The effect of carbohydrate ingestion on the interleukin-6 response to a 90-minute run time trial.
Fatigue is a predictable outcome of prolonged physical activity; yet its biological cause remains uncertain. During exercise, a polypeptide messenger molecule interleukin- 6 (IL-6) is actively produced. Previously, it has been demonstrated that administration of recombinant IL-6 (rhIL-6) impairs 10-km run performance and heightened sensation of fatigue in trained runners. Both high carbohydrate diets and carbohydrate ingestion during prolonged exercise have a blunting effect on IL-6 levels postendurance exercise. We hypothesized that carbohydrate ingestion may improve performance during a prolonged bout of exercise as a consequence of a blunted IL-6 response. Seven recreationally trained fasted runners completed two 90-min time trials under CHO supplemented and placebo conditions in a randomized order. The study was of a double-blinded, placebo-controlled, cross-over study design. Distance covered in 90 min was significantly greater following exogenous carbohydrate ingestion compared with the placebo trial (19.13+/-1.7 km and 18.29+/-1.9 km, respectively, p=.0022). While postexercise IL-6 levels were significantly lower in the CHO trial compared with the placebo trial (5.3+/-1.9 pg.mL(-1) and 6.6+/-3.0 pg.mL(-1), respectively; p=.0313), this difference was considered physiologically too small to mediate the improvement in time trial performance.
Robson-Ansley
Paula
P
School of Psychology and Sport Sciences, Northumbria University, Newcastle upon Tyne, UK.
Barwood
Martin
M
Eglin
Clare
C
Ansley
Les
L
D000284:Administration, Oral; D000328:Adult; D054874:Athletic Performance; D001628:Beverages; D015415:Biomarkers / Q000097:blood; D018592:Cross-Over Studies; D004040:Dietary Carbohydrates / Q000008:administration & dosage*; D004311:Double-Blind Method; D015536:Down-Regulation; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D018763:Muscle Fatigue / Q000187:drug effects*; D011134:Polysaccharides / Q000008:administration & dosage*; D012420:Running; D013997:Time Factors; D055815:Young Adult
D015415:Biomarkers; D004040:Dietary Carbohydrates; C508600:IL6 protein, human; D015850:Interleukin-6; D011134:Polysaccharides; C008315:maltodextrin