Physical activity and sedentary behaviour in relation to body composition, estimated insulin sensitivity and arterial stiffness in adults with type 1 diabetes

Aims

To examine the association of daily PA levels and sedentary behaviour with body composition, estimated insulin sensitivity, and arterial stiffness in adults with type 1 diabetes (T1D).

Methods

Cross-sectional study in adults with T1D (n = 54). PA levels (daily steps, and time in moderate-to-vigorous intensity PA (MVPA)) and sedentary behaviour were measured using accelerometry for 7 days (McRoberts® DynaPort MoveMonitor). Cardiopulmonary exercise test for VO_2max. Anthropometrics were collected, and body composition (total and % of fat mass (FM_tot, FM_%), total and % of lean mass (LM_tot, LM_%), and estimated visceral adipose tissue (VAT)) volume was assessed with dual energy X-ray-absorptiometry (DXA). Estimates of insulin sensitivity were determined (estimated glucose disposal rate (eGDR) and total daily insulin dose). Arterial stiffness was assessed with carotid-femoral pulse wave velocity (cf-PWV (m/s); SphygmoCor®).

Results

Lower 10-years HbA1_c associated moderately with all PA measures. Favourable moderate associations were also found between PA measures and BMI, waist, VAT but not FM and LM. PA measures were favourably associated with a lower total daily insulin dose and higher eGDR. All PA parameters associated moderately with cf-PWV however not independent from traditional risk factors. VO_2max was inversely associated with cf-PWV independent of age, T1D duration and 24-hour mean blood pressure.

Conclusions

Higher levels of PA, lower sedentary behaviour and greater exercise capacity are favourably associated with long-term glycaemic control, body composition, insulin dosage, estimated insulin sensitivity and arterial stiffness in adults with T1D. Therefore, regular PA and limiting sedentary time should be encouraged to improve metabolic and cardiovascular health in this population. Future longitudinal studies should explore mutual interactions and synergistic effects of PA on these outcomes.