Exercise snacks performed in real-world settings reduce postprandial hyperglycaemia and glycaemic variability in individuals living with type 2 diabetes: a randomised crossover study

AIMS/HYPOTHESIS: Using a randomised, crossover design, we investigated whether exercise snacks could improve indices of glucose regulation assessed by continuous glucose monitoring, compared with an equivalent no-exercise control period in people living with non-insulin-treated type 2 diabetes. METHODS: approximately 48 mmol/mol [6.6%]) completed two experimental conditions in a randomised, counterbalanced order in the real world under a standardised diet. During the exercise snacks condition (ES), participants completed four 1 min bouts of vigorous bodyweight exercise on two consecutive days, guided by instructional videos sent via email. The control condition (CON) involved two consecutive days of no exercise. Participants wore a continuous glucose monitor and a Fitbit watch to record glycaemic responses and heart rate, respectively. The primary outcome was mean glucose during each 48 h condition. Secondary outcomes included 2 h postprandial glucose responses after standardised meals and markers of glycaemic variability. RESULTS: The difference in mean glucose between ES and CON did not reach statistical significance (between-condition difference -0.2 mmol/l; 95% CI -0.4, 0.0; p=0.07). However, small but statistically significant improvements in standard deviation (-0.1 mmol/l; 95% CI -0.2, -0.1; p<0.001), coefficient of variation (-1%; 95% CI -2, 0; p=0.007), mean amplitude of glycaemic excursions (-0.3 mmol/l; 95% CI -0.5, 0.0; p=0.04) and time in tight range (3%; 95% CI 0, 6; p=0.04) were seen under the ES condition compared with CON. The 2 h postprandial glucose average, peak, area under the curve and incremental area under the curve were also significantly lower after breakfast and dinner during the ES condition compared with CON (all p<0.05). CONCLUSIONS/INTERPRETATION: Bodyweight exercise snacks totalling 4 min of vigorous activity per day led to small, yet statistically significant improvements in indices of glycaemic variability and postprandial hyperglycaemia in insufficiently active individuals living with well-controlled type 2 diabetes. Trial registration ClinicalTrials.gov NCT06382246.