Abstract
This study aimed to determine the effects of flavored dairy milk based recovery beverages of different nutrition compositions on markers of gastrointestinal and immune status, and subsequent recovery optimisation markers. After completing 2 h high intensity interval running, participants (n = 9) consumed a whole food dairy milk recovery beverage (CM, 1.2 g/kg body mass (BM) carbohydrate and 0.4 g/kg BM protein) or a dairy milk based supplement beverage (MBSB, 2.2 g/kg BM carbohydrate and 0.8 g/kg BM protein) in a randomized crossover design. Venous blood samples, body mass, body water, and breath samples were collected, and gastrointestinal symptoms (GIS) were measured, pre- and post-exercise, and during recovery. Muscle biopsies were performed at 0 and 2 h of recovery. The following morning, participants returned to the laboratory to assess performance outcomes. In the recovery period, carbohydrate malabsorption (breath H2 peak: 49 vs. 24 ppm) occurred on MBSB compared to CM, with a trend toward greater gut discomfort. No difference in gastrointestinal integrity (i.e., I-FABP and sCD14) or immune response (i.e., circulating leukocyte trafficking, bacterially-stimulated neutrophil degranulation, and systemic inflammatory profile) markers were observed between CM and MBSB. Neither trial achieved a positive rate of muscle glycogen resynthesis [−25.8 (35.5) mmol/kg dw/h]. Both trials increased phosphorylation of intramuscular signaling proteins. Greater fluid retention (total body water: 86.9 vs. 81.9%) occurred on MBSB compared to CM. Performance outcomes did not differ between trials. The greater nutrient composition of MBSB induced greater gastrointestinal functional disturbance, did not prevent the post-exercise reduction in neutrophil function, and did not support greater overall acute recovery.
Highlights
Sports focused food and supplement products are commonly used by athletes within elite and recreational level endurance sporting communities [1]
A MEOTime occurred for plasma cortisol concentrations, such that values were significantly lower 4 h into recovery compared to the beginning of the recovery period (P < 0.05), associated with normal daily circadian variation (Table 1)
A trial∗time interaction was observed for breath H2, with significantly greater concentrations observed on milk based supplement beverage (MBSB) at 3.5 h into recovery (P < 0.05; Figure 2A)
Summary
Sports focused food and supplement products are commonly used by athletes within elite and recreational level endurance sporting communities [1]. According to current exercise recovery nutrition guidelines and recommendations, the immediate post-exercise intake of 1.0–1.2 g/kg body mass (BM) of carbohydrate and 0.2–0.4 g/kg BM of protein will support muscle glycogen resynthesis, muscle protein synthesis. Fluid intake equivalent to 125% to 150% of the exerciseinduced BM loss is recommended for restoration of hydration status to pre-exercise levels, with sodium-containing fluids proposed to drive thirst and promote extracellular fluid retention [12] In line with these recommendations, flavored dairy milk beverages contain carbohydrate and protein in an approximate ratio of 3 to 4:1, and a naturally high sodium content (50–100 mg/100 ml) [13]. This review did not distinguish the nutritional composition (i.e., nutrient quantity and quality) of beverages, nor differentiate outcomes between the types of dairy products (e.g., dairy milk, dairy based sports beverages, and other variants); and the gastrointestinal tolerance (e.g., regulation of nutrient bioavailability) in response to gastrointestinal perturbing exercise (i.e., exercise-induced gastrointestinal syndrome) [10, 14]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
