A recent study compared the impact of two different, but commonly consumed, beverages on integrative markers of exercise recovery following a 2 h high-intensity interval exercise (i.e., running 70–80% V̇O2max intervals and interspersed with plyometric jumps). 11 males and 6 females who enrolled for the study were given chocolate flavored dairy milk beverage (CM: 1.2 g carbohydrate/kg BM and 0.4 g protein/kg BM) or a carbohydrate-electrolyte beverage (CEB: isovolumetric with 0.76 g carbohydrate/kg BM) after exercise. These recovery beverages were given in three equal boluses over a 30 min period beginning 1 h post-exercise and muscle biopsies were performed at 0 h and 2 h in recovery. 

Venous blood samples, nude BM and total body water were drawn before and at 0, 2, and 4 h recovery. Gastrointestinal symptoms and breath hydrogen (H2) were checked before exercise and every 30 min during recovery. Next morning, the participants underwent a performance assessment. In recovery, breath H2 gained clinical relevance of >10 ppm after consumption of both beverages, along with a high incidence of gastrointestinal symptoms (70%), but modest severity. Blood glucose response was more prominent on CEB than CM, while Insulin response was vice versa. Escherichia coli lipopolysaccharide-stimulated neutrophil function decreased on both beverages (49%). p-GSK-3β/total-GSK-3β was more on CM than CEB; however, none of the beverages gained net muscle glycogen re-storage. Phosphorylation of mTOR was found to be more prominent on CM than CEB. Fluid retention was lower on CEB (74.3%) than CM (82.1%). Physiological and performance outcomes on the next day were similar between trials. Interconnected recovery optimization markers seem to react differently to the nutrient composition of recovery nutrition, albeit subtly and with individual variation. 

These findings explain recovery nutrition strategies to mark functionality and patency of the gastrointestinal tract as a requirement to the assimilation of recovery nutrition and restoration of immunocompetency.

Source: Russo I, Della Gatta PA, Garnham A, Porter J, Burke LM, Costa RJS. Assessing Overall Exercise Recovery Processes Using Carbohydrate and Carbohydrate-Protein Containing Recovery Beverages. Frontiers in Physiology, 2021. https://www.frontiersin.org/article/10.3389/fphys.2021.628863