When your body uses up the energy it takes to complete a hard workout, it’s like digging a hole. Before you can make any progress, that hole has to be filled back in—the energy you used has to be replaced. Once that’s over with, then, and only then, can your body over-compensate by building new muscle tissue.
Tip: Never work out 2 days in a row, and never more than 2-3 times per week. You will make faster progress, you’ll feel a lot better, and you’ll be more likely to stick with your program for the long term.