Abstract
Active lifestyle is important for all age groups, especially essential among older adults to counter balance the deleterious effects of aging. Scientific literature is scarce about the effect of Proprioceptive Neuromuscular Facilitatio (PNF) stretching on older adults. Therefore, the purpose of this study is to find out the effect of self-administered CRAC stretching on the performance of hamstring curls to fatigue in older adults. We used the same subject repeated measure experimental crossover design, where subjects were randomly allocated into two groups and both the groups were given the Self-Administered CRAC stretching in alternate session to overcome the order effect. The result of this present study demonstrated that there was a significant between-group effect (t = -2.06, p=0.0484) seen. The participants getting CRAC stretching performed 37% and 44% less hamstring curls to fatigue in the respective sessions. In summary, our primary findings indicated enhanced flexibility with an accompanying decrease in the number of hamstring curls performance in response to self-administered CRAC stretching. These findings are unique in that, to our knowledge, no other authors have examined the effects of CRAC stretching on isolated muscle performance with a repeated measures design. Regarding the mechanisms underlying the stretching-induced performance deficit, the decreases in no of hamstring curls we observed in our study tentatively support the hypothesis that stretching may alter the length-tension relationship and the hypothesis that stretching may reduce muscle activation, respectively. CRAC stretching can be made part of a full warm-up routine because of its positive impact on flexibility and musculotendinous injury occurrence in the physically active older population.