758. Do Short Spurts of Physical Activity Benefit Cardiovascular Health? The CARDIA Study
Commentary by Sophie Cassidy, Clinical exercise physiologist, Newcastle University, UK.
Current American, as well as some international, guidelines suggest ≥150mins/week of moderate-to-vigorous physical activity (MVPA) occurring in bouts of ≥10mins, should be performed for optimal health benefits. However, much of our habitual everyday activity such as climbing stairs, occurs in shorter spurts of <10mins throughout the day. The aim of this study was to investigate whether these shorter spurts of activity confer health benefits.
2026 individuals (aged 45years, 58% female) from the CARDIA cohort wore an actigraph accelerometer around their waist for 7 consecutive days at baseline to capture objective physical activity. MVPA lasting <10 mins was defined as ‘short spurts’. Blood pressure and body mass index were measured at baseline and at 5-yr follow up. Of those who were healthy at baseline, 14.8% and 12.1% developed hypertension and obesity respectively. Those in the highest tertile of short spurts were 31% less likely to develop hypertension than those in the lowest tertile. In contrast, short spurts did not reduce obesity risk, whereas MVPA lasting ≥10mins did reduce obesity risk.
These results, along with the accumulating evidence surrounding high intensity interval training (HIIT), indicate that shorter periods of activity provides sufficient stimulus for cardiovascular health benefits. Clinical trials have demonstrated the benefit of HIIT to improve cardiac health, which is a strong predictor of mortality. Despite these clear cardiac benefits, shorter periods of activity are unlikely to result in the negative energy balance required to induce weight loss. Short spurts of physical activity should be encouraged to improve cardiovascular health, but its benefits for weight loss should not be overstated.
Source: Medicine & Science in Sports & Exercise, 47: 2353-8. Access to this article may depend on your institutional rights: Access the whole article.