Researchers have identified grip strength as a reliable marker of overall health, with studies linking it to longevity and a range of conditions including type 2 diabetes and depression. A simple squeeze test using a tennis ball can provide a useful indication of muscle strength.
Joshua Davidson, a strength and conditioning researcher at the University of Derby, recommends squeezing a tennis ball for as long as possible. Maintaining a maximal squeeze for 15-30 seconds is considered a good standard. While a weak grip alone may not significantly affect daily life, it serves as a proxy for overall musculoskeletal health.
A major study of nearly 140,000 adults found grip strength to be a better predictor of premature death than blood pressure. Another study tracking volunteers from 1965-1968 showed that those who became centenarians were 2.5 times more likely to have had grip strength in the highest third.
Darryl Leong of McMaster University explains that grip strength reflects nutrition, physical activity, and illness. Scores below 25.5 kg for men and 18 kg for women indicate a heightened risk of sarcopenia, the progressive loss of muscle mass linked to falls and fractures.
Muscle also plays a key role in metabolism, acting as a reservoir for blood glucose. Weak grip strength may signal a greater risk of metabolic dysfunction, including type 2 diabetes, lower bone density, and cognitive impairment.
