Previous research has shown that physical activity is good for our bodies and minds, and spending too much time sedentary (sitting) tends to do the opposite for our health.
Physical activity is increasingly being measured using accelerometry devices, which track intensity and duration of body movement. The use of accelerometers is an advance over the previously used self-report methods, which are prone to measurement error from imprecise and biased recall, and can thereby mask the true nature and magnitude of associations.
Our study examined whether prior activity patterns were associated with later health outcomes. The large sample of detailed data on accelerometer-measured physical activity in EPIC-Norfolk, along with incident disease data and a long follow-up duration made EPIC-Norfolk an ideal study for this work.
We broke the physical activity down into four different kinds of activity: Total physical activity, light physical activity, moderate-to-vigorous physical activity and total time spent per day sedentary.
What we found
After adjustment for several important lifestyle and demographic factors, we found that higher levels of total physical activity and moderate-vigorous physical activity were associated with lower incident cardiovascular disease risk
Higher levels of sedentary time were associated with higher risk of cancer and all-cause mortality while higher levels of light-intensity activity were associated with lower risk for these two outcomes.
Summary
The findings highlight that different types of activity may be of differing importance for different health outcomes when measured in more detail. The results of this study suggest that it seems to be important to be more physically active and at higher intensities to improve heart health and cardiovascular risk, whereas the time we spend sedentary and in light intensity activities seems to hold importance when it comes the risk of cancer and all-cause mortality. A consistent take-home message that comes through with all health outcomes is that ‘all activity counts’ towards reducing the risk of several important disease outcomes.
Full paper: Paddy C. Dempsey, Tessa Strain, Kay-Tee Khaw, Nicholas J. Wareham, Søren Brage, Katrien Wijndaele. Prospective Associations of Accelerometer-Measured Physical Activity and Sedentary Time With Incident Cardiovascular Disease, Cancer, and All-Cause Mortality