Progressive Resistance Training Improves Torque Capacity and Strength in Mobility-Limited Older Adults.

BACKGROUND

Progressive resistance training (PRT) is consistently shown to improve muscle strength in older adults. The efficacy of PRT to improve muscle fatigue in older adults with demonstrated mobility limitations remains unclear.

METHODS

Mobility-limited (Short Physical Performance Battery [SPPB] ≤ 9) older adults (age 70-92 years) were recruited for this study and randomized to either PRT or home-based flexibility (FLEX) 3 d/wk for 12 weeks. Muscle fatigue and strength outcomes were assessed at baseline and 12 weeks. The primary outcome was torque capacity, a composite measure of strength and fatigue, defined as the sum of peak torques from an isokinetic fatigue test.

RESULTS

Seventy participants were randomized (mean [SD] age 78.9 [5.4] years; 60% female; mean [SD] SPPB 7.5 [1.6]). At follow-up, the PRT group improved significantly in torque capacity, mean between-group difference (95% confidence interval) 466.19 (138.4, 793.97) Nm (p = .006), and maximal strength 127.3 (60.96, 193.61) Nm (p = .0003), when compared with FLEX group. Neither group demonstrated significant changes in muscle fatigue or torque variability.

CONCLUSION

Twelve weeks of PRT improved torque capacity, as well as strength in mobility-limited older adults. These results demonstrate PRT improves multiple age-related muscular impairments.