Simulated games activity vs continuous running exercise: A novel comparison of the glycemic and metabolic responses in T1DM patients

To compare the glycemic and metabolic responses to simulated intermittent games activity and continuous running exercise in type 1 diabetes. Nine patients (seven male, two female; 35 +/- 4 years; HbA1c 8.1 +/- 0.2%/65 +/- 2mmol/mol) treated on a basal-bolus regimen completed two main trials, a continuous treadmill run (CON) or an intermittent running protocol (INT). Patients arrived to the laboratory fasted at approximate to 08:00h, replicating their usual pre-exercise meal and administering a 50% reduced dose of rapid-acting insulin before exercising. Blood glucose (BG), K+, Na++, pH, triglycerides, serum cortisol and NEFA were measured at baseline and for 60min post-exercise. Interstitial glucose was measured for a further 23h under free-living conditions. Following exercise, BG declined under both conditions but was less under INT (INT -1.1 +/- 1.4 vs CON -5.3 +/- 0.4mmol/L, P=0.037), meaning more patients experienced hypoglycemia (BG3.5mmol/L; CONn=3 vs INTn=2) but less hyperglycemia (BG10.9mmol/L; CONn=0 vs INTn=6) under CON. Blood lactate was significantly greater, and pH lower, with a temporal delay in K+ under INT (P<0.05). No conditional differences were observed in other measures during this time, or in interstitial glucose concentrations during the remaining 23h after exercise. Simulated games activity carries a lower risk of early, but not late-onset hypoglycemia than continuous running exercise in type 1 diabetes.