Temporal changes and reference values for adolescent handgrip strength in the Republic of Korea: A 9-year analysis of the KNHANES cohort.

We aimed to examine temporal changes in handgrip strength and develop reference values among adolescents (10-19 years; n = 4,867) in the Republic of Korea. A general linear model was used to explore differences in absolute and body size normalized (height and body mass) handgrip strength across survey years using data from KNHANES 2014-2022. Weighted percentiles were calculated to generate reference values. In some of the male age groups, handgrip strength was lower in 2016-2019 (-1.7 to -4.1 kg; -0.197 to -0.267 units) and higher in 2014-2015 (2.6 to 3.5 kg; 0.175 to 0.309 units), compared to 2022. In some of the female age groups, handgrip strength was lower in 2016-2019 (-1.6 to -2.6 kg; -0.123 to -0.302 units) and higher in 2014-2015 (1.4 kg; 0.178 to 0.316 units), compared to 2022. Reference values were lowest among 10-11‑year‑olds, showed progressive increases across older age groups, and differed according to sex. Overall, handgrip strength remained fairly stable over the 9-year period, even though in some of the years it was lower or higher compared to the most recent wave. However, these differences were generally small, did not occur at every survey year, and were completely absent for some of the sex and age groups. A similar pattern was observed for normalized values, although the results were not entirely consistent with absolute handgrip strength data. The provided reference values enable interpretation of absolute and body size normalized handgrip strength in Korean adolescents.