Impact of static stretching on the gain in knee-extensor strength of community-dwelling older women after a training program

Background: The decrease in muscle strength in older adults has an impact on functionality. Muscle strengthening programs have been proposed, however there is some controversy surrounding the effects of stretching prior to strengthening exercises on muscle strength gain. Objective: To verify the impact of static stretching on the gain in knee-extensor strength of community-dwelling elderly women after a training program. Methods: This was a quasi-experimental study that included a ten-week knee-extensor strengthening program and a final assessment of 12 community-dwelling elderly women divided into two groups: group SE - strengthening exercises with prior static stretching in all sessions, mean age 73.8 ( plus or minus 5.36) years; and group E - same strengthening exercises as SE without prior stretching, mean age 72.14 ( plus or minus 5.43) years. To measure knee-extensor strength gains, we used the isokinetic dynamometer Biodex System 3 Pro, in concentric mode at angular velocities of 60 degree and 180 degree /s, and for statistical analysis we used the difference between pre- and post-intervention means of work adjusted by body weight. Results: The data showed normality in the Shapiro-Wilk test (p>0.266). When comparing the differences between the pre- and post-intervention means using the t test for independent samples, there was no significant difference in any of the limbs at the velocities evaluated (p>0.383). Conclusion: Previous static stretching did not interfere in muscle strength gain following a ten-week muscle strengthening program in the population studied.Original Abstract: Contextualizacao: A diminuicao da forca muscular em idosos tem impacto na funcionalidade. Programas de reforco muscular sao propostos, porem existem controversias quanto ao efeito de alongamentos previos no ganho de forca muscular. Objetivo: Verificar o impacto do alongamento estatico no ganho de forca dos musculos extensores de joelho em idosas da comunidade apos programa de treinamento. Metodos: Trata-se de um estudo quase-experimental, em que se realizou um programa de exercicios de fortalecimento muscular dos extensores de joelho durante 10 semanas, com avaliacao final de 12 idosas da comunidade divididas em dois grupos: AE - exercicios com carga e alongamentos previos em todas as sessoes, media de idade de 73,8 ( plus or minus 5,36) anos e E - mesmos exercicios com carga do grupo acima, sem a realizacao de alongamentos previos, media de idade de 72,14 ( plus or minu