blood sugar" based on the old-wisdom of "the body starts to utilize fat after 30min of intense exercise." This seems to work great. Fewer cravings. I've even taken a this a step further. Running on the first morning of a 3-day fast. Works the same. Note: I wouldn't recommend doing the above without carefully managing electrolytes. But, anyone who's been keto successfully for more than a month should understand what I mean about managing electrolytes.
- pjmorris 4y ago
  Could you point to a link or such regarding 'managing electrolytes?' I took my desk-bound self on a four day Appalachian Trail hike with friends recently and burned out hard at the end of the second day (~2600 ft elevation gain, sunny, hot) and am pretty sure dehydration was at the core. Some fellow hikers bailed me out with extra water spiked with Propel (~Gatorade), and I was fine the next day, but I'd like to be equipped with both supplies and understanding the next time I try something like that.
  - ddorian43 4y ago
    So you weren't eating on the trail? When you stop eating carbs, body uses carbs, carbs contain water, body removes water (think 4kg of water), the water removes electrolytes, you get "sick". A spoon of table salt in water fixed it once for me.
  - mcculley 4y ago
    I normally eat only once per day and occasionally go 2-3 days without food. I use these electrolytes: https://www.hammernutrition.com/endurolytes-fizz https://www.hammernutrition.com/endurolytes-fizz I notice a big difference in energy as long as I am drinking plenty of water and 1-2 of these per day, especially after a run.
  - nradov 4y ago
    Electrolytes is mainly sodium, plus a little magnesium and potassium. Dehydration can be an issue, but drinking more plain water won't replace sodium lost in sweat. You can buy electrolyte powders to mix in your water. Or just eat some salty food occasionally. https://drinklmnt.com/pages/ingredients https://drinklmnt.com/pages/ingredients Bonking hard on a moderate intensity activity can be a symptom of a messed up metabolism which can't produce enough energy from stored fat. If you want to check for sure you can visit a sports medicine lab for a metabolic profile test where they measure how much fat versus carbohydrates you burn at various effort levels. The usual recommendation to shift your metabolism to be more fat adapted is to do a lot more long Zone 2 (below ventilatory threshold) workouts but it can take years to see major changes. Sports drinks can be helpful to keep you going when you're struggling, but they tend to contain a lot of sugar and aren't ideal for daily consumption.
mark_l_watson 4y ago
I think this must be common knowledge. If I go on a long hike, I am not really hungry for a couple of hours afterwards. Often people I hike with want to immediately after the hike get food. I used to often skip going to a restaurant because I was not hungry, then decided as a practice to go anyway to be more “social.”
- Vinnl 4y ago
  Why would it be common knowledge, if many people you hike with have food cravings immediately after a hike?
  - mark_l_watson 4y ago
    The people I hike with like to go to a restaurant after hiking as another social event. I have talked with a few people who experience a lack of hunger after a lot of exercise, but maybe it is not common knowledge. A few other commenters here mentioned the same effect.
formerkrogemp 4y ago
Mass produce this. Feed to everyone. Global hunger solved?
sto_hristo 4y ago
That is so ironic.
johnnyApplePRNG 4y ago
I wonder if it's whatever gives you that runner's high... Stimulants of all kinds suppress appetite.
- FollowingTheDao 4y ago
  It's not. It is probably the thing that gets rid of the runners high actually. Since "Phenylalanine is a precursor for tyrosine, the monoamine neurotransmitters dopamine, norepinephrine (noradrenaline), epinephrine (adrenaline), and the skin pigment melanin..." combining it with lactate destroys this adrenaline high.
decebalus1 4y ago
Sample size of one, but I always lift weights fasted (12-16 hours fast) and I'm ready to eat a horse about an hour or two after my workout. I once ate a whole rotisserie chicken. I also crave burgers right after strenuous hikes or long bike rides. Perhaps I'm just badly configured.
pier25 4y ago
So now they only need to synthesize it and put it in a pill!
- FollowingTheDao 4y ago
  No need, there is already a pill that helps make lac-phe, it is called manganese, See my other comment.
FollowingTheDao 4y ago
You know what this tells me? Manganese deficiency probably plays a role in metabolic disorders and trouble losing weight with exercise. CNDP2, the enzyme that helps make lac-phe (N-[(S)-lactoyl]-L-phenylalanine) needs manganese as a cofactor. https://www.uniprot.org/uniprot/Q96KP4 https://www.uniprot.org/uniprot/Q96KP4 If you are deficient in Manganese, or need more Manganese because genetics, they you will not make as much lac-phe after working out. And indeed they find that manganese deficiency is related to metabolic disorders. https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/dietary-intake-of-manganese-and-the-risk-of-the-metabolic-syndrome-in-a-chinese-population/009A206B62A8B28FFF342FCF776F50B5 https://www.cambridge.org/core/journals/british-journal-of-n... https://academic.oup.com/jn/article-abstract/115/7/919/4755969?redirectedFrom=fulltext&login=false https://academic.oup.com/jn/article-abstract/115/7/919/47559...
ravenstine 4y ago
Although this is my guess based on experience, I think said anti-hunger effect can be had without intense exercise. I've noticed consistently that walking has an anti-hunger effect. Walking does take more time than running, but it doesn't really register as stress to the body in the same way that running and other forms of cardio do, meaning a lower cortisol response. Maybe it's not as strong an effect as with something like running, but I think it's worth observing and considering. In weighing the pros and cons, I think that walking is better in terms of longevity. Cortisol and stress on joints are things you don't really want.
- uwuemu 4y ago
- sumy23 4y ago
