According to recent findings from a study published in the Journal of Diabetes Care, it has been observed that the timing of bout-related moderate- to vigorous-intensity physical activity (MVPA) is associated with cardiorespiratory fitness and cardiovascular risk in men with type 2 diabetes.
Studies from the literature have revealed that moderate- to vigorous-intensity physical activity (MVPA) improves cardiovascular health, however, there are very few studies which have examined the MVPA timing.
Therefore, Jingyi Qian and colleagues conducted this present study to examine the associations of timing of bout-related MVPA with cardiorespiratory fitness and cardiovascular risk in adults with type 2 diabetes.
The authors analyzed baseline 7-day hip-worn accelerometry data from Look AHEAD participants (n = 2,153, 57% women) to identify bout-related MVPA (≥3 METs/min for ≥10 min). Cardiorespiratory fitness was assessed by maximal graded exercise test.
Participants were categorized into six groups on the basis of the time of day with the majority of bout-related MVPA (METs × min): ≥50% of bout-related MVPA during the same time window (morning, midday, afternoon, or evening), <50% bout-related MVPA in any time category (mixed; the reference group), and ≤1 day with bout-related MVPA per week (inactive).
The study revealed the following interesting results-
a. Cardiorespiratory fitness was highly associated with timing of bout-related MVPA (P = 0.0005), independent of weekly bout-related MVPA volume and intensity. Importantly, this association varied by sex (P = 0.02).
b. In men, the midday group had the lowest fitness (β = −0.46 [95% CI −0.87, −0.06]), while the mixed group in women was the least fit. Framingham risk score (FRS) was associated with timing of bout-related MVPA (P = 0.02), which also differed by sex (P = 0.0007).
c. The male morning group had the highest 4-year FRS (2.18% [0.70, 3.65]), but no association was observed in women.
Hence, it was concluded that "Timing of bout-related MVPA is associated with cardiorespiratory fitness and cardiovascular risk in men with type 2 diabetes, independent of bout-related MVPA volume and intensity. Prospective studies are needed to determine the impacts of MVPA timing on cardiovascular health."