Exercise-Induced Muscle Damage: Is it detrimental or beneficial?

decline in force and increased soreness following exercise of the finger flexors 1. In the early 1980’s research on this exercise-induced muscle damage (EIMD) noted by Dr. Hough began to considerably increase. Newham et al.2 investigated EIMD using electron microscopy and found significant changes in muscle structure immediately after exercise, and the number of damaged fibers continued to increase after 30 hours. Furthermore, cases of extreme muscle damage, such as rhabdomyolysis, following exercise could potentially lead to life-threatening problems such as acute kidney failure and hypokalemia 3. Deciphering the mechanisms behind EIMD has been perplexing and is still not completely understood despite the many years of research. Because of the negative effects of EIMD many researchers have sought to decrease the amount of muscle damage after a damaging bout of exercise but few prophalytic interventions have proven effective 4. Interestingly, one of the most powerful protections against muscle damage is a preceding damaging exercise bout 4 which raises the question, is muscle damage detrimental or beneficial? This is a pertinent question to many people who train recreationally or who train for exercise competitions. Some may have the idea that muscle damage is necessary for maximal gains or others may feel that it should be avoided altogether. Thus, the purpose of this brief review will be to discuss some of the detrimental effects of muscle damage and to examine if muscle damage is needed to provide beneficial adaptations such as the repeated bout effect or muscle hypertrophy. Muscle damage mechanisms