Stronger women may be less likely to have depression

A genetic analysis of more than 341,000 UK Biobank participants found higher grip strength was associated with a lower risk of depression, and the link appeared stronger in women.

New research reports a link between greater muscle strength and lower risk of depression, with clearer associations in women than men. The study used genetic analyses to explore whether predispositions to higher strength or cardiorespiratory fitness relate to depression outcomes. Researchers measured grip strength as a proxy for overall muscle strength and compared that with genetic markers for cardiorespiratory fitness and depression-related records and questionnaire responses. The analysis drew on data from the UK Biobank and applied Mendelian randomization to reduce confounding. Key findings: - The study analyzed data from over 341,000 adults aged 37 to 73 drawn from the UK Biobank. - Higher grip strength (measured as grip per kilogram of body weight) was associated with a lower overall risk of depression; the study estimated a 14 percent lower risk per 0.1 kilogram increase in grip strength per kilogram of body weight. - Higher grip strength was also linked to lower risk of specific depressive symptoms, including reduced ability to experience pleasure, changes in appetite, depressed mood, extreme fatigue, and trouble concentrating. - The association between grip strength and some symptoms was stronger in women; the study reported larger percentage reductions for anhedonia, depressed mood, and concentration problems in women compared with men. - The researchers did not find clear evidence that genetic markers for cardiorespiratory fitness were linked to lower depression risk in this analysis. Summary: The study suggests a genetic tendency toward greater muscle strength is associated with lower depression risk and with fewer related symptoms, with more pronounced associations reported in women. Questions remain about underlying mechanisms and whether social or behavioral factors contribute, and further research was noted as needed; Undetermined at this time.