Although handgrip strength is considered a strong predictor of negative health outcomes, it is unclear whether handgrip strength represents a useful measure to evaluate changes in muscle strength following resistance-type exercise training in older people. We assessed whether measuring handgrip strength provides proper insight in the efficacy of resistance-type exercise training to increase muscle mass, strength, and physical performance in frail older people.
Prefrail and frail older people (≥ 65 y) were either conducting a 24-week resistance-type exercise training or no exercise training. Before, during, and after the intervention, handgrip strength (JAMAR), lean body mass (DXA), leg strength (1-RM), and physical performance (SPPB) were assessed.
Handgrip strength correlated with appendicular lean mass (r = 0.68; p < .001) and leg strength (r = 0.67; p < .001). After 24 weeks of whole body resistance-type exercise training, leg extension strength improved significantly better when compared with the control group (57 ± 2–78 ± 3 kg vs 57 ± 3–65 ± 3 kg: p < .001). Moreover, physical performance improved significantly more in the exercise group (8.0 ± 0.4–9.3 ± 0.4 points) when compared with the control group (8.3 ± 0.4–8.9 ± 0.4 points: p < .05). These positive changes were not accompanied with any significant changes in handgrip strength (26.3 ± 1.2–27.6 ± 1.2 kg in the exercise group vs 26.6 ± 1.2–26.3 ± 1.3 kg in the control group: p = .71).
Although handgrip strength strongly correlates with muscle mass and leg strength in frail older people, handgrip strength does not provide a valid means to evaluate the efficacy of exercise intervention programs to increase muscle mass or strength in an older population.
The authors are with Top Institute Food and Nutrition, Wageningen, Netherlands.