News & Insights 26 August 2020

Is activity intensity important in reducing health risk?

New research from the Epidemiology Unit at the University of Cambridge, published in the peer-reviewed medical journal Nature Medicine, considers the use of physical activity for personalised prevention of future health risk.

Whilst physical activity of any kind is beneficial for one’s health profile, this large-scale study enhanced our knowledge of the role of intensity in physical activity and concluded that higher intensities may elicit additional health benefits.

Low intensity and incidental movements that accumulate throughout the day have previously been difficult to accurately capture and measure. However, the rise of wearable technologies has enabled researchers to more readily detect these smaller movements. Wearable devices that monitor physical activity are currently increasing in popularity, with projections that their usage will increase more than five-fold in the next 5 years. Dr Søren Brage, a senior author on the paper, highlighted their utility in capturing the physical activity profiles of large cohorts, enabling researchers to “disentangle the roles of volume and intensity of activity in influencing future health”.

Within the study, activity was expressed as physical activity energy expenditure (PAEE) and researchers determined the percentage of this that could be attributed to moderate and vigorous activity (MVPA). Whilst accumulating a PAEE of 20kJ/kg/day was associated with a 37% reduction in risk of all-cause mortality, a PAEE of 30kJ/kg/day was associated with a 69% reduction of risk compared with a PAEE of 15kJ/kg/day. The percentage of MVPA was a similarly significant determining factor for risk. Accumulating 20% of PAEE from MVPA reduced risk of all-cause mortality by 56% and a 60% proportion was associated with a 91% lower risk compared with 5%. Different combinations of total PAEE and proportion from MVPA were associated with different reductions in risk. This knowledge affords individuals with an informed choice, enabling them to trial varying combinations of both total physical activity and the intensities of these activities, to amass different risk reductions.

“Our results show that doing more activity of any intensity is beneficial, but that expending those calories in more intense activity is better still. By gradually building up the intensity of physical activity we do each day, we can improve our future health,” said Dr Tessa Strain, lead author of the paper.

Whilst the underlying intensity contributions of each individual varied drastically as a result of the large scale of the study, with nearly 100,000 participants being enrolled from UK Biobank, the findings remained consistent. This was despite many participants having a range of pre-existing conditions including diabetes, heart disease and cancers, many which may limit physical activity levels. Pre-existing conditions therefore do not need to act as a barrier to an active lifestyle, or limit your ability to maintain a positive health profile.

At KiActiv® we aim to empower individuals to understand the value of their everyday movement and establish what activity is the right fit for them as an individual. Whilst the benefits of higher intensity activity are clear, it is not a necessity for good health. The results simultaneously highlight that activity volumes accumulated almost exclusively through light activity can still reduce mortality rate by 50%, supporting our personalised philosophy that multiple pathways exist for individuals to follow to maintain good health – every individual should choose the path that works best for them!

The KiActiv® Team