Age-associated decline in grip strength

Background: Grip strength is a well-established functional biomarker of musculoskeletal health and overall physiological resilience throughout the lifespan, making it a valuable indicator in aging research. Purpose: This study aimed to quantify the rate of change (kg/year) and percentage change (%) in grip strength across the lifespan (ages 6-79), stratified by gender and hand dominance. Study Design: Cross-sectional, observational study. Methods: Data from 13,159 participants in the National Health and Nutrition Examination Survey (NHANES) study were analyzed. Grip strength was measured using a Takei Digital Handgrip Dynamometer, with the best of three trials recorded. The rate of change (kg/year) and percentage change (%) were computed for dominant and nondominant hands by gender. Results: The dominant hand showed greater increases in childhood, peaking at age 14 in males (3.89 kg/year) and age 11 in females (2.37 kg/year). Growth slowed in young adulthood, stabilizing by ages 30-34, then declined. By midlife (50s), decline accelerated (−0.30 kg/year in males, −0.24 kg/year in females), reaching −0.41 kg/year (males) and −0.29 kg/year (females) by ages 69-79. For percentage change, males had 78.62% lower grip strength and females had 68.51% lower grip strength at age 6 compared with their peak (30s). By adolescence, the gap narrowed (−32.78% in males, −15.39% in females at age 14). Strength peaked at ages 32-33 in males and 32-35 in females. After age 35, percentage loss became progressively negative, reaching −7.76% in males and −4.49% in females by age 50, −11.57% and −14.48% by age 60, and nearly −29.23% and −29.04% by age 79. Conclusions: This study elucidates the evolving patterns of grip strength across the lifespan, contributing valuable insights into grip strength as a potential biomarker of aging.