Vary Your Volume
Heavier isn't always better. To maximize gains, Lautner regularly varies reps and the amount of weight he lifts. "If you want a balanced body, you have to do that," says Yuam. The more your muscles are forced to adapt to a new routine, the more they grow. Instead of always doing 3 sets of 8 to 10 reps, for example, occasionally reduce the weight and shoot for 4 sets of 15 reps. A recent study in the Journal of Strength and Conditioning Research found that men who regularly varied their rep counts and trained different muscle groups increased their bench strength by 28 percent and their leg-press strength by 43 percent.
Source: Men's Health