Bovine colostrum, training status, and gastrointestinal permeability during exercise in the heat: a placebo-controlled double-blind study.

摘要: Heat stress can increase gastrointestinal permeability, allowing ingress of gram-negative bacterial fragments and thus potentially inflammation ultimately endotoxemia. Permeability may rise with intense exercise, yet some data indicate that endotoxemia be mitigated bovine colostrum supplementation. Using a double-blind, randomised, placebo-controlled crossover study, we tested whether (COL; 1.7 g·kg−1·day−1 for 7 days) would attenuate physiological strain aid exercise capacity in the heat, especially untrained individuals. Seven trained men (T; peak oxygen uptake 64 ± 4 mL·kg−1·min−1) 8 (UT, 46 exercised 90 min 30 °C (50 % relative humidity) after COL or placebo (corn flour). Exercise consisted 15-min cycling at 50 heart rate reserve (HRR) before 60 running (30 80 HRR then 30-min distance trial). Heart rate, blood pressure (Finometer), esophageal, skin temperatures were recorded continuously. Gastrointestinal permeability was assessed from urine (double-sugar model, using high-performance liquid chroma- tography) (intestinal fatty acid-binding protein, I-FABP). The T group ran 2.4 km (35%) further than UT trial, I-FABP increased more group, but performance outcomes unaffected by supplementation, irrespective fitness. Circulating pro- anti-inflammatory cytokine concentrations higher following not modulated fitness COL. Despite substantial thermal cardiovascular incurred environmental conditions which exertional occur, supplementation had no observable benefit on physiology either highly endurance athletes