The Association of the Timing of Physical Activity with Cardiometabolic Health in Diabetes: An IMI2 SOPHIA Study

This study aimed to investigate the association of timing of the most active five hours (M5 time) with markers of cardiometabolic health in people with type 1 diabetes (T1D) and type 2 diabetes (T2D).

People with T1D or T2D were invited to participate in the study. Physical activity was measured over a 7-day period with a wrist worn accelerometer. The M5time (as a linear and circular (sin-cos) variable) and the amount of activity in these five hours (M5value) were calculated, and associations with glycaemic control, blood lipids and body composition were examined using multiple linear regression, with multiple testing controlled using false discovery rate (FDR) correction.

A total of 891 people with T1D and 1381 people with T2D were included. In people with T1D, M5time (linear) was associated with waist circumference after full adjustment (model 3) (B = -0.32, SE = 0.15, FRD p = 0.047). Similarly, in people with T1D M5 time (circular) was also significantly associated with BMI (p = 0.004) and waist circumference (p = 0.001), with amplitudes of BMI: 1.32 kg/m2 and Waist: 4.28 cm, and phases of BMI: 12:51h and Waist: 13:06h. In people with T2D, M5 time was not associated with any cardiometabolic markers after FDR correction in any adjusted models.

In people with T1D, the time of day at which people were most active was associated with some cardiometabolic markers. However, in people with T2D, there was no association with any cardiometabolic markers. Overall, our data indicates little effect of time of and physical activity at any time of day should be promoted.