The impact of a dairy milk recovery beverage on bacterially stimulated neutrophil function and gastrointestinal tolerance in response to hypohydration inducing exercise stress

Abstract

The study aimed to determine the impact of a dairy milk recovery beverage immediately after endurance exercise on leukocyte trafficking, neutrophil function, and gastrointestinal tolerance markers during recovery. Male runners (N = 11) completed two feeding trials in randomized order, after 2 hr of running at 70% VO2max, fluid restricted, in temperate conditions (25 °C, 43% relative humidity). Immediately postexercise, the participants received a chocolate-flavored dairy milk beverage equating to 1.2 g/kg body mass carbohydrate and 0.4 g/kg body mass protein in one trial, and water volume equivalent in another trial. Venous blood and breath samples were collected preexercise, postexercise, and during recovery to determine the leukocyte counts, plasma intestinal fatty acid binding protein, and cortisol concentrations, as well as breath H2. In addition, 1,000 μl of whole blood was incubated with 1 μg/ml Escherichia coli lipopolysaccharide for 1 hr at 37 °C to determine the stimulated plasma elastase concentration. Gastrointestinal symptoms and feeding tolerance markers were measured preexercise, every 15 min during exercise, and hourly postexercise for 3 hr. The postexercise leukocyte (mean [95% confidence interval]: 12.7 [11.6, 14.0] × 109 /L [main effect of time, MEOT]; p