Keep your weight workouts to 30 minutes. After 30 minutes, your body starts producing more of the stress hormone cortisol, which can have a testosterone-blocking, muscle-wasting effect.

 

 

Don’t work your abdominal muscles every day. “Physiologically, your abs are like any other muscle in your body,” says David Pearson, Ph.D., C.S.C.S., an exercise scientist at Ball State University. Train them only 2 or 3 days a week.