The leg press is an exercise that can do one of two things: build up your thigh muscles or help you develop more leg stamina. To do the latter, you need low weight and a lot of reps. If you want to build mass, you want to lift as much weight as you can. To do this, you'll need to find your max weight for the leg press. To get this number, you'll need to work by trial-and-error, but that doesn't mean you have to start at zero.
Load the leg press machine with enough weight equal to your body weight. You already know that your legs support your body weight. Whatever your max weight is, it's a good deal more than the weight of your body. Most healthy, active people can lift at least 20 percent more than their body weight on the leg press, so if you're comfortable with your fitness level, add an extra 20 percent of your body weight to the leg press rack.
Sit back into the machine's chair and then press up on the foot pad with your legs. Grip the safety handles, but keep the safety engaged. If you feel that your legs can't hold up the weight, your knees will buckle, or you have to lock your knees to keep the weight up, lower the foot pad back to the safety bar. Decrease the weight and then try again. If it feels too light, increase the weight until you have slight difficulty keeping the weight up without locking your knees.
Release the safety bars and try one rep. Control the motion steadily all the way until your knees are just above your chest and then slowly return the weight to starting position. Do a second rep and then when you're done, see if you can do a third. If you can, increase the amount of weight until that third rep becomes nearly impossible.
- Rest at least one full day between workouts in which you lift to complete muscle failure when doing max-weight exercises.
- Always work with a spotter when you're trying to find your max weight for any lifting exercise. Keep your hands on the safety handles at all times.
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