Objectively assessed physical activity, fitness and subjective wellbeing

Background: The existing evidence for a cross-sectional association between physical activity and subjective wellbeing is inconsistent, mainly because of the reliance on self reported physical activity, which might have conceptual overlap with subjective health. Purpose: To examine associations of objectively assessed physical activity and cardiorespiratory fitness with subjective wellbeing. Methods: A sub-sample of participants (921 men and women, mean age 44.6 ± 15.0 yrs, 46.4% men) from the 2008 Health Survey for England completed objective measures of physical activity (Actigraph) and an 8 min sub-maximal step test to estimate levels of cardiorespiratory fitness. The General Health Questionnaire and self-rated health was used as indicators of subjective wellbeing. Results: The recorded levels of moderate to vigorous physical activity (MVPA) were higher in participants reporting very good health (adjusted mean difference = 6.7, 95% CI, 1.1-12.4 min/d, p = 0.019) compared with participants reporting fair-poor health after adjustment for various confounders and fitness level. Neither physical fitness, objectively assessed sedentary time or light activity was related to self-rated health. There was also no association between objectively measured physical activity and fitness with psychological health, despite a robust association with self reported MVPA in the overall sample. Conclusions: Objectively assessed MVPA is independently associated with self-rated health. Self reported, but not objectively assessed MVPA, was associated with psychological health. The null findings with regards to psychological health might partly reflect selection biases associated with the healthy nature of this sub-sample of participants.