スポーツ医学およびドーピング研究ジャーナル

Background: Daily step count was associated with various health outcomes. However, the quantitative relationship between daily step count and lung function among general population is unclear to date.

Methods: We conducted a panel study with repeated measurement of daily step counts and lung function parameters in consecutive 11 days among 16 healthy male college students in a self-controlled study design. Linear mixed-effect model was used to assess the dose-response relationship between daily step count and lung function parameters.

Results: Compared with control days, subjects in intervention days had lower daily step counts and lung function parameters. Nonlinear associations of daily step count with FEV_0.5, FEV_0.5/FVC, and FEV_1.0/FVC were observed in all observations, but become insignificant in subgroups of step count ≤ 8000 or >8000. Significant linear dose-response relationships were observed in those taking daily step counts ≤ 8000, showing that each 1000-increase in daily step was significantly associated with 36.81 ml, 20.29 ml, 1.36%, 0.48%, 1.88%, 1.38%, 2.06% and 0.76% increase in FEV_0.5, FEV_1.0, FEV_0.5/FVC, FEV_1.0/FVC, MMF%pred, FEF25%_pred, FEF50%_pred, and FEF75%_pred, respectively.

Conclusion: Increased daily step count benefits lung function among healthy male adults, though the excess benefit was limited when taking more than 8000 steps per day.