Exercise modality and subsequent musculoskeletal medical expenditures among middle-aged and older adults: A population-based longitudinal study.

Background/objective: Musculoskeletal disorders (MSDs) contribute substantially to pain, disability, and health care spending in aging populations. Although physical activity has been associated with lower health care costs, less is known about whether medical expenditures differ by exercise modality. This study examined whether musculoskeletal medical expenditures differed between non-exercisers, unsupervised exercisers, and supervised exercisers among middle-aged and older adults. Methods: Using Korea Health Panel data from 2019 to 2023, we examined the association between exercise modality assessed in a given year and musculoskeletal medical expenditures measured in the following year among adults aged ≥40 years. Exercise modality was classified as non-exercise, unsupervised exercise, or supervised exercise with paid professional instruction. Medical expenditures were modeled using generalized estimating equations with a gamma distribution and log link. Adjusted expenditure ratios (aERs) were estimated using pairwise comparisons, adjusting for sociodemographic characteristics, chronic disease status, and previous-year medical expenditures. Analyses were stratified by age group, with additional sex-stratified analyses conducted within age groups. Results: Among adults aged 40-59 years, musculoskeletal medical expenditures did not clearly differ by exercise modality. Among adults aged ≥60 years, non-exercisers had higher musculoskeletal medical expenditures than unsupervised exercisers (aER 1.17, 95% CI 1.06-1.30; P = .003). However, differences involving supervised exercise were not clearly observed, including supervised versus unsupervised exercise (aER 0.92, 95% CI 0.62-1.36; P = .67) and supervised exercise versus non-exercise (aER 0.78, 95% CI 0.53-1.16; P = .23). In additional sex-stratified analyses, the difference between non-exercisers and unsupervised exercisers appeared more evident among men aged ≥60 years. Conclusion: Among adults aged ≥60 years, non-exercisers had higher subsequent musculoskeletal medical expenditures than unsupervised exercisers, whereas supervised exercise was not clearly associated with additional expenditure differences beyond unsupervised exercise. These findings suggest that regular exercise participation may be relevant to musculoskeletal health care spending in older adults, while the incremental economic value of professional supervision requires further investigation.