Effect of Eight-Week Strength Training on Body Composition, Muscle Strength and Perceived Stress in...

Background: Sarcopenia, characterized by loss of muscle mass, strength, and function, reduces independence and quality of life in older adults. Strength exercise (STR) mitigates these age-related declines, but evidence of short-term effectiveness remains limited. This study aimed to evaluate the effects of eight weeks of STR on body composition, muscle strength, and psycho-emotional state in community-dwelling elderly women. Methods: A prospective, controlled, non-randomized study included 44 women assigned to an STR (n = 20) or control (CON, n = 22) group. The STR group performed supervised exercise twice weekly for eight weeks. The outcomes were body composition, handgrip strength (HGS), quadriceps (Q) and hamstrings (H) strength, and perceived stress (PSS-10), assessed at baseline and after intervention. Within-group changes were analyzed using paired t-tests, and between-group differences were evaluated using analysis of covariance (ANCOVA) adjusted for baseline values. Results: After baseline adjustment, body mass (p = 0.041, partial η² = 0.103), BMI (body mass index, p = 0.030, partial η² = 0.115), and body fat percentage (p = 0.047, partial η² = 0.098) were significantly reduced in the STR group. Significant improvements were observed for H strength in both legs (p < 0.05, partial η² = 0.128-0.131), right HGS (p = 0.025, partial η² = 0.122), right HGS:BMI ratio (p = 0.013, partial η² = 0.150), and H:Q ratios on both sides (p < 0.05, partial η² = 0.109-0.118). No significant differences were observed for left-hand grip strength, knee extensor strength, or other body composition variables (p > 0.05). The perceived stress scores were significantly lower in the STR group post-intervention (p = 0.036, partial η² = 0.108). Conclusions: An eight-week supervised strength exercise program was associated with favorable changes in muscle strength, body composition, and psycho-emotional state in elderly women.