Sport Supplement effect on treatment of delayed onset muscle soreness (DOMS)

It is well documented that exercise, including resistance exercise consisting of lengthening (eccentric) contractions, causes muscle damage and discomfort compounded with DOMS, and edema may be lasted over time chronically. Although several factors including lactic acid accumulation, connective tissue damage surrounding muscles, increased muscle temperature, muscle spasm, inflammatory responses, free radicals generation, and concentration of nitric oxides have been suggested for causing DOMS, there is no clear explanation (1).Previous literatures have speculated that the cause of DOMS is due to structural muscle damages and perturbation of calcium homeostasis or acute inflammatory responses to exercise. Thus, DOMS may occur with numerous complex factors combined after exercise-induced muscle damage. By gathering the results from previous studies, DOMS is found to be caused by exercise induced muscle damage.Ways to reduce DOMS have been studied extensively, and many studies have reported on nutrition interventions to reduce DOMS. The purpose of this review is to provide guidelines and information about DOMS for the sport nutritionists in the practical field so that they can confidently select Sport Supplement based interventions.BCAA: Acute ingestion of 50g of BCAAs resulted in significantly lower CK (Creatine Kinase) and pain levels following a cycling protocol. Another study also showed that a single high dose of BCAAs (100 mg/kg) immediately before resistance exercise, significantly attenuated DOMS (2). We concluded that DOMS was reduced by an ingestion of either BCAA drink or whey protein drink however; whey protein was significantly resulted in better outcomes (3). We also came to the conclusion that compared with combined BCAA, Isoleucine or Valine; Leucine provides a more protective effect on attenuating the immediate increase in biochemical markers of muscle damage following eccentric based resistance exercise, while combined BCAA may aid to maintain the range of motion (4). Further studies are required to assess the effect of different dosage of BCAA intake on muscle damage indices.HMB: HMB administrated 30 min prior to an acute bout of high-volume resistance training was able to attenuate indices of muscle damage and it could also improve perceived recovery in resistance-trained athletes (5). In another study, we concluded that 4 weeks HMB supplementation significantly decreases pain and blood marker of exercise-induced muscle damage (6). The mechanisms of HMB’s effects on muscle damage have not yet been fully clarified. Interestingly, previous researches on resistance training reported that HMB supplementation could decrease inflammatory biomarkers. Accordingly, HMB may exert its effects on muscle via immunomodulation of the damage and repair/remodeling cycle in response to acute and chronic resistance exercise (6).Whey protein and Carbohydrates: The Intake of 1.25g/kg CHO-Whey immediately and two hours after an eccentric resistance exercise has beneficial effects on muscle damage and proteolysis. In one of our research, the intake of 6 weeks Whey protein 35gr/day accompanying with resistance training could reduce DOMS (7). In another study, the intake of CHO-Whey (6.2% CH) & 1.5% Whey) before, during and after resistance training could reduce pain, CK and Mb (Myoglobin). In a study between two groups who have used iso-calorie CHO or CHO-Whey drinks during resistance exercise, the severity of muscle pain in CHO-Whey Group was also significantly less (8).Evidences show that the intake of Whey protein, due to high biological value, increases the accessibility of amino acids and the intake of carbohydrate provides a suitable hormonal environment to increase proteinsyntes and preventing proteolysis via insulin function. In another study that we have carried out on 24 young non-trained men, it was shown that the intake Whey: CHO (1:3 – 1:4) respectively could reduce the muscle damage and DOMS, but there were not any significant differences between two groups (9). Glutamine: The 24% reduction Glutamine plasma intensity has been reported 3 days after eccentric exercise. Glutamine supplementation on rats could reduce CK. In another study that we have carried out on 80 young non-trained men, it was shown that the intake of 0.1g/kg Glutamine doesn’t have a significant effect on CK, however it improved the reduction on muscle pain and the range of motion (10).Conclusions: DOMS that occurs after exercise-induced muscle damage contributes to the reduction in exercise performance as well as psychological complaints. In this review, several nutritional interventions were discussed to prevent or treat DOMS. Many studies have examined the effect of BCAAs, HMB, Whey protein, and polyphenol on DOMS, while minor interventions with glutamine and ginseng did not report consistent data. Many factors including study design, dose used, ingestion period, and markers to be measured to identify the hypotheses may affect the results.