Patrick Smith said:I have a question about exercise and diet. Warning: This may be an astoundingly stupid question.If nutrition is pretty much the number one factor in whether you get lean, does that mean it's as simple as how much you eat, what you eat, and when you eat it?
If so, than regardless of whether you exercise more or less, if you're eating as much or as little as the exercise demands, you can't really speed up the recomposition rate can you? I mean, if the amount of food that you eat is constant with the amount of exercise you do (so you don't fall into too much deficit or excess).
If that's true, I guess that makes sense; however, surely exercise has physiological benefits that would increase the rate of recomp outside of kcal in/kcal out. What are these?
Anyone feel free to pitch in.
That's how it works, but there are a number of factors here.
When you eat what you need, your metabolism runs at full speed. Already, that is an advantage.
Exercise makes your tissues more sensitive to insulin, which ends up dramatically lowering serum insulin levels as well as how much insulin is required to push all the food into your cells when you eat. The lower your serum insulin levels are and the smaller the required insulin response to food, the less fat mass you accumulate with the same caloric load. In other words, lower insulin levels = less fat storage.
Food + exercise = more lean mass, which = higher metabolism, which = more potential for fat loss and less potential for fat gain.
Finally, exercise is awesome because no matter what you do, a significant amount of body fat is utilized. That is part of why having less fat and more carbs works so well. You don't want your body running primarily off of dietary fat if you are trying to specifically burn body fat, right? If you aren't consuming EXCESS carbs, you aren't going to be generating as much body fat as you burn off.
Example: You burn 400 calories while running. Lets say 50% of that is from fat. You eat 400 calories to stay in energy balance. The meal is 70g carbs and 20g protein and 5g fat. You are replacing 50g of carbs, with 20g left over. Assuming that 40% of those excess carbs go to fat, that's 8g of carbs. 32k calories. 3.5g of fat or so got added. You burned 200 kcal of fat. 22.2g of fat. Net loss of 18.7g of fat that you would not have lost otherwise. That's an extra .04 lbs, so 24 of those sessions are required to burn an extra 1 lb of fat or so. Now, the truth is that nearly 0% of that meal is going to go to fat so you are really going to lose almost all 22.2g of that fat burned during exercise.
Between that and what you can do by staying in energy balance while spending more time in small deficit than small surplus, it is reasonable to expect 1 lb of fat loss per 7-10 days with a 12-15% body fat. That's what, 3-4 lbs? with just that small amount of exercise it becomes 4-5 lbs, a 25-33% increase in fat loss from a small amount of exercise at a sustainable pace that allows for lean mass to be preserved and slowly increased at the same time. Remember, if you are eating for the same weight and dropping body fat, you are eating enough energy for more lean mass to exist and so you will recompose accordingly.
