Associations Between Changes In Plasma Proteins And Body Composition Traits In Response To Endurance Training

Although exercise training is known to improve body composition, the molecular biomarkers and mechanisms related to these changes have not been fully elucidated. PURPOSE: The purpose of this study was to examine the associations between change in plasma proteins and change in body composition traits in response to endurance training. METHODS: Measurements were taken before and after 20 weeks of standardized, endurance training in Black and White adults of the HERITAGE Family Study (n = 652). Over 5,000 plasma proteins were measured using an aptamer-affinity based platform (SomaScan). Underwater weighing, CT scans, and anthropometric measurements were used to derive the 11 body composition traits included in this study: BMI, body surface area, fat mass, fat free mass , %fat, waist circumference, waist-to-hip ratio (WHR), body weight, and abdominal visceral, subcutaneous, and total fat. Linear mixed models were used to test the association between change in plasma proteins and change in each body composition trait adjusted for age, sex, race, baseline BMI, and baseline trait value with family membership as a random variable. Significance was set to FDR < 0.05. RESULTS: On average, subjects were 35% Black, 56% female, 35 years old, and overweight at baseline (mean BMI 26.4 (SD 5.3) kg/m2), with %fat of 27.5 (10.4). All 11 traits significantly improved in response to training. Significant associations between changes in proteins and body composition were found for all traits except WHR, with 57 unique proteins identified. Leptin was the top association (range: 0.023 < FDR p-value<4.2x10-12) for all 9 body composition traits it associated with (Table 1). CONCLUSIONS: Although dozens of proteins were associated with changes in body composition traits, 6 proteins were associated with ≥8 traits. Globally, these proteins are involved in pathways such as adipogenesis, energy balance, and cell growth, which may potentially influence body composition and fat distribution traits.