Interrupting sitting acutely attenuates cardiometabolic risk markers in South Asian adults living with overweight and obesity

Purpose: This study examined the acute effects of interrupting sitting with light-intensity walking on postprandial cardiometabolic risk markers in South Asian adults. Methods: South Asians with overweight/obesity (n=19; body mass index [BMI] >23 kg·m-2) and normal-weight (n=8; BMI 18.0-22.9 kg·m-2) aged 48.8 ± 5.6 years completed two, 5-h conditions: (1) prolonged sitting (SIT), and (2) interrupted sitting with 5-min bouts of light-intensity walking every 30-min (INT-SIT). Blood samples and resting expired air samples were collected throughout each condition. Statistical analyses were completed using linear mixed models. Results: In participants with overweight/obesity, postprandial glucose, triglycerides (TAG) and metabolic load index (MLI) over time were lower, whereas resting substrate utilisation and resting energy expenditure (REE) were higher, in INT-SIT than SIT (all p≤0.05). Compared with SIT (0.18 [95% CI 0.13, 0.22] kcal.min-1), INT-SIT (0.23 [95% CI 0.18, 0.27] kcal.min-1) increased postprandial REE iAUC in participants with overweight/obesity (p=0.04, d=0.51). Postprandial TAG concentrations over time were lower in INT-SIT versus SIT (p=0.01, d=30) in normal-weight participants, with no differences in any other outcomes for this sample group. Conclusion: These findings suggest that interrupting sitting with 5-min bouts of light walking every 30-min acutely attenuates cardiometabolic risk markers among South Asians living with overweight/obesity, whereas limited effects may be seen in individuals with normal-weight.