Making Bodyweight Exercises More Challenging
The traditional bodyweight exercises are effective for improving muscle strength and endurance, although not as productive as progressive resistance exercises performed with free-weights or weight-stack machines. In "Making Bodyweight Exercises More Challenging" Wayne Westcott, Ph.D. suggests using slower movement speeds to reduce the role of momentum and force the muscles to work a lot harder. He presents details for using this technique with the five most common bodyweight exercises - knee-bends (squats), trunk curls, push-ups, bar-dips and chin-ups....  

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