If young, healthy guys do certain muscle-lengthening exercises before having one leg kept still for a week, their muscles don’t slow down making new proteins as much as those who don’t exercise — which might help prevent muscle loss.

If young, healthy guys do a tough leg workout right before having one leg immobilized for a week, their muscles in that leg keep building protein faster for the first couple of days compared to if they didn’t exercise first.

If young, healthy guys do certain muscle-damaging exercises before their leg is immobilized, their muscles might waste away less—even if their muscle-building activity goes down. Without those exercises, lower muscle-building activity means more muscle loss.

After 10 weeks of working out, men who are already somewhat active don't build muscle as efficiently as before, and their bodies don't respond as strongly to exercise—this happens whether they're doing cardio or weight training.

Doing a tough leg workout with lots of sets makes your leg muscles start building new proteins much faster—2 to 3 times more than usual—right after the workout.

If young, healthy guys do certain tough leg exercises before keeping one leg still, they might avoid losing muscle in that leg during the first couple of days of not using it.