Pre-sleep Protein Supplementation Does Not Improve Recovery From Load Carriage in British Army Recruits

British Army basic training (BT) is physically demanding with new recruits completing multiple bouts of physical activity each day with limited recovery. Load carriage is one of the most physically demanding BT activities and has been shown to induce acute exercise-induced muscle damage (EIMD) and impair muscle function. Protein supplementation can accelerate muscle recovery by attenuating EIMD and muscle function loss. This study investigated the impact of an additional daily bolus of protein prior to sleep throughout training on acute muscle recovery following a load carriage test in United Kingdom (UK) British Army recruits. A mixed group (men/women) over over 120 new recruits were randomised to dietary control (CON), carbohydrate placebo (PLA), moderate (20g; MOD) or high (60g; HIGH) protein supplementation. Muscle function (maximal jump height), perceived muscle soreness and urinary markers of muscle damage were assessed before (PRE), immediately post (POST), 24-hours post (24h-POST) and 40-hours post (40h-POST) a load carriage test. The underlying aim of this study was to assess whether additional protein intake could attenuate aspects of muscle damage from an acute load carriage test including muscle function, muscle soreness and biomarkers of muscle damage during short term recovery.