Dose-response association of an accelerometer-measured physical activity with all-cause mortality and cardiovascular disease incidence: Prospective cohort with 76,074 participants.

Objective: To investigate the prospective dose-response association of accelerometer-measured moderate-to-vigorous physical activity (PA;MVPA) with all-cause mortality and cardiovascular disease (CVD) incidence.

Methods: This prospective cohort of 76,074 participants from the UK Biobank study contained one week of individual accelerometer-based PA data collected between June 1, 2013 and December 23, 2015. Using restricted cubic splines to allow for potential non-linearity, we examined dose-response associations of MVPA with all-cause mortality and incident CVD, respectively.

Results: The median follow-up time was 8.0 years (IQR 7.5-8.5). The dose-response association of MVPA with all-cause mortality and CVD showed a similar L-shaped association, with significant risk reductions already from 10 min of MVPA per week for all-cause mortality (hazard ratio [HR], 0.98 [95 % CI,0.98-0.99]) and 15 min per week for CVD incidence (HR, 0.99 [95 % CI,0.98-0.99]). Doing more MVPA was associated with further risk reduction, but beyond around 500 min per week the benefits levelled off at HR's around 0.6 to 0.7. The highest additional benefit of adding more minutes per week for all-cause mortality and CVD incidence were observed between 100 and 250 weekly minutes of MVPA. From this point forward, the mean risk reduction rates decreased and were close to 0 beyond 500 weekly minutes.

Conclusions: Significant, but small, risk reductions in all-cause mortality and CVD incidence can be achieved with as little as 10 and 15 min of MVPA per week, respectively. However, public health organizations should promote the attainment of 250 min of MVPA per week (with 100 min as a possible first target for inactive individuals), as these thresholds are associated with the greatest efficiency. Beyond that, less pronounced risk reductions can be achieved by accumulating additional MVPA, with hardly any additional benefits beyond 500 weekly minutes.