Background: For optimal health benefits, moderate- to vigorous-intensity physical activity (MVPA) is recommended in sustained bouts lasting ≥10 min. However, short spurts of MVPA lasting <10 min are more common in everyday life. It is unclear whether short spurts of MVPA further protect against the development of hypertension and obesity in middle-age adults beyond bouted MVPA.
Methods: Objectively measured physical activity was collected in the Coronary Artery Risk Development in Young Adults study at the 20-yr (2005-2006) examination, and blood pressure and BMI were collected at the 20- and 25-yr (2010-2011) examinations. Time spent in MVPA was classified as either bouted MVPA, i.e., ≥10 continuous minutes or short spurts of MVPA, i.e., <10 continuous minutes. To examine the association of short spurts of MVPA with incident hypertension and obesity over 5 yr, we calculated risk ratios adjusted for bouted MVPA and potential confounders.
Results: Among 1531 and 1251 participants without hypertension and obesity, respectively, at year 20 (age, 45.2 ± 3.6 yr; 57.3% women; body mass index, 29.0 ± 7.0 kg·m(-2)), 14.8% and 12.1% developed hypertension and obesity by year 25. Study participants in the highest tertile of short spurts of MVPA were 31% less likely to develop hypertension 5 yr later (risk ratio = 0.69 (0.49-0.96)) compared with those in the lowest tertile. There was no statistically significant association of short spurts of MVPA with incident obesity.
Conclusions: These findings support the notion that accumulating short spurts of MVPA protects against the development of hypertension but not obesity in middle-age adults.