  I think research has shown the opposite. Low-intensity cardio makes people more hungry, in general. Personally, after a long hike, I have a voracious appetite.
  - ravenstine 4y ago
    Like I said, it's just a guess from my experience. It's a complicated subject because people can get "hungry" for different reasons. For me it could very well be that simply getting up to walk a 4-mile circuit around the neighborhood gives me enough of a goal and enjoyment that I feel less of a need to reach for food as entertainment, including the time following the walk. What gives me an appetite is weight lifting. I honestly don't get how people can't be hungry after lifting heavy. Could be psychological for me because I am also intent on building muscle, but still. My hunger after lifting is more visceral than my usual "gotta eat" feeling.
    - rmbyrro 4y ago
      > It's a complicated subject because people can get "hungry" for different reasons. When it comes to human health, every subject is like that. This is why we rely on randomized control groups, peer-review, and other mechanisms to reduce the chances of making wrong assumptions.
beardedman 4y ago
Ties up pretty well with my own experience. Eating after exercise always feels like a chore.
FpUser 4y ago
I've "discovered" it long time ago. Basically if I feel hungry but do some activity instead of eating the hunger disappears. Does not work on long cardio activity though. Anything longer than 2-3 hours (assuming it is not a leisure walk) exhausts my reserves and makes me hungry for real.
chobytes 4y ago
Yeah I believe it. I cycle like 100 miles a week on an entry level road/gravel bike... And Id say my hunger oscillates between large extremes from it. I definitely crave horrible sugary food and salt from doing like a 3h ride... but between rides when Im recovered I often wont even want a snack or anything if offered.
sdo72 4y ago
This is what I do all the time when controlling my weight, going through long fasting periods. I know for the fact that when being active even with 10-15 mins jog, I'm more insulin sensitive and it staves off my hunger immediately.
linspace 4y ago
My case is more biomechanical. Running will decrease hunger much more than cycling or the gym as it gives the stomach much less rest.
flobosg 4y ago
> It has also been reported that as an additive N-L-lactoyl phenylalanine improves the taste of food, conferring an umami flavor. It is found naturally in significant amounts in some traditional Chinese fermented foods such as preserved pickles and soy sauce. ―https://en.wikipedia.org/wiki/Lac-Phe https://en.wikipedia.org/wiki/Lac-Phe
ge96 4y ago
Personal anecdote regarding weight loss/fitness In 2 months I dropped 30 lbs, how was by fasting. I would only eat 1 big meal a day, as in drink coffee in the morning, not have a snack (fiber bar) until after 5PM (assuming 9-5 schedule) and then eat around 9PM/few hours before sleep. (means 1200-1500 calories per day vs. 2400+). The figure to keep in mind is a lb of fat is 3500c. Counting calories matters. The hard thing is sticking to it (obviously) as I rebounded and I gained that weight back already. I sit at a desk/don't really go outside much. You will feel a hunger pang and you will want to eat, but it will pass. I used to work next to a gym so it was easy to work out, I would just go to the gym after work, at times I would even work out as long as 4 hrs in a row. I was super cut back then, lifting. But the gym is now 5+ miles away from me one way and I used to go there 4-5 days a week. I could drive that but nah... 20 minutes of driving and 1-2 hrs at the gym that's a lot of lost time. Plus I used to go late at night/early morning so I had the entire gym to myself, I didn't have to wait for the squat area or bench, etc... I'm not doing that anymore, and I'm not really interested in getting body-building sculpted, just toned/visible muscle/low body fat. So I'm doing that at home, got some bands/one of those multi-use pull up bars... but diet is the main thing... if you have low body fat you will look better than with a lot... as in good chin definition, no gut... I have this personal denial going on where I wear baggy clothes/saying "I'm not THAT overweight" but I am by about 40lbs. Film yourself externally to see. I guess this really only matters if you care about external appearance/say trying to attract someone else, gotta meet them/be on their level. I am in my later 20's, 6ft weight should be around 210 but I'm at low 260s as of this moment. Was high 230, low 240s in Feb. My problem is I binge eat when I'm bored/watch TV. Last thing I'll mention, I also include some back stretching/exercise, light to keep the back strong since I sit on a stool all day (office chair but back broke off).
- chaorace 4y ago
  I concur. People are generally very hesitant to recommend fasting, because it is dangerous, but I'd argue that it's dangerous in the same sense as a very intense workout: not inherently damaging, but *certainly* capable of complicating pre-existing conditions. (NOT A DOCTOR, DO NOT SUE) Indeed, there is some science which suggests that fasting plays an important role in long-term homeostasis -- particularly when it comes to managing cellular senescence and insulin resistance[1]. I'm only a layperson, but I feel like there's a pretty clear parallel that can be drawn between exercise and fasting here; Human body metabolism developed in an environment where both of these processes would reliably play out over time, so it seems to follow that each would contribute important functions to the overall metabolic process. [1]: https://sci-hub.se/10.1056/NEJMra1905136 https://sci-hub.se/10.1056/NEJMra1905136
chriscappuccio 4y ago
The peptide is N-lactoylphenylalanine So a lot of folks on here are talking about the effects of exercise and stuff like endorphins. Andrew Huberman sums it up best 1. Dopamine and testosterone are closely linked 2. Effort releases dopamine and testosterone 3. Don't spike dopamine before or after effort, let effort spike dopamine 4. Testosterone makes effort feel good (Testosterone makes you feel good) 5. Winning increases testosterone, in all venues 6. Losing decreases testosterone, in all venues

289 points by echen 4y ago

Also anecdata. Whenever I'm exercising I know that I won't be hungry afterwards even if I was before. I always thought it was strange.

ianbutler 4y ago

With cardio I’m more hungry later in the day but weight lifting, not only do I get a better workout I have less cravings for junk and my hunger is way less.

arcticbull 4y ago

And yet folks who exercise also end up having acute compensatory eating. [1] Your body is designed to maintain homeostasis. Exercise is not how you lose weight, changing your diet up to and including fasting is. Exercise is good for you in a whole lot of other ways, but the idea you can outrun a bad diet is pretty thoroughly debunked at this point. [1] https://pubmed.ncbi.nlm.nih.gov/19419671/ https://pubmed.ncbi.nlm.nih.gov/19419671/

hardwaresofton 4y ago
Agreed on all points, but just want to point out that it would be ideal if you could supplement dieting with effective hunger suppression though —- their work towards isolating lactate and phenylalanine as signals towards hunger suppression is pretty impressive if it can give a foothold in that area.
benreesman 4y ago
You sound knowledgeable about this: I personally find that even when I’m having trouble controlling caloric intake as well as I’d like that sharp reductions in simple carbohydrates and sugars seem to help with weight loss even if my envelope math seems to indicate comparable total calories? Is this just bad measurement or is there anything to that?
- make3 4y ago
  research show that people are apparently terrible at evaluating how many calories they take, even dieticians. by cutting more addictive food, it's possible that you're actually eating less than your otherwise would, even if the numbers don't seem to add up
- bavell 4y ago
  Sounds to me like it's due to the ease of digesting simple carbs vs complex carbs, which require more digestion to process. I think with complex carbs your net calories gained are actually lower than what the nutrition label says since they require some amount of calories to digest.
elwesties 4y ago
It’s funny, they way I describe the relationship I have with weight loss is exercise is that the exercise is giving you the reason to eat clean. You won’t want to make that effort worth nothing. It’s not the same for everyone but I certainly notice it
- cehrlich 4y ago
  This is my experience as well. Going on a long run if you ate garbage the day before feels terrible, so you get conditioned to eat clean.
- Der_Einzige 4y ago
  Hahaha what? Sorry, but the term dirty bulking, and the existence of "eat big to get big" videos among the body builder community shows that many in the high end to elite strata of weight training not only just don't eat clean, but they also get their enjoyment and muscle from the absolutely nasty food they eat as part of it (... Yes and roids) https://youtu.be/PX33LjIMQoA https://youtu.be/PX33LjIMQoA
dhedberg 4y ago
For me personally I have noticed that exercising helps me by modulating my food cravings. I'll get hungry of course, but in a way where I'm more happy just eating some reasonable amount of actual food instead of stuffing myself with a bag of crisps or worse. This might also be psychological; it feels good after exercising so I feel more inclined to stay on the path. The result, either way, is that while I know from experience that just changing my diet works to lose weight, it becomes a lot easier to keep it up when also exercising.
paskozdilar 4y ago
> Exercise is good for you in a whole lot of other ways, but the idea you can outrun a bad diet is pretty thoroughly debunked at this point. Perhaps you can't "outrun" a bad diet, but you can certainly out-lift it. Weight training leads to stronger muscles, stronger muscles spend more energy, more energy spent leads to losing weight.
- arcticbull 4y ago
  This is another one of those fun little half-truths. > 10 pounds of muscle would burn 50 calories in a day spent at rest, while 10 pounds of fat would burn 20 calories [1] 50 pounds of fat burns 100 calories per day. 10 pounds of muscle burns 50 calories per day. If you lose 50 pounds of fat and replace it with 10 pounds of muscle, you're net 50 calories per day. About 1/10th of a Starbucks muffin. Not eating a Starbucks muffin is the same as having 90 extra pounds of muscle. You'd have to look like John Cena for this to make any difference whatsoever. But you're never going to look like John Cena unless you adjust your diet. The only way to lose fat is to change your diet. [1] https://www.webmd.com/diet/obesity/features/8-ways-to-burn-calories-and-fight-fat https://www.webmd.com/diet/obesity/features/8-ways-to-burn-c...
  - paskozdilar 4y ago
    > at rest Who said anything about resting? I'm talking about exercise. The more you exercise, the more muscle you build, which makes you spend more energy while exercising. Do you have any idea how much bodybuilders eat, without gaining any significant fat? > The only way to lose fat is to change your diet. False. You can lose fat by exercising, without changing your diet whatsoever.
    - arcticbull 4y ago
      > Who said anything about resting? I'm talking about exercise. The more you exercise, the more muscle you build, which makes you spend more energy while exercising. Again muscle vs fat don't change significantly that quantity of calories burned, unless you have some citations. > False. You can lose fat by exercising, without changing your diet whatsoever. Not in any practical sense. Most folks don't have the time to run a five-miler for each muffin they eat in a given day. This advice is just not useful. It's technically correct but totally unhelpful. It's basically the tautology: 'once you've lost weight you've lost weight.'
glenngillen 4y ago
I’d heard this for years and was quite the skeptic. I’d hit the gym pretty consistently in my late teens and cycled a lot and kept a pretty consistent weight irrespective of what I ate. Over the better part of 20 years the only real fluctuations were during extended travel periods where both diet was bad and exercise non-existent. But multiple marathons, extended focus on weight training, picking up various sports again, and I’d oscillate in about a 3kg range. And then my wife had to go on an extended elimination diet to deal with gastrointestinal issues and I joined as moral support. In the space of a month, with absolutely no exercise happening, I dropped 10kgs. And I don’t think I’d ever felt healthier. As soon as I got back to running I was as quick as I’d ever been, no great surprise I guess given how much lighter I was. Turns out the biggest impact I could have on my health was being more conscious of what I was eating. I couldn’t out run what I was putting in my mouth, no matter the distances I was putting in.
- joshu 4y ago
  my trainer says “you can’t outrun a cheesburger.” i should probably stop showing up with mcdonalds
  - bennyelv 4y ago
    Anecdata warning - you actually can! The problem with trying to outrun a cheeseburger is that you probably need to be quite fit to do it. It works like this: If you're unfit, your capacity for output during exercise is less. If you're fitter, your capacity for output during exercise is higher. An unfit person doing exercise, will therefore burn significantly fewer calories than someone who is fit if they exercise for the same duration at the same perceived effort. If I go for a hard 1 hour bike ride, I burn 3 cheeseburgers. An unfit person will struggle to burn much more than 1 despite working as hard as they can.
    - count 4y ago
      This seems to run counter to what I see in data based on heart rate at least. As you get more fit, your cardio conditioning level goes up, which means you are substantially more efficient in exercise. When you're not efficient, you'll burn more calories doing the same work.
asdff 4y ago
People doubting the power of caloric deficit need to watch Alone. People scarcely bringing in one squirrels-worth of calories a day while laboring around camp are just sloughing off the weight on that show. Some have gotten pulled for medical because they were losing it too fast and stressing their heart. One guy lost 86 pounds in 67 days.
- xorfish 4y ago
  That is not a good rate to lose weight. A rate of ~1% per week for 3-4 months followed by 1-2 months of maintenance before the next weight loss phase is much more sustainable and you are more likely to not gain back the weight after the target weight is achieved.
  - asdff 4y ago
    Yeah its a terrible way to lose weight, that's why stickies on places like bodybuilding forums encourage a moderate deficit plus exercise to maintain bone and organ health (1). But it goes to show that with a deficit you will shed weight. There is no special sauce in individual metabolism that makes energy from nothing at the end of the day. Losing weight is a matter of thermodynamics. 1. https://forum.bodybuilding.com/showthread.php?t=165843261 https://forum.bodybuilding.com/showthread.php?t=165843261
  - arcticbull 4y ago
    This seems to be folk wisdom, but is it supported by any actual data?
thesz 4y ago
As I said elsewhere here, it is not the case for me - I quite often experience food aversion after exercise (weight training). I exercise in fasted state, 14-18 hours of fast. If exercise is especially hard, I found food not attractive at all, neither how it looks or how it smells. I have to force myself to eat when this happen and usually eat less. On bright side, I've found that I recover faster after exercise bouts when I'm in fasted state. I also have to note that was not the case when I was younger and performed my training routines after being fed. When I exercised being fed I experienced hunger and wanted to eat.

veltas 4y ago

I always get a monster appetite after exercise, could just be conditioning. Sample size of one.

thesz 4y ago
For several years I exercise in fasting state, 14-18 hours of fasting. I can easily not eat for three hours after exercise. Actually, I experience no hunger at all. Could just be conditioning. Sample size of one.
- ID1452319 4y ago
  What sort of exercise were you doing fasted? Did you find it impacted your performance?
  - thesz 4y ago
    Weight resistance training, mostly. Also occasional Tabata squats for some endurance. I found that I recover from quite intensive sets faster when training fasted. The decline in performance I experience can be explained by my age and, frankly, that I do not exercise regularly enough.
- foolfoolz 4y ago
  i think 90% of huger is conditioning. you can train yourself to eat less. you can train yourself to stop being hungry. and it doesn’t take long, maybe a month or so
asdff 4y ago
Especially cardio I will actually get faint if I don't keep up with food. On long bike rides I will eat two al pastor tacos every 20 miles from a stand or truck. A lot of those 10/25/50/100 mile charity bike rides have regular stops with peanut butter packets or beer too so riders can get liquid calories and carbs (and a buzz of course).
idoubtit 4y ago
After a few hours of intense activity, I'm usually very hungry. But when I walk in the mountains for full days (8-12 hours per day), I don't have much of an appetite, especially after two days. I almost have to force myself to eat a real lunch and dinner, though I tend to frequently eat small quantities of dried fruits.

psiops 4y ago

This would explain why exercise causes weight loss even though people with sedentary and active lifestyles seem to burn the same amount of calories[1] [1] https://dupri.duke.edu/news-events/news/herman-pontzer-explains-where-our-calories-really-go-and-what-studying-humanitys https://dupri.duke.edu/news-events/news/herman-pontzer-expla...

benreesman 4y ago

If this is just me whinging then I apologize, but in my own life and among some people I know: the insane bifurcation into monster fitness where it’s more important than your job and “no one cares” seems to be a driver of careless weight management. The standard of being “in shape” has gotten so absurd, and the nonlinear payoff around fitness so steep at the “maybe doing some pretty extreme shit” cutoff that I’m personally surprised I have t just given up, and it seems a lot of people have. I don’t know if it’s TikTok, or Marvel movies, or whatever: but “fucking mutant superhero” used to one among many attractive archetypes.

FeaturelessBug 4y ago
I don't know if my own anecdote will help you but I've been overweight since I was a child and I've done just about every diet under the moon. I used to hate myself and my body, a lot. I went to the gym three days a days week pushing myself hard and counted calories, and my weight wouldn't budge. I ended up developing a lot of disordered eating doing fasting and I really thought I could hate myself into being thin. When I finally found keto and it worked, I started dropping weight and I quickly lost control of my diet and started to starve myself in earnest while continuing what exercise I could. After a while all I could do was take long walks. I lost 80 pounds in 8 months doing this, and I was still considered over weight by about 60 pounds. I never got any happier with myself by changing my body. I still didn't think I was worth anything unless I could get tiny. I had really bad brain fog, I stopped being able to produce my own body heat, started to have fainting spells, and finally heart palpitations. When I went to the doctor all they told me is what a good job I was doing losing weight and that the palpitations were from my panic disorder. I finally stopped keto because my partner sat me down and begged me to stop. It was really hard and it took time to give it up, but I finally did. I had no real muscle left and I was so fatigued... Over the course of a year... I gained all the weight back. I still have palpitations sometimes, and I will never know what damage yoyo dieting for years did to me. I don't diet anymore, I've started intuitive eating and my diet has improved over all. I eat variety now, more vegetables and lots of protein. I also have carbs, and dessert with I want it. I've also started doing things for the experience rather than to make my body look a certain and ultimately unattainable way. I don't focus on how I look anymore, I focus on being strong. I am now highly active and doing activities I never thought I would be capable of in my fat body. I take dance classes four times a week, I lift weights, and I am starting Lyra and aerial classes. I also don't step on scales anymore. But I can tell you I haven't magically shrunk. I guess what I'm trying to say is... Any standard of "in shape" can be impossible for any person. We aren't all meant to look that same and I think that people are caring less about being overweight because it should never have been a limiting factor to you enjoying your life, being active, and being well loved by the right people.

DoreenMichele 4y ago

“We estimate that the lac-phe pathway is responsible for about 25% of the anti-obesity effects of exercise,” Long said. I find this article annoying. It should come as no surprise that there is a mechanism for suppressing appetite during physical activity. There is only so much blood to go around and both digestion and exercise place demands on the blood supply. It would be a hardship to place both demands on the body at the same time consistently.

have_faith 4y ago
> I find this article annoying. Why is it annoying? confirming unsurprising results is important.
- DoreenMichele 4y ago
  Because it's framed like research for a potential weight loss pill rather than research into the mechanism behind the fairly well-known fact that people typically have less appetite while being physically active. I hate the tendency to frame everything in terms of a pill to fix our problems and/or a get rich quick scheme as a substitute for trying to figure out how to live right.
  - vosper 4y ago
    You’re absolutely right about the quality of the submitted article. It’s written like low-grade clickbait tech “journalism”. It’s even worse than the battery-breakthrough-of-the-week university PR pieces that get posted here. I imagine the research is good and useful. Pity about the way it’s been presented.
  - FollowingTheDao 4y ago
    It is actually more important than you thing since it links manganese to metabolic syndrome.

freiherr 4y ago

>Does this finding hold promise for that ever-elusive diet pill? I wonder what will go wrong this time with side-effects. Maybe overeating rebound after it gets out of the system. That would resemble natural compensation of calories after activity is finished. From personal experience I recommend saturated fat (mostly from beef tallow) as an anti-hunger molecule. With as little as possible omega-6 in the diet. And carnivore. Works wonders. My satiety base level is now set so that I get down to ~12% bf in a reasonable time when I'm above that. Could also bulk up to a powerlifting competition on this diet no problem when necessary.

ddorian43 4y ago
Yes, just tried bulking on a 6 week program and was very impressed with carnivore.
- a3w 4y ago
  Meat very slightly causes cancer. Saturated fats reduce your life expectancy, too. Not that good advice I guess?
  - blfr 4y ago
    Check the studies you're relying on for this information. Most are confounded by people simply eating fast food.
    - quickthrower2 4y ago
      And fast food is different because… ?
      - blfr 4y ago
        Lots of crappy carbs and added sugar on the side with generally low quality ingredients compared to what anyone caring about their diet would eat. Most people don't have the dedication of a body builder carefully eating only patties from the burgers. Which would probably work.

nonrandomstring 4y ago

The article mentions that a substance (lactose-phenylalanine) appears after exercise in several animal studies. There's a suggestion of a strong connection of this to reduced appetite. But this isn't explained and more importantly there's no hypothesised mechanism. Why would it be a metabolic advantage to reduce hunger after exertion? Maybe it creates a buffer-period. Otherwise, common sense/intuition would say we feel hungrier after exercise. What gives?

aqme28 4y ago
My guess is that exercise implies that you're doing something important (fighting, fleeing, etc), and it is not the time to be distracted by hunger.
otikik 4y ago
“After” is what happens now, when we are in control of our time “I will hit the gym for one hour”. In our past, physical activity was a survival-related task with no fixed end time (chasing a prey, fleeing from danger). I think for our ancestors it would happen during exertion. It would not be advantageous to feel increasingly hungry while exercising, the same way that it makes sense for adrenaline to block pain during a fight. Less distraction, more survival
- hinkley 4y ago
  I think it helps if you think of exercise as what it is: lying. A longshoreman is strong because he spends all day shifting cargo around. Steve is big and buff because he tricks his body into thinking shifting cargo around all day is a likely scenario. Muscle is expensive. The body is very stingy with keeping muscle you don't need on a regular basis. A gym visit is trying to simulate the behavior of all-day exertion without having to abandon all of the other activities you want to fill your day with.
fasteo 4y ago
>>> Otherwise, common sense/intuition would say we feel hungrier after exercise. What gives? I would hypothesize that recovery and digestion are two metabolically intensive activities that the body is unable to do them simultaneously, so it would make sense to suppress hunger while the body recovers itself from exercise. Now, the supplement industry has made us believe that if you don't consume food within the magical anabolic window, you recovery will be impaired. Nonsense if you ask me.

10x-dev 4y ago

Anecdata: when I was intermittently fasting, I found that exercising at lunch curbed my appetite and I could easily last till dinner with no food or with a small yogurt snack (<50cal). On days when I didn't exercise, I felt hungrier and had to engage my will power much more during the day.

Tade0 4y ago

Now that I am a parent I often eat work for breakfast. I've found that two things cause massive hunger in my case: a diet rich in added sugar/salt and being tired. The latter usually comes after extended exercise, so appears to be counterproductive for weight loss. Other benefits still apply though. Just dropping added sugar/salt now that my child eats solid food helped a lot though. One benefit is a heightened (or actually: not dulled) sense of taste. I'm currently on a "cheat week" and it's already getting annoying that food doesn't taste as good. Dietitians say this again and again: even the best diet is no good if you can't keep to it.

lm28469 4y ago
> The latter usually comes after extended exercise If you're in shape and get enough sleep a moderate amount of exercise shouldn't make you tired. Being a parent might contribute more to the tiredness though

zvmaz 4y ago

That's completely counter-intuitive to me. My weight and appetite significantly drop when I stop weightlifting.

phantompeace 4y ago
Could that be explained by a body wide change in metabolism when not lifting heavy weights?

irthomasthomas 4y ago

And yet the received wisdom of centuries says to exercise to work up an appetite.

catchclose8919 4y ago

Anecdata: exercise massively reduces my otherwise constant craving for processed sugars, deep fried and smoked or cured things, alcohol and smokes. I'm not less hungry, but I'm less hungry for nasty stuff, so from my perspective there seems to be a lot of truth in this! Context: I'm natively extremely lazy (phisically, not intellectually), I find any phisical activity a pain an a nuisance, I derive zero pleasure from any kind of sport and phyisical exercise (except hiking and skidiving, but not the phisical effort aspects of them), the release-endorphines-on-effort circuit is 100% broken for me or I just lack the receptors for those endophins... eg. 100%-lazy-cat except not fat because genetically I come from a line of people slim-no-matter-what-we-eat. (Probably more average or atletic people's bodies just don't work like mine...)

feet 4y ago
My guess would be that's related to endorphins. They help feel satisfied, happy, content, and more positive mood in general
pdimitar 4y ago
Yeah I found the same. After I did the exercise grind for a bit of time I suddenly found out that my cravings for usual unhealthy foods have been reduced. My trainer and doctor say that we have various receptors in our bodies tuned for our current way of life and that diet and exercise re-program these receptors which, yeah, is what I observed as well. RE: your lack of motivation for working out, I found it is related to the type of exercise. The start of my journey was a series of train wrecks. I constantly stumbled on 22-year old boys whose wisdom was "get on the bench press, bro!" which didn't work for me. It was almost harmful even. After going to physiotherapy for a while I then started training under the tutelage of the same people and I am already better. They are very careful not to over-strain me, give me just enough cardio to keep my heart pumping but not to make me wanna die, exercises are carefully tuned to strain me a bit but never too much. They don't give me big pauses between exercises (60 - 90 seconds) however. Some exercises are mostly stretching and "activating" a certain muscle (meaning just exercising it a little without any strain). Not sure I can translate that to a workout strategy for you but these items might help: - Do 3 series of each exercise. If it's too much then 2; - Do more reps per series; - Rest until your heart calms down slightly but not beyond that; - Introduce a hard cap on the workout session -- mine is 1 hour. This was a huge struggle because I wanted to do all the exercises but there's no way to fit all in 1 hour (did that mistake several times); - Start with slight cardio -- 5 or 10 minutes. Don't make it the focus of the session, it's just to start you off (a mistake I made many times); - The moment you start feeling a tormenting strain is the moment where you train for 2-3 more minutes and cut the session short; - If that moment doesn't come, still stop at your time cap. The main point is to feel energetic and rejuvenated after the workout. Not "OMFG I wanna die!". My trainer / physiotherapist / masseur told me this is an extremely common problem for men because a lot of them just hang out in the gym and their main motivation is show-off and competition with others. He says there's a million ways to make yourself feel better by exercising and honestly? I believe him because it is happening to me. Finally, it's the most normal thing in the world to fine-tune the exercise session to your specifics and you shouldn't try and imitate other workout regimes if they don't work well for you. My trainer quickly found out I have strong arms, shoulders and upper back and is rarely giving me exercises for them -- just for maintaining them a bit. But my legs, abs and lower back are weaker so 80% of my exercises focus on that. Works great. If you are willing to press on, I wish you good luck. I am exactly like you, I view physical maintenance as nuisance and it's not easy to change the mindset. But I already started having that little little voice in my head that's sometimes nudging me to do a session because I know it makes me feel a bit better after. In programming terms, I'd say reduce the size of the program/tests until it's manageable for you. My trainer said it's much better to train every day for just 35-40 minutes compared to two workouts of our and half a week.

MrPatan 4y ago

I've observed something like this on myself. I eat less, and better, when I exercise. I don't know if you can outrun a bad diet, but maybe you can lift it.

belter 4y ago

Not paying 32 bucks for the study, but it seems the study was mostly done on mice. We share 99% percent of genes with mice but hope the 1% are important enough :-) The abstract mentions the effect also occurs on humans and horses, without further details if they were part of the study, or if is just well known. It could be a temporary effect. If you are trying to lose weight, change diet before starting with exercise. When at the proper weight, use exercise to keep at the correct level. Several studies compared two groups. One group changed just diet, and other used diet and exercise from the beginning. Faster weight loss noticed in the group just doing a diet change and not doing increased exercise. The assumption that the increase of exercise, might call for additional cravings, even if of a different type of food. [1] "...For weight loss, diet seems to be more effective than physical activity,"... "You have to do huge amounts of physical activity to lose weight, but you can get a better energy deficit just by cutting down on calories..." ... "...So both diet and physical activity are important,"..."Diet probably more important for losing weight. Physical activity for keeping it off..." [2] "...Despite the prevailing advice, exercise is pretty unhelpful for weight loss..." [1] "Mayo Clinic Minute: Which is better for losing weight – diet or exercise?": https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-minute-which-is-better-for-losing-weight-diet-or-exercise/ https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-mi... [2] "Why you shouldn't exercise to lose weight, explained with 60+ studies": https://www.vox.com/2016/4/28/11518804/weight-loss-exercise-myth-burn-calories https://www.vox.com/2016/4/28/11518804/weight-loss-exercise-...

oriolid 4y ago
The whole point is that people who do not have a fixed diet would spontaneously eat less after exercise because they do not feel hungry. This by the way matches my personal experience and there are several other comments saying the same thing.
kybernetyk 4y ago
>Faster weight loss noticed in the group just doing a diet change and not doing increased exercise. Did they track muscle mass? Because from personal anecdata: When I change diet and don't excercise I tend to lose "weight" faster (as weight on a scale) but a lot of that weight loss is from muscle mass. Just dieting makes me "skinny fat". When I exercise (resistance training like weight lifting - cardio is uslesess) I tend to lose weight on the scale slower but I look better and my muscle mass increases. I also feel _way_ better than on a restrictive diet.

BrianOnHN 4y ago

Anecdata: for the past decade, my preferred way to begin a ketosis regimine has been a long run to "burn off remaining blood sugar" based on the old-wisdom of "the body starts to utilize fat after 30min of intense exercise." This seems to work great. Fewer cravings. I've even taken a this a step further. Running on the first morning of a 3-day fast. Works the same. Note: I wouldn't recommend doing the above without carefully managing electrolytes. But, anyone who's been keto successfully for more than a month should understand what I mean about managing electrolytes.

pjmorris 4y ago
Could you point to a link or such regarding 'managing electrolytes?' I took my desk-bound self on a four day Appalachian Trail hike with friends recently and burned out hard at the end of the second day (~2600 ft elevation gain, sunny, hot) and am pretty sure dehydration was at the core. Some fellow hikers bailed me out with extra water spiked with Propel (~Gatorade), and I was fine the next day, but I'd like to be equipped with both supplies and understanding the next time I try something like that.
- ddorian43 4y ago
  So you weren't eating on the trail? When you stop eating carbs, body uses carbs, carbs contain water, body removes water (think 4kg of water), the water removes electrolytes, you get "sick". A spoon of table salt in water fixed it once for me.
- mcculley 4y ago
  I normally eat only once per day and occasionally go 2-3 days without food. I use these electrolytes: https://www.hammernutrition.com/endurolytes-fizz https://www.hammernutrition.com/endurolytes-fizz I notice a big difference in energy as long as I am drinking plenty of water and 1-2 of these per day, especially after a run.
- nradov 4y ago
  Electrolytes is mainly sodium, plus a little magnesium and potassium. Dehydration can be an issue, but drinking more plain water won't replace sodium lost in sweat. You can buy electrolyte powders to mix in your water. Or just eat some salty food occasionally. https://drinklmnt.com/pages/ingredients https://drinklmnt.com/pages/ingredients Bonking hard on a moderate intensity activity can be a symptom of a messed up metabolism which can't produce enough energy from stored fat. If you want to check for sure you can visit a sports medicine lab for a metabolic profile test where they measure how much fat versus carbohydrates you burn at various effort levels. The usual recommendation to shift your metabolism to be more fat adapted is to do a lot more long Zone 2 (below ventilatory threshold) workouts but it can take years to see major changes. Sports drinks can be helpful to keep you going when you're struggling, but they tend to contain a lot of sugar and aren't ideal for daily consumption.

mark_l_watson 4y ago

I think this must be common knowledge. If I go on a long hike, I am not really hungry for a couple of hours afterwards. Often people I hike with want to immediately after the hike get food. I used to often skip going to a restaurant because I was not hungry, then decided as a practice to go anyway to be more “social.”

Vinnl 4y ago
Why would it be common knowledge, if many people you hike with have food cravings immediately after a hike?
- mark_l_watson 4y ago
  The people I hike with like to go to a restaurant after hiking as another social event. I have talked with a few people who experience a lack of hunger after a lot of exercise, but maybe it is not common knowledge. A few other commenters here mentioned the same effect.

formerkrogemp 4y ago

Mass produce this. Feed to everyone. Global hunger solved?

sto_hristo 4y ago

That is so ironic.

johnnyApplePRNG 4y ago

I wonder if it's whatever gives you that runner's high... Stimulants of all kinds suppress appetite.

FollowingTheDao 4y ago
It's not. It is probably the thing that gets rid of the runners high actually. Since "Phenylalanine is a precursor for tyrosine, the monoamine neurotransmitters dopamine, norepinephrine (noradrenaline), epinephrine (adrenaline), and the skin pigment melanin..." combining it with lactate destroys this adrenaline high.

decebalus1 4y ago

Sample size of one, but I always lift weights fasted (12-16 hours fast) and I'm ready to eat a horse about an hour or two after my workout. I once ate a whole rotisserie chicken. I also crave burgers right after strenuous hikes or long bike rides. Perhaps I'm just badly configured.

pier25 4y ago

So now they only need to synthesize it and put it in a pill!

FollowingTheDao 4y ago
No need, there is already a pill that helps make lac-phe, it is called manganese, See my other comment.

FollowingTheDao 4y ago

You know what this tells me? Manganese deficiency probably plays a role in metabolic disorders and trouble losing weight with exercise. CNDP2, the enzyme that helps make lac-phe (N-[(S)-lactoyl]-L-phenylalanine) needs manganese as a cofactor. https://www.uniprot.org/uniprot/Q96KP4 https://www.uniprot.org/uniprot/Q96KP4 If you are deficient in Manganese, or need more Manganese because genetics, they you will not make as much lac-phe after working out. And indeed they find that manganese deficiency is related to metabolic disorders. https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/dietary-intake-of-manganese-and-the-risk-of-the-metabolic-syndrome-in-a-chinese-population/009A206B62A8B28FFF342FCF776F50B5 https://www.cambridge.org/core/journals/british-journal-of-n... https://academic.oup.com/jn/article-abstract/115/7/919/4755969?redirectedFrom=fulltext&login=false https://academic.oup.com/jn/article-abstract/115/7/919/47559...

ravenstine 4y ago

Although this is my guess based on experience, I think said anti-hunger effect can be had without intense exercise. I've noticed consistently that walking has an anti-hunger effect. Walking does take more time than running, but it doesn't really register as stress to the body in the same way that running and other forms of cardio do, meaning a lower cortisol response. Maybe it's not as strong an effect as with something like running, but I think it's worth observing and considering. In weighing the pros and cons, I think that walking is better in terms of longevity. Cortisol and stress on joints are things you don't really want.

