A comprehensive guide to max out your gains and fill out your shirtsleeves, according to exercise experts.

You're currently following this author! Want to unfollow? Unsubscribe via the link in your email. Don't let a busy schedule stop you from building muscle — just four weekly sets of exercise per muscle ...

If you have ever lifted a weight, you know the routine: challenge the muscle, give it rest, feed it and repeat. Over time, it grows stronger. Of course, muscles only grow when the challenge increases ...