Milk Consumption Following Acute High-Intensity Exercise Supports Bone Status Indices in Young, Healthy Adults: A Randomized Crossover Study.

Exercise and nutrition, particularly dairy, are lifestyle factors that influence bone health, however, there is limited evidence on how wholefood dairy consumption affects acute post-exercise bone status indicator (BSI) responses. Additionally, products like milk and Greek yogurt (GY) may elicit distinct BSI responses due to their differing dairy matrices. Thus, the objective of this study was to determine whether the consumption of either MILK, GY, carbohydrate (CHO) or WATER, differentially modulates BSIs post-exercise. Using a randomized crossover design, twenty participants (naïve to resistance training; 8/12 male/female; age: 22.7±4.0 years; body mass index: 22.0±2.3 kg/m2) underwent an acute, multimodal exercise session consisting of plyometrics, resistance exercises and high-intensity interval cycling, followed by post-exercise supplementation. Supplements were provided immediately, 1h and 12h post-exercise. Blood samples were collected pre-exercise, immediately, 1h, 4h and 24h post-exercise. There were trial*time interactions for procollagen type-1 N-terminal propeptide (P1NP; p<0.001), C-terminal telopeptide of type-1 collagen (p<0.001), parathyroid hormone (p=0.010), receptor activator of nuclear factor kappa-B ligand (RANKL; p=0.010) and OPG:RANKL ratio (p=0.047). P1NP had a trial*sex interaction (p=0.023) and total osteocalcin had a main sex effect (p=0.020). Thus, the main findings were higher P1NP with MILK vs. WATER at 24h post-exercise (p=0.039), and lower RANKL with MILK vs. all trials at 24h post-exercise (p<0.050). These data suggest that milk consumption produced more pronounced changes in circulating BSIs vs. CHO, GY, or WATER. By effectively managing the acute post-exercise response, milk may serve as a strategic nutritional intervention to support bone remodeling and structural adaptations over time.