9 ms·

Exercise elicits superior metabolic effects in the afternoon compared to morning [pdf]

55 points by prostoalex 6y ago

arrayjumper 6y ago
This study appears to be specifically about people with Type 2 Diabetes. I wonder if the same holds true for healthy adults.
- ac29 6y ago
  And it was only men, and it was a rather small sample size (32 total, split 12 morning and 20 afternoon).
biren34 6y ago
I understand the desire to investigate stuff like this, but for 90%+ of people, every inquiry in to "most optimal way to not be debilitating unhealthy" is just a waste of time. If you're not in a special group (gout, hypertension, allergies, etc.) the answer is incredibly simple: - your diet determines your size - your activities (or lack thereof) determine your shape I realize that type 2 diabetics (as being studied in this paper) might be considered one of those groups, but as far as I can tell, almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. Maybe that's just me, but I feel like we're searching for our keys under streetlight here. These are easily studied problems, so there are papers/book written. Trying to understand the myriad psychological and societal (and possible environmental) processes is where the real gains will be made.
- winstonchecksin 6y ago
  >your diet determines your size - your activities (or lack thereof) determine your shape Damn. This is really well stated. With all the hundreds of fitness experts and personalities on the Internet and YouTube, it actually just comes down to this.
  - klodolph 6y ago
    People also say "your body is made in the gym, but revealed in the kitchen". It's a bit of a simplification, but it requires so much exercise to burn the calories in a snack, it's easier to just not have the snack in the first place.
    - ImprovedSilence 6y ago
      similar, but we always used to say "abs are made in the kitchen, not in the gym".
    - codq 6y ago
      Yep. A blueberry muffin is around 424 calories. It takes about 45 minutes to burn that many calories jogging. Compare that to how many minutes it takes to simply not eat that muffin. A lot of people are afraid of the feeling of ‘hunger’; I find the sensation of hunger is actually a motivating one. I try to fast around 16 hours a day (eating window 12pm-8pm) and really think it keeps my head clear and helps me work, especially in the morning.
      - dvt 6y ago
        > I try to fast around 16 hours a day (eating window 12pm-8pm) I've been doing intermittent fasting for ~5 years now, and I don't even feel the hunger anymore. The only time I feel it is when I aggressively work out (running ~2 miles in the morning + lifting ~45 mins in the afternoon 5 days a week) and if I'm on a caloric deficit (~1750kcal). I also notice I get that hungry feeling particularly if my macros shift away from carbs (which they usually do when cutting weight). The human body is an incredible machine.
        xupybd 6y ago
        Have you tried upping your fat when you are cutting? I find that my hunger tends to be controlled mainly by my fat intake.
        6y ago
- DiabloD3 6y ago
  Remember, diet composition effects size, not some weird obsession with "calories in calories out" in some non-scientific cargo cult way.
  - kiba 6y ago
    Calories in, calories out absolutely work. Except that humans don't manage their diet by counting calories. We have regulatory mechanism that supposed to do the calories counting for us.
    - amanaplanacanal 6y ago
      Calories in calories out could help if you could accurately measure them. I suspect that most people can’t. But you are right, internal mechanisms regulate both hunger and activity levels.
      - kiba 6y ago
        The point is that we shouldn't need to count calories.
    - fighterpilot 6y ago
      > Calories in, calories out absolutely work. Is this really true and known empirically? Could the body be better at accessing calories in some foods and not others? Thought experiment: suppose I wrapped a small chocolate bar into airtight plastic, then I swallowed it. I have just swallowed 200 calories, but my body will access/process/burn 0% of it since it can't break down the plastic. At least in this one (unrealistic) example, CICO is false.
      - alacombe 6y ago
        > Is this really true and known empirically? Could the body be better at accessing calories in some foods and not others? Of course, 2000cal worth of HFCS is gonna have a different biological impact than 2000 cal worth of kale. CICO is a gross over-simplification.
- yazaddaruvala 6y ago
  > as far as I can tell, almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. I get it. I agree with you regarding the war. That said, as an individual that already tries to be healthy, I find the scientifically rigorous “how to do it better” is typically missing. I’m very grateful for a study like this, even if it’s not perfect and I need to extrapolate for a non-diabetic like myself.
- insickness 6y ago
