Leg extensions may very well be the most objectionable exercises in health and fitness. Some people object to the fact that they’re not functional, while others imply that they can cause ligament damage, or create knee pain around the patella. Sometimes people dislike them, simply because others dislike them.
But are leg extensions really bad? Actually, no. For example, no studies have documented people tearing ligaments while doing leg extensions, and while knee pain is a risk with all lower body activities, it can be avoided on leg extensions by limiting the motion to the very last 20 degrees of knee extension.
On the other hand, there is good scientific evidence that leg extensions improve lower body strength and function. They help develop the quadriceps muscles, which are important contributors to running and jumping, and some studies have even shown that leg extensions help to improve function in patients with ACL-deficient knees.
The truth is that leg extensions are really beneficial exercises, which should be a part of any complete, lower body strength program. If you want to learn more about leg extensions, read the full article here: The Truth on Fitness: Leg Extensions.
Paul M. Juris, Ed.D.
Executive Director, CYBEX Institute for Exercise Science
Dr. Juris earned his Doctorate in Motor Learning from Columbia University in 1993, followed by a variety of positions in higher education, rehabilitative medicine, professional sports, and fitness. Paul Juris, Ed.D. was named Executive Director of the CYBEX Institute for Exercise Science in January of 2007.