Sok Park

Sarcopenia affects tens of millions of adults worldwide, with a reported prevalence of 10-50% among older adults. A decrease in muscle strength and function due to aging reduces physical performance, causing pain and disease. Accordingly, interest in the treatment or prevention of sarcopenia through resistance exercises, which have been found to be effective in improving muscle strength and hypertrophy, is increasing. However, given the individual differences, it is difficult to determine the optimal RE method. Currently, the importance of personalized resistance exercise (RE) prescriptions is emphasized, and research on sex/gender differences needs to be conducted. Our review focused on the effects of resistance exercise on muscle strength, muscle hypertrophy, and muscle function in older adults in relation to sex differences. In this review, we aimed to analyze sex differences in the effect of RE on older adults with sarcopenia and provide meaningful information for future research on exercise programs for individuals with sarcopenia.

The aim of this study is to compare differences in gait parameters such as gait speed, step length, step length-to-height ratio (SLR), and locomotor rehabilitation index (LRI) between sexes by age groups. In total, 354 subjects (aged 15-86 years) were divided into six groups by their age such as ‘≤29,’ ‘30–39,’ ‘40–49,’ ‘50–59,’ ‘60–69,’ and ‘≥70’ to compare the difference in gait parameters between sexes over the life span. Gait parameters were measured using a Global Positioning System (GPS) based smart shoes system including insole-type pressure sensor. According to the analysis, there were significant interaction effects in gait speed, SLR, and LRI between sexes and the age groups (all p < .05). There were significant differences among the age groups in gait speed (p < .001), step length (p < .001), SLR (p < .01), and LRI (p < .001) in women, and there was a significant difference among the age groups in gait speed (p < .001) and LRI (p < .001) in men. Especially, there was a significant difference in gait speed (p < .01) and LRI (p < .05) between ‘50–59’ and ‘60–69’ age groups in women. Also, body mass index (BMI) was negatively associated with all gait parameters in women, while there were no significant correlations between BMI and gait parameters in men. Taken together, the patterns of change in gait speed may be different between sexes over the life span. In particular, the gait speed may significantly decrease as women get old from middle age to old age, and obesity can be negatively associated with gait parameters in women.

PURPOSE: The present review aimed to verify the meta-effects of resistance training (RT) or protein supplementation (PS) on usual gait speed (UGS) in postmenopausal women and the additive effect of RT and PS on UGS.METHODS: A systematic literature search of PubMed/Medline and Web of Science (core collection) was performed from inception to December 31, 2021. Electronic search methods were used to identify 18 relevant randomized controlled trials. Meta-analyses of standardized mean difference (SMD) calculated using Hedges’ g between RT and/or PS groups versus control groups were conducted using a random-effects model. The meta-effects are presented in a forest plot with a 95% confidence interval (CI).RESULTS: The meta-analysis showed that RT significantly improved UGS (SMD, 0.40; 95% CI, 0.12-0.68; p=.006), while PS did not improve UGS (SMD, -0.17; 95% CI, -0.80 to 0.46; p=.601). A subgroup analysis indicated that there were significant increases in UGS after both ‘RT-only intervention (SMD, 0.30; 95% CI, 0.01 to 0.59; p=.046)’ and ‘RT combined with balance training (BT) (SMD, 0.65; 95% CI, 0.17-1.13; p=.008)’, while there was no significant increase in UGS after ‘RT combined with power training (PT) (SMD, -0.08; 95% CI, -0.62 to 0.45; p=.765)’. There was no additive effect on UGS after RT combined with PS (SMD, -0.06; 95% CI, -0.36 to 0.24; p=.699).CONCLUSIONS: This study revealed that RT significantly improved UGS in postmenopausal women, and adding BT to RT further improved UGS. In addition, there was no significant improvement in UGS after PS in postmenopausal women, and no additive effect on UGS after RT combined with PS.