Abstract

Aims
To determine the influence of different volumes of resistance exercise on circulating interleukin‐6 (IL‐6) and to explore the relationships between IL‐6 and glycaemia.

Methods
Eight participants with complication‐free Type 1 diabetes, whose mean ± sem age was 38 (6) years, mean ± sem HbA1c concentration was 71 ±11 mmol/mol (8.7 ±1.0%) and mean ± sem Type 1 diabetes duration was 15 ±13 years, attended the research facility after an overnight fast on four separate occasions, having administered their basal insulin the night before (glargine 27.5±3.1U, n=8), but omitted morning rapid‐acting insulin. Participants completed either a one‐set (14‐min), two‐set (28‐min), or three‐set (42‐min) resistance exercise trial (eight exercises × 10 repetitions) at 67±3% one‐repetition maximum followed by a 60‐min recovery, or a resting control trial. Venous blood samples were taken before and after exercise. Data were analysed using repeated‐measures anova (P≤0.05).

Results
Whereas IL‐6 levels remained similar to baseline levels after one set of resistance exercises (30 min, P=0.287; 60 min, P=0.318), IL‐6 levels were > baseline levels at 60 min post‐exercise after a two‐set exercise trial (2.94 ± 0.94 pg/ml, P=0.002) and doubled at both 30 min (4.01 ± 1.00 pg/ml, P=0.048) and 60 min (4.28 ± 1.25 pg/ml, P=0.084) post‐exercise after the three‐set resistance exercise trial. Post‐exercise blood glucose area under the curve (mmol/l/60 min) was greater after both the one‐set (P=0.025) and two‐set trials (P=0.008), than after the control trial, but similar between the three‐set trial and the control trial (P=0.240). The rise in IL‐6 from baseline to peak concentration significantly correlated inversely with blood glucose area under the curve (r=‐0.65, P=0.041).

Conclusions
Circulating IL‐6 is increased by resistance exercise in a volume‐dependent manner, and resistance exercise‐induced increases in IL‐6 correlated with reductions in post‐exercise hyperglycaemia in Type 1 diabetes, suggesting a role for IL‐6 in improving post‐resistance exercise glycaemic disturbances in Type 1 diabetes.

(Clinical Trials Registry No: ISRCTN60407046)