Impact of single and multiple sets of resistance exercise in type 1 diabetes

To examine glycemic and glucoregulatory responses to resistance exercise (RE) sessions of different volume in type 1 diabetes (T1DM). Eight T1DM (seven males: one female; age: 38±6 years, HbA1C: 8.7±1.0%/71±11mmol/mol) attended the research facility fasted and on four separate occasions, having taken their usual basal insulin, but omitted morning rapid-acting insulin. Participants completed a 1SET (14min), 2SET (28min), 3SET (42min) RE session (eight exercises×10 repetitions) at 67±3% one-repetition-maximum followed by 60-min recovery, or a resting trial (CON). Venous blood samples were taken before and after exercise. Data (mean±SEM) were analyzed using repeated-measures analysis of variance (P≤0.05). RE did not induce hypoglycemia (BG0.05) with pre-exercise after 3SET. BGIAUC(area-under-curve) (mmol/L/60min) was greater after 1SET and 2SET vs CON (1SET 103.6±36.9 and 2SET 128.7±26.1 vs CON -24.3±15.2, P0.05). Under all trials, plasma creatine kinase levels at 24h post-exercise were similar (P>0.05) to pre-exercise. RE does not induce acute hypoglycemia or damage muscle. BG progressively rose after one and two sets of RE. However, inclusion of a third set attenuated exercise-induced hyperglycemia and returned BG to that of a non-exercise trial.