Lifestyle changes such as following a hypocaloric diet and regular physical exercise are recognized as effective non-pharmacological interventions to reduce body fat mass and prevent cardiovascular disease risk factors.
Purpose: To evaluate the interactions of a higher protein (HP) vs. a lower protein (LP) diet with or without a concomitant progressive resistance training program (RT) on body composition and lipoprotein profile in hypercholesterolemic obese women.
Methods: Retrospective study derived from a 16-week randomized controlled-intervention clinical trial. Twenty five sedentary, obese (BMI: 30-40 kg/m²) women, aged 40-60 with hypercholesterolemia were assigned to a 4-arm trial using a 2 x 2 factorial design (Diet x Exercise). Prescribed diets had the same calorie restriction (-500 kcal/day), and were categorized according to protein content as: lower protein (< 22% daily energy intake, LP) vs. higher protein (> 22% daily energy intake, HP). Exercise comparisons involved habitual activity (control) vs. a 16-week supervised whole-body resistance training program (RT), two sessions/wