To compare cruciate ligament forces during wall squat and one-leg squat exercises.
Eighteen subjects performed the wall squat with feet closer to the wall (wall squat short), the wall squat with feet farther from the wall (wall squat long), and the one-leg squat. EMG, force, and kinematic variables were input into a biomechanical model using optimization. A three-factor repeated-measure ANOVA (P < 0.05) with planned comparisons was used.
Mean posterior cruciate ligament (PCL) forces were significantly greater in 1) wall squat long compared with wall squat short (0°-80° knee angles) and one-leg squat (0°-90° knee angles); 2) wall squat short compared with one-leg squat between 0°-20° and 90° knee angles; 3) wall squat long compared with wall squat short (70°-0° knee angles) and one-leg squat (90°-60° and 20°-0° knee angles); and 4) wall squat short compared with one-leg squat between 90°-70° and 0° knee angles. Peak PCL force magnitudes occurred between 80° and 90° knee angles and were 723 ± 127 N for wall squat long, 786 ± 197 N for wall squat short, and 414 ± 133 N for one-leg squat. Anterior cruciate ligament (ACL) forces during one-leg squat occurred between 0° and 40° knee angles, with a peak magnitude of 59 ± 52 N at 30° knee angle. Quadriceps force ranged approximately between 30 and 720 N, whereas hamstring force ranged approximately between 15 and 190 N.
Throughout the 0°-90° knee angles, the wall squat long generally exhibited significantly greater PCL forces compared with the wall squat short and one-leg squat. PCL forces were similar between the wall squat short and the one-leg squat. ACL forces were generated only in the one-leg squat. All exercises appear to load the ACL and the PCL within a safe range in healthy individuals.
1Department of Physical Therapy, California State University, Sacramento, CA; 2The Center for Biomedical Engineering, Department of Mechanical Engineering and Engineering Science, University of North Carolina, Charlotte, NC; 3Kinesiology and Health Science Department, California State University, Sacramento, CA; 4Department of Physical Therapy, Center for Biomedical Engineering Research, University of Delaware, Newark, DE; 5Department of Kinesiology, Iowa State University, Ames, IA; 6American Sports Medicine Institute, Birmingham, AL; 7Champion Sports Medicine, Birmingham, AL; 8Duke Sports Medicine Center, Duke University, Durham, NC; and 9Andrews Research and Education Institute, Gulf Breeze, FL
Address for correspondence: Rafael F. Escamilla, Ph.D., P.T., C.S.C.S.,FACSM, Professor, Department of Physical Therapy, California State University, Sacramento, 6000 J Street, Sacramento, CA 95819-6020; E-mail: firstname.lastname@example.org.
Submitted for publication September 2007.
Accepted for publication July 2008.