Body mass-normalized handgrip strength as a better indicator of general health than absolute values in middle-aged women

Objectives: To examine the association between HGS and physical function, quality of life (QoL), and cardiometabolic risk markers in midlife women, and verify potential discrepancies between absolute and relative HGS on these relationships. Study design: This cross-sectional study enrolled 83 participants (50.7±5.3y) who completed handgrip (hydraulic dynamometer), knee extensor and plantar flexor (isokinetic dynamometry) strength tests, and body composition evaluations (DXA). A variety of physical function tests, QoL (SF-36) and cardiometabolic blood markers were also measured. Results: Participants below the cutoff for HGS/body mass (0.34) did not differ in height but were significantly (P<0.01) heavier (80.8±12.8 vs. 68.6±11.4 kg), had higher BMI (30.0±4.2 vs. 25.4±4.0 kg/m2) and body fat (39.9±4.4 vs. 35.1±5.6 %). All strength measures were significantly lower in those below the cutoff (all P<0.05), and performances in the physical function tests were poorer (all P<0.01). They also presented significantly (P<0.02) lower QoL scores in the physical functioning (87.9±11.2 vs. 92.8±6.5), role physical (83.7±21.6 vs. 94.3±12.5), role emotional (84.8±24.3 vs. 94.4±12.4), social functioning (87.1±20.4 vs. 95.2±13.4), and general health (65.0±15.0 vs. 75.1±14.3) domains, and significantly higher total cholesterol (5.7±0.8 vs. 5.3±0.8 mmol/L), LDL-cholesterol (3.6 ± 0.8 vs. 3.2±0.6 mmol/L), total/HDL-cholesterol ratio 3.7±0.8 vs. 3.4 ± 0.8), and triglycerides (1.2±0.5 vs. 1.0±0.4 mmol/L). Absolute HGS was not significantly correlated with physical function outcomes. Conclusions: Body mass-normalized HGS is a better discriminator of physical function, QoL and cardiometabolic risk than absolute HGS, indicating its relevance in the clinical evaluation of middle-aged women.