There are a few important things to consider with your first lifting efforts. Learn the big lifts. Deadlift, Squat, Overhead Press, (Benchpress, if you have an

There are a few important things to consider with your first lifting efforts. Learn the big lifts. Deadlift, Squat, Overhead Press, (Benchpress, if you have an environment to do it). To min/max your workout, all you have to do is work the biggest muscles. That gains you the most benefit for the least amount of time. I would also point out there is a bit of a misconception about "noob gains". When starting out, and or, especially losing weight it definitely helps prevent the loss of muscle mass. But, and this is a big but, a huge amount of your initial gains in the amount of weight you can move around are not from gained muscle mass. They are from central nervous system (CNS) adaptation. Your muscles simply don't know how to fire at maximum intensity. Much of your first 6-12 months gains in terms of weight moved around are just CNS adaptation. Your body recruits more muscle fiber for activities. Folks can move a startlingly larger amount of weight without gaining virtually any amount of muscle. Once you have reached a local maximum for this sort of adaptation you start gaining more muscle mass. Of course, if you lift weights and eat at a surplus you do build some muscle mass, but not nearly as much as after a decent period of lifting. Finally, if you are eating in a calorie deficit you will not be adding muscle mass without a very carefully controlled diet that most fitness and diet novices don't have the knowledge and discipline to pull off. To actually live at a calorie deficit (lose body fat), preserve and or gain muscle mass, you have to move your calories around constantly (deficit weeks, surplus days with focused intense lifting, etc.). It is incredibly hard for someone just embarking on a fitness journey to adhere to a diet that includes surplus weeks in my experience. It just leads to a general lack of adherence and a slide back to old habits. Also, 1000 calories (per day) is definitely at the edge, but not crazy (7k / week, about 2lbs per week). I would say that is at the limit of what is medically advisable, but not crazy. Especially if you are above 250 lbs, that is not a crazy percentage of your weight. If you have enough body fat to lose, aim for something like a 1% reduction in body fat (assuming you are around 200 lbs, start at a lower percentage if you are heavier, no more than 2lbs / week no matter what). Then every few weeks you have to crank the dial down. Fat burns some calories to maintain itself and your body adapts and tries a little harder to hang onto energy stores. Dialing down the calorie deficit over a 18-12 month period in a very controlled fashion almost assures you will never "stall out" over the long run. Final random tidbit to share, use weight trend, not actual weight, to measure progress. Without an extremely consistent diet the amount of water your body caries can vary by several pounds, but trending the weight over a 1-2 week period almost assures you will measure actual progress and not how much water your body is holding a given day. edit: clarity on deficit amounts.