A British study using data from 475,397 participants has shown that, on average, stronger people performed better across every test of brain functioning used. Tests looked at reaction speed, reasoning, visuospatial memory, prospective memory, and working memory (digit span). The relationship between muscular strength and brain function was consistently strong in both older and younger adults (those under 55 and those over), contradicting previous research showing it only in older adults.
The study also found that maximal handgrip was strongly correlated with both visuospatial memory and reaction time in 1,162 people with schizophrenia (prospective memory also approached statistical significance).
The finding raises the intriguing possibility that weight training could be particularly beneficial for people with mental health conditions, such as schizophrenia, major depression and bipolar disorder.
Full text available online at https://doi.org/10.1093/schbul/sby034
 . Grip Strength Is Associated With Cognitive Performance in Schizophrenia and the General Population: A UK Biobank Study of 476559 Participants. Schizophrenia Bulletin [Internet]. Submitted . Available from: https://academic.oup.com/schizophreniabulletin/advance-article/doi/10.1093/schbul/sby034/4942313