Association of knee-extension strength with instrumental activities of daily living in community-dwelling older adults

Aim The purpose of the present study was to investigate the relationship between knee‐extension (KE) strength and instrumental activities of daily living (IADL), and to examine the risk of IADL disability in relation to KE strength in community‐dwelling older adults. Methods The participants were 1235 community‐dwelling older adults (261 men and 974 women) in Tokyo who underwent a comprehensive health survey in 2009. The health survey included measurement of KE strength and a questionnaire on the Tokyo Metropolitan Institute of Gerontology (TMIG)‐IADL. Pearson product‐moment correlation coefficients and partial correlation coefficients were calculated separately for each sex for four parameters representing quadriceps muscle strength and TMIG‐IADL. Pearson's χ2‐test of independence and the Cochran–Armitage test of trend were also carried out to determine the relationship between KE strength and IADL disability. Results In women, all correlations between the quadriceps muscle strength parameters and the TMIG‐IADL score were statistically significant (P