  'Incredibly simple' answers and platitudes do an immense disservice to anyone trying optimize the effects of diet and exercise. For example, high-intensity interval training has been shown to be far more effective than low-intensity. And many have found a starvation diet is impossible to maintain and far less effective than a keto diet. It may seem like a waste of time to you, but this type of research can add up to important shifts in how we understand and maintain health.
  - wrycoder 6y ago
    Agreed. Gary Taubes has written three high quality books on the subject. The most technical and heavily referenced are Why We Get Fat and The Case For Keto. The latter was just published. I’ve been following a low glycemic diet for decades, but Taubes explains technically why it minimizes fat deposition. If I start eating snacks like candy or corn chips, the weight gain is immediate and obvious. Not all calories are the same - some foods just “go to your hips”.
    - Pinguinsan 6y ago
      Eating low carb and switching to high carb will cause significant water weight increase due to increased muscle glycogen. On the order of 5-10lbs. It's not fat.
      - wrycoder 6y ago
        That’s correct. For me, the effect is about four pounds. It comes off as fast as it went on. But if I continue to eat high carb, there is a weight gain that is much harder to shed.
        Pinguinsan 6y ago
        Are you saying that a diet from higher carbs will produce more fat gain than an equicaloric low carb diet?
        6y ago
- deleted 6y ago
  [deleted]
- LegitShady 6y ago
  > I understand the desire to investigate stuff like this, but for 90%+ of people, every inquiry in to "most optimal way to not be debilitating unhealthy" is just a waste of time. 95% of people won't program their exercise based on random studies, so I'm not sure what the conflict is. >almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. This is ultra naive. In the long term, 'wanting to improve' has to translate into compliance. getting people to want to improve is a short term thing that changes when you have to get up an hour early to run and shower, or whatever they choose. Getting people to comply long term is incredibly difficult. You can succeed in getting people to want to change and still fail long term compliance and get nothing. >Maybe that's just me, but I feel like we're searching for our keys under streetlight here. I don't think 'we' are one group, looking at only one group, for one particular reason. 'we' are an entire world full of people doing research for different reasons on different things.
- dirtyid 6y ago
  IMO health industry manufacturing trendy shifts from weak exercise science is large source of misunderstanding. Particularly when optimizations are exercises in minutiae. Fundamentally exercise + diet is simple but not easy. Not easy generally attributed to adherence and effort, but not easy also because individual response curves and almost every intervention works for some cohort while not others as you highlighted. What's really missing are better structured exercise plans that guides individual experimentation via roadmap from most effective -> least affective. Not major in minors, while constantly changing minors. Currently most people just bounce haphazardly from one fad to another, frequently mid-fad while biological processes from one response cause conflations.
- mam2 6y ago
  I agree thee kind of papers seem like a hairsplitting contest. Especially if you talk to people who ACTUALLY and SUCESSFULLY control their size... for (non hardocre) bodybuilder its pretty much IIFYM and for fighters who cut for fights its "just eat less bro, yes its hard.. are going to complain lol ?"
jb775 6y ago
I wonder if exercising at night has even better impacts. My jogs are usually sometime between 10pm-midnight. I recently mixed it up and went for a run in the late morning and it felt like I had lead feet...def impacted my body differently.
- elyobo 6y ago
  I cycle a moderate amount (~100km/week spread over 2-3 rides, typically in the 30-80km range), but drastically prefer starting early (generally pre-food, unless it's going to be a longer ~70km+ ride - in that case I know that I'll have to eat or I'll crash part way through). Feels far better.
  - vladvasiliu 6y ago
    I've also found that exercising in the morning, before eating, feels way better than at other times, especially in the evening. But I've also found that my "feeling" of a session doesn't necessarily correlate with the performance. I wouldn't be surprised for other benefits to have a similar correlation. However, as others have commented elsewhere, I think the issue for most people is not exercising at all, so for those cases the feeling you get while exercising absolutely matters. I'd say it's probably the most important thing, since if you feel like not exercising, you probably won't if it's not already ingrained in your routine.
    - elyobo 6y ago
      Yes, good point - my subjective feeling of effort is often at odds with my measured performance with Strava. And agreed on your second point too, I bike because I enjoy biking and it makes me feel better both physically and mentally. That I get good exercise out of it is a secondary benefit.

