The Influence of Light Therapy on Recovery from Exercise-Induced Muscle Damage

Abstract

Introduction: Engaging in physical activity and exercise can result in muscle damage and soreness. When muscles lengthen under tension during eccentric contraction, which can happen during daily physical activities, it can cause exercise-induced muscle damage (EIMD). When you repeat those movements at a high intensity, intracellular muscle damage can occur leading to a 24 to 48-hour delay in the onset of muscle soreness (DOMS) (Choi, 2014). There have been products invented to enhance the recovery of DOMS created by EIMD. Light therapy (LT), in this case, is a non-invasive clinical technique commonly used to treat muscular injuries. The purpose of this study is to examine the effectiveness of LT on EIMD compared to a placebo group (PL) during an eight-day trial. Methods: Participants were divided into two groups (LT & PL) not knowing which group they were in (single-blind experiment) and were tested on their range of motion (ROM) on their hip flexion and abduction, their perception of muscle soreness (GLMS scale), vertical jump, and agility (T-test). To induce muscle damage, participants ran 40 15-meter sprints with a 5-meter deceleration zone, thereafter, commenced the LT treatment on the fourth day on. LT was applied to the quadriceps, hamstring and calf muscles on both legs. We hypothesized LT following EIMD would neither influence perceptions of muscle soreness, flexibility, vertical jumping ability, nor agility, compared to a placebo treatment group. Discussion/Conclusion: A significant difference (p < .05) was found between the two groups in the measurement of calf soreness. The LT group reported lower calf soreness level throughout the week. No other significant differences were found between groups. This data lends itself to the theory that light therapy is more beneficial for treating soreness in Type I muscle fibers.