A Greater Reduction of Anterior Cruciate Ligament Elasticity in Women Compared to Men as a Result of Delayed Onset Muscle Soreness

A Greater Reduction of Anterior Cruciate Ligament Elasticity in Women Compared to Men as a Result of Delayed Onset Muscle Soreness

HANEUL LEE,¹ JERROLD S. PETROFSKY,¹ MICHAEL LAYMON² and JONGEUN YIM³

¹Department of Physical Therapy, School of Allied Health Professions, Loma Linda University, Loma Linda, CA, USA
²Department of Physical Therapy, Touro University Nevada, Henderson, NV, USA
³Department of Physical Therapy, Sahmyook University, Seoul, Korea

Women have a higher risk for anterior cruciate ligament (ACL) injuries compared to men. ACL elasticity and muscle flexibility are major risk factors for knee injuries. The presence of estrogen receptors in connective tissue allows estrogen to change the mechanical properties of muscles and ligaments. Delayed onset muscle soreness (DOMS) happened when begin unaccustomed levels of exercise. Thus, the purpose of this study was to examine ACL elasticity after exercise meant to produce DOMS. As a measure of DOMS, visual analog pain scale and quadriceps strength were measured. One hundred forty healthy students (age: 25.2 ± 2.4 years, height: 165.9 ± 8.0 cm, weight: 62.5 ± 10.5 kg, BMI: 22.6 ± 3.1) participated in this investigation and were divided into two groups: men (n = 70) and women (n = 70). Visual analog pain scale, ACL elasticity, and quadriceps strength were measured before and after the intervention. Subjects participated in the same exercise to induce DOMS. To provoke DOMS, subjects accomplished squats for 5 minutes for 3 rounds. Greater ACL elasticity, greater pain on the subjective pain scale and less muscle strength were found (p < 0.001) in women compared to men before and after exercise. A greater reduction of ACL elasticity (p < 0.05) was found as a result of DOMS in women compared to men. Women are likely to have the damage to the ACL and recover slower compared to men after exercise. Thus, we suggest that women should have more time for musculoskeletal recovery after heavy exercise.

keywords —— anterior cruciate ligament elasticity; delayed onset muscle soreness; high-induced exercise; quadriceps strength; sex difference

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Tohoku J. Exp. Med., 2013, 231, 111-115

Correspondence: Jerrold Petrofsky, Department of Physical Therapy, Loma Linda University, Loma Linda, California 92350, USA

e-mail: jpetrofsky@llu.edu