The improvement in walking speed induced by resistance training is associated with increased muscular strength but not skeletal muscle mass in older women.

OBJECTIVE: The purpose of the present study was to analyze whether improvements in fast walking speed induced by resistance training (RT) are associated with changes in body composition, muscle quality, and muscular strength in older women.

METHODS: Twenty-three healthy older women (69.6 ± 6.4 years, 64.95 ± 12.9 kg, 1.55 ± 0.07 m, 27.06 ± 4.6 kg/m²) performed a RT program for 8 weeks consisting of 8 exercises for the whole body, 3 sets of 10-15 repetitions maximum, 3 times a week. Anthropometric, body composition (fat-free mass [FFM], skeletal muscle mass [SMM], legs lean soft tissue [LLST], fat mass), knee extension muscular strength (KE1RM), muscle quality index (MQI [KE1RM/LLST]), and 10-meter walking test (10-MWT) were performed before and after the intervention.

RESULTS: Significant (P < .05) changes were observed from pre- to post-training for FFM (+1.6%), MQI (+7.2%), SMM (+2.4%), LLST (+1.8%), KE1RM (+8.6%), fat mass (-1.4%), and time to perform 10-MWT (-3.7%). The percentage change in 10-MWT was significantly associated with percentage change in MQI (r = -0.46, P = .04) and KE1RM (r = -0.45, P = .04), however not associated percentage of changes in SMM (r = 0.01, P = .97), LLST (r = -0.22, P = .33), and body fat (r = 0.10, P = .66).

CONCLUSION: We conclude that the improvement in the 10-MWT after an 8-week RT program is associated with increases in lower limb muscular strength and muscle quality, but not with muscle mass or body fat changes in older women.