Self-Determined Motivation and Physical Activity in Chronic Obstructive Pulmonary Disease

Chronic Obstructive Pulmonary Disease (COPD) is associated with reduced physical activity, negatively affecting prognosis and quality of life. According to Self-Determination Theory (SDT), the quality of motivation plays a key role in sustaining active behavior, but evidence in COPD remains limited.

The objective of this study was to examine the associations between different types of exercise motivation and objectively measured physical activity and sedentary behavior in individuals with COPD.

This cross-sectional study included 50 community-dwelling individuals with COPD (GOLD stages 2-3; mean age 69.4 ± 7 years). Motivation was assessed using the Behavioral Regulation in Exercise Questionnaire (BREQ-3) and the Self-Determination Index (SDI). Physical activity was objectively measured with the ActiGraph GT3X accelerometer. Associations were examined using Spearman's correlations and hierarchical multiple linear regression models.

Integrated regulation was positively correlated with light physical activity (rho = 0.43, p < 0.05), total physical activity (rho = 0.40, p < 0.05), and daily step count (rho = 0.43, p < 0.05). Intrinsic motivation was positively correlated with light physical activity (rho = 0.37, p < 0.05), total physical activity (rho = 0.37, p < 0.05), and daily step count (rho = 0.35, p < 0.05). The Self-Determination Index was positively associated with light physical activity (rho = 0.28, p < 0.05) and daily step count (rho = 0.33, p < 0.05), but showed no significant association with sedentary time. In hierarchical regression analyses, higher levels of integrated regulation were independently associated with higher daily step count, with each one-unit increase associated with 687 additional steps per day. For total physical activity, integrated regulation showed a borderline independent association with the outcome after adjustment for clinical covariates (β = 0.279, p = 0.054), whereas FEV₁ (% predicted) remained independently associated with total physical activity (β = 0.304, p = 0.027). For sedentary behavior, higher self-determination was independently associated with lower sedentary time; specifically, each one-unit increase in the Self-Determination Index corresponded to approximately 13 fewer sedentary minutes per day (β = -0.327, p = 0.026).

Self-determined motivation was associated with more favorable physical activity profiles in individuals with COPD. Integrated regulation was independently associated with daily step count, while higher self-determination was associated with lower sedentary time. These findings suggest that autonomous forms of motivation may be important factors to consider when promoting active lifestyles in people with COPD.