This study aimed to reveal the status of physical fitness (PF) levels and determine whether hand grip strength (HGS) could be used to estimate other PF parameters in older adults from large population data. A total of 46,269 participants aged ≥ 65 years who participated in the 2019 National Fitness Award Project in South Korea were included in the analysis. Of the participants, 6.8% had the highest level of overall physical fitness, while 48.9% had the lowest level. The proportion of overall PF levels differed significantly according to age groups. Significant associations between HGS and other PF parameters (30-s chair stand test, 2-min or 6-min walk test, sit-and-reach test, 3-m backwards walk test, and Figure-of-8 walk test) were noted and the group with low HGS (< 28 kg for men and < 18 kg for women) had significantly higher odds of having the lowest level of overall PF (odds ratio: 5.232 in men and 6.351 in women), after adjusting for age and body mass index. HGS could estimate muscular strength and endurance, aerobic fitness, flexibility, balance skills, and coordination skills, as well as overall PF level in older adults, and could be used as a substitute test for their PF level in limited situations.

As each polyclinic differed in location, they addressed different populations of athletes; hence, the study provides insights into the injury trends and different physiotherapy treatments.