Methods: We included consecutive CR patients that underwent DXA before and after CR between the years 2014 to 2018. Clinical and DXA information were extracted from the medical record. Predictors of fat percentage (BF%) and BF loss (defined as any reduction in BF% and fat mass (kg) after CR) and muscle gain (defined as any increase in lean muscle mass after CR) were assessed with logistic regression.
Results: Among 288 patients (71% male), mean±SD age was 64.4±13.8 years, and 33(IQR 14-36) CR sessions were completed. A total of 189 (65%) reduced BF%, mean BF% change was -2.1±1.51% and 1.20±1.25%, in reducers vs not, respectively. Mean fat mass change was -2.1±1.9 and -1.1±1.69 in reducers vs not, respectively. A total of 172 (59%) improved lean muscle mass (kg), change was 1.6±1.46kg and -1.6±1.81kg in gainers vs not, respectively. Predictors of fat loss and lean muscle mass improvement were female sex, history of coronary artery disease, pre CR relative VO2, android BF distribution, android/gynoid ratio and interval training during CR (see Table 1). Only Pre-CR lean mass and fat loss after CR predicted muscle gain (see Table 2). While muscle gain (OR 5.79, 95%CI 2.57-13.05, p<0.0001) and pre CR relative VO2, per each mL/kg (OR 0.90, 95%CI 0.84-0.9, p 0.001) were independent predictors after adjusting for age and significant univariate predictors.
Conclusions: Our results highlight the predictors of fat loss and lean muscle gain after CR participation. Muscle gain and exercise capacity in CR were independent predictors of fat loss and lean muscle gain. We here underscore the importance of exercise training and body composition assessment during CR as part of an individualized treatment plan.