uwuemu 4y ago
sumy23 4y ago
I think research has shown the opposite. Low-intensity cardio makes people more hungry, in general. Personally, after a long hike, I have a voracious appetite.
- ravenstine 4y ago
  Like I said, it's just a guess from my experience. It's a complicated subject because people can get "hungry" for different reasons. For me it could very well be that simply getting up to walk a 4-mile circuit around the neighborhood gives me enough of a goal and enjoyment that I feel less of a need to reach for food as entertainment, including the time following the walk. What gives me an appetite is weight lifting. I honestly don't get how people can't be hungry after lifting heavy. Could be psychological for me because I am also intent on building muscle, but still. My hunger after lifting is more visceral than my usual "gotta eat" feeling.
  - rmbyrro 4y ago
    > It's a complicated subject because people can get "hungry" for different reasons. When it comes to human health, every subject is like that. This is why we rely on randomized control groups, peer-review, and other mechanisms to reduce the chances of making wrong assumptions.

beardedman 4y ago

Ties up pretty well with my own experience. Eating after exercise always feels like a chore.

FpUser 4y ago

I've "discovered" it long time ago. Basically if I feel hungry but do some activity instead of eating the hunger disappears. Does not work on long cardio activity though. Anything longer than 2-3 hours (assuming it is not a leisure walk) exhausts my reserves and makes me hungry for real.

chobytes 4y ago

Yeah I believe it. I cycle like 100 miles a week on an entry level road/gravel bike... And Id say my hunger oscillates between large extremes from it. I definitely crave horrible sugary food and salt from doing like a 3h ride... but between rides when Im recovered I often wont even want a snack or anything if offered.

sdo72 4y ago

This is what I do all the time when controlling my weight, going through long fasting periods. I know for the fact that when being active even with 10-15 mins jog, I'm more insulin sensitive and it staves off my hunger immediately.

linspace 4y ago

My case is more biomechanical. Running will decrease hunger much more than cycling or the gym as it gives the stomach much less rest.

flobosg 4y ago

> It has also been reported that as an additive N-L-lactoyl phenylalanine improves the taste of food, conferring an umami flavor. It is found naturally in significant amounts in some traditional Chinese fermented foods such as preserved pickles and soy sauce. ―https://en.wikipedia.org/wiki/Lac-Phe https://en.wikipedia.org/wiki/Lac-Phe

ge96 4y ago

Personal anecdote regarding weight loss/fitness In 2 months I dropped 30 lbs, how was by fasting. I would only eat 1 big meal a day, as in drink coffee in the morning, not have a snack (fiber bar) until after 5PM (assuming 9-5 schedule) and then eat around 9PM/few hours before sleep. (means 1200-1500 calories per day vs. 2400+). The figure to keep in mind is a lb of fat is 3500c. Counting calories matters. The hard thing is sticking to it (obviously) as I rebounded and I gained that weight back already. I sit at a desk/don't really go outside much. You will feel a hunger pang and you will want to eat, but it will pass. I used to work next to a gym so it was easy to work out, I would just go to the gym after work, at times I would even work out as long as 4 hrs in a row. I was super cut back then, lifting. But the gym is now 5+ miles away from me one way and I used to go there 4-5 days a week. I could drive that but nah... 20 minutes of driving and 1-2 hrs at the gym that's a lot of lost time. Plus I used to go late at night/early morning so I had the entire gym to myself, I didn't have to wait for the squat area or bench, etc... I'm not doing that anymore, and I'm not really interested in getting body-building sculpted, just toned/visible muscle/low body fat. So I'm doing that at home, got some bands/one of those multi-use pull up bars... but diet is the main thing... if you have low body fat you will look better than with a lot... as in good chin definition, no gut... I have this personal denial going on where I wear baggy clothes/saying "I'm not THAT overweight" but I am by about 40lbs. Film yourself externally to see. I guess this really only matters if you care about external appearance/say trying to attract someone else, gotta meet them/be on their level. I am in my later 20's, 6ft weight should be around 210 but I'm at low 260s as of this moment. Was high 230, low 240s in Feb. My problem is I binge eat when I'm bored/watch TV. Last thing I'll mention, I also include some back stretching/exercise, light to keep the back strong since I sit on a stool all day (office chair but back broke off).

chaorace 4y ago
I concur. People are generally very hesitant to recommend fasting, because it is dangerous, but I'd argue that it's dangerous in the same sense as a very intense workout: not inherently damaging, but *certainly* capable of complicating pre-existing conditions. (NOT A DOCTOR, DO NOT SUE) Indeed, there is some science which suggests that fasting plays an important role in long-term homeostasis -- particularly when it comes to managing cellular senescence and insulin resistance[1]. I'm only a layperson, but I feel like there's a pretty clear parallel that can be drawn between exercise and fasting here; Human body metabolism developed in an environment where both of these processes would reliably play out over time, so it seems to follow that each would contribute important functions to the overall metabolic process. [1]: https://sci-hub.se/10.1056/NEJMra1905136 https://sci-hub.se/10.1056/NEJMra1905136

chriscappuccio 4y ago

The peptide is N-lactoylphenylalanine So a lot of folks on here are talking about the effects of exercise and stuff like endorphins. Andrew Huberman sums it up best 1. Dopamine and testosterone are closely linked 2. Effort releases dopamine and testosterone 3. Don't spike dopamine before or after effort, let effort spike dopamine 4. Testosterone makes effort feel good (Testosterone makes you feel good) 5. Winning increases testosterone, in all venues 6. Losing decreases testosterone, in all venues