Acute effects of Greek yogurt consumption on bone status indices following high-intensity interval exercise in premenopausal females with obesity: a secondary analysis from a randomized crossover trial.

Chronic inflammation associated with excess adiposity can compromise bone microstructure, increasing fragility, and fracture risk. Thus, developing strategies to improve bone health in adults with obesity (OB) is critical, particularly in premenopausal females, to protect bone before menopause. While acute exercise transiently increases bone resorption, the first step in bone turnover, dairy products with bone-supporting nutrients may attenuate this response. This secondary analysis assessed the effects of post-exercise Greek yogurt (GY) consumption versus a carbohydrate pudding (CP) on bone status indicator responses in premenopausal females with OB. Using a randomized crossover design, 20 participants (age: 36 ± 5 years; BMI: 38.7 ± 7.6 kg/m2) completed high-intensity interval exercise (HIIE; 10 × 1 min cycling intervals at ≥90% HRmax) followed by consumption of GY (247 kcal, 14 g carbohydrate, 32 g protein, 350 mg calcium) or isoenergetic CP (247 kcal, 62 g carbohydrate, 0 g protein, 0 mg calcium). Trials were separated by 4 weeks. Blood samples were collected pre-exercise (fasted), immediately post-exercise, 1 and 3 h postprandially, and 24 h post-exercise. Significant time × trial interactions were observed whereby osteoprotegerin (OPG) and osteocalcin (OC) were higher at 1 h (p < 0.001) and 3 h (p = 0.03) postprandially, respectively, and parathyroid hormone (PTH) was lower at both 1 h (p < 0.001) and 3 h postprandially (p = 0.001) in GY versus CP. Net incremental area under the curve analysis also revealed a significant elevation in PTH across the CP trial compared to GY. Therefore, GY consumption following HIIE may support a more favourable bone turnover response by attenuating resorption (PTH), maintaining bone formation (OC), and supporting anti-resorptive responses (OPG) compared with CP during the 1-3 h postprandial period in premenopausal females with OB. Trial registration number: NCT05876260.