55 points by prostoalex 6y ago

This study appears to be specifically about people with Type 2 Diabetes. I wonder if the same holds true for healthy adults.

ac29 6y ago
And it was only men, and it was a rather small sample size (32 total, split 12 morning and 20 afternoon).

biren34 6y ago

I understand the desire to investigate stuff like this, but for 90%+ of people, every inquiry in to "most optimal way to not be debilitating unhealthy" is just a waste of time. If you're not in a special group (gout, hypertension, allergies, etc.) the answer is incredibly simple: - your diet determines your size - your activities (or lack thereof) determine your shape I realize that type 2 diabetics (as being studied in this paper) might be considered one of those groups, but as far as I can tell, almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. Maybe that's just me, but I feel like we're searching for our keys under streetlight here. These are easily studied problems, so there are papers/book written. Trying to understand the myriad psychological and societal (and possible environmental) processes is where the real gains will be made.

winstonchecksin 6y ago
>your diet determines your size - your activities (or lack thereof) determine your shape Damn. This is really well stated. With all the hundreds of fitness experts and personalities on the Internet and YouTube, it actually just comes down to this.
- klodolph 6y ago
  People also say "your body is made in the gym, but revealed in the kitchen". It's a bit of a simplification, but it requires so much exercise to burn the calories in a snack, it's easier to just not have the snack in the first place.
  - ImprovedSilence 6y ago
    similar, but we always used to say "abs are made in the kitchen, not in the gym".
  - codq 6y ago
    Yep. A blueberry muffin is around 424 calories. It takes about 45 minutes to burn that many calories jogging. Compare that to how many minutes it takes to simply not eat that muffin. A lot of people are afraid of the feeling of ‘hunger’; I find the sensation of hunger is actually a motivating one. I try to fast around 16 hours a day (eating window 12pm-8pm) and really think it keeps my head clear and helps me work, especially in the morning.
    - dvt 6y ago
      > I try to fast around 16 hours a day (eating window 12pm-8pm) I've been doing intermittent fasting for ~5 years now, and I don't even feel the hunger anymore. The only time I feel it is when I aggressively work out (running ~2 miles in the morning + lifting ~45 mins in the afternoon 5 days a week) and if I'm on a caloric deficit (~1750kcal). I also notice I get that hungry feeling particularly if my macros shift away from carbs (which they usually do when cutting weight). The human body is an incredible machine.
      - xupybd 6y ago
        Have you tried upping your fat when you are cutting? I find that my hunger tends to be controlled mainly by my fat intake.
        6y ago
DiabloD3 6y ago
Remember, diet composition effects size, not some weird obsession with "calories in calories out" in some non-scientific cargo cult way.
- kiba 6y ago
  Calories in, calories out absolutely work. Except that humans don't manage their diet by counting calories. We have regulatory mechanism that supposed to do the calories counting for us.
  - amanaplanacanal 6y ago
    Calories in calories out could help if you could accurately measure them. I suspect that most people can’t. But you are right, internal mechanisms regulate both hunger and activity levels.
    - kiba 6y ago
      The point is that we shouldn't need to count calories.
  - fighterpilot 6y ago
    > Calories in, calories out absolutely work. Is this really true and known empirically? Could the body be better at accessing calories in some foods and not others? Thought experiment: suppose I wrapped a small chocolate bar into airtight plastic, then I swallowed it. I have just swallowed 200 calories, but my body will access/process/burn 0% of it since it can't break down the plastic. At least in this one (unrealistic) example, CICO is false.
    - alacombe 6y ago
      > Is this really true and known empirically? Could the body be better at accessing calories in some foods and not others? Of course, 2000cal worth of HFCS is gonna have a different biological impact than 2000 cal worth of kale. CICO is a gross over-simplification.
yazaddaruvala 6y ago
> as far as I can tell, almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. I get it. I agree with you regarding the war. That said, as an individual that already tries to be healthy, I find the scientifically rigorous “how to do it better” is typically missing. I’m very grateful for a study like this, even if it’s not perfect and I need to extrapolate for a non-diabetic like myself.
insickness 6y ago
'Incredibly simple' answers and platitudes do an immense disservice to anyone trying optimize the effects of diet and exercise. For example, high-intensity interval training has been shown to be far more effective than low-intensity. And many have found a starvation diet is impossible to maintain and far less effective than a keto diet. It may seem like a waste of time to you, but this type of research can add up to important shifts in how we understand and maintain health.
- wrycoder 6y ago
  Agreed. Gary Taubes has written three high quality books on the subject. The most technical and heavily referenced are Why We Get Fat and The Case For Keto. The latter was just published. I’ve been following a low glycemic diet for decades, but Taubes explains technically why it minimizes fat deposition. If I start eating snacks like candy or corn chips, the weight gain is immediate and obvious. Not all calories are the same - some foods just “go to your hips”.
  - Pinguinsan 6y ago
    Eating low carb and switching to high carb will cause significant water weight increase due to increased muscle glycogen. On the order of 5-10lbs. It's not fat.
    - wrycoder 6y ago
      That’s correct. For me, the effect is about four pounds. It comes off as fast as it went on. But if I continue to eat high carb, there is a weight gain that is much harder to shed.
      - Pinguinsan 6y ago
        Are you saying that a diet from higher carbs will produce more fat gain than an equicaloric low carb diet?
        6y ago
deleted 6y ago
[deleted]
LegitShady 6y ago
> I understand the desire to investigate stuff like this, but for 90%+ of people, every inquiry in to "most optimal way to not be debilitating unhealthy" is just a waste of time. 95% of people won't program their exercise based on random studies, so I'm not sure what the conflict is. >almost all of the war is in getting people wanting to improve, and very little of it is in the how to do it. This is ultra naive. In the long term, 'wanting to improve' has to translate into compliance. getting people to want to improve is a short term thing that changes when you have to get up an hour early to run and shower, or whatever they choose. Getting people to comply long term is incredibly difficult. You can succeed in getting people to want to change and still fail long term compliance and get nothing. >Maybe that's just me, but I feel like we're searching for our keys under streetlight here. I don't think 'we' are one group, looking at only one group, for one particular reason. 'we' are an entire world full of people doing research for different reasons on different things.
dirtyid 6y ago
IMO health industry manufacturing trendy shifts from weak exercise science is large source of misunderstanding. Particularly when optimizations are exercises in minutiae. Fundamentally exercise + diet is simple but not easy. Not easy generally attributed to adherence and effort, but not easy also because individual response curves and almost every intervention works for some cohort while not others as you highlighted. What's really missing are better structured exercise plans that guides individual experimentation via roadmap from most effective -> least affective. Not major in minors, while constantly changing minors. Currently most people just bounce haphazardly from one fad to another, frequently mid-fad while biological processes from one response cause conflations.
mam2 6y ago
I agree thee kind of papers seem like a hairsplitting contest. Especially if you talk to people who ACTUALLY and SUCESSFULLY control their size... for (non hardocre) bodybuilder its pretty much IIFYM and for fighters who cut for fights its "just eat less bro, yes its hard.. are going to complain lol ?"

jb775 6y ago

I wonder if exercising at night has even better impacts. My jogs are usually sometime between 10pm-midnight. I recently mixed it up and went for a run in the late morning and it felt like I had lead feet...def impacted my body differently.

elyobo 6y ago
I cycle a moderate amount (~100km/week spread over 2-3 rides, typically in the 30-80km range), but drastically prefer starting early (generally pre-food, unless it's going to be a longer ~70km+ ride - in that case I know that I'll have to eat or I'll crash part way through). Feels far better.
- vladvasiliu 6y ago
  I've also found that exercising in the morning, before eating, feels way better than at other times, especially in the evening. But I've also found that my "feeling" of a session doesn't necessarily correlate with the performance. I wouldn't be surprised for other benefits to have a similar correlation. However, as others have commented elsewhere, I think the issue for most people is not exercising at all, so for those cases the feeling you get while exercising absolutely matters. I'd say it's probably the most important thing, since if you feel like not exercising, you probably won't if it's not already ingrained in your routine.
  - elyobo 6y ago
    Yes, good point - my subjective feeling of effort is often at odds with my measured performance with Strava. And agreed on your second point too, I bike because I enjoy biking and it makes me feel better both physically and mentally. That I get good exercise out of it is a secondary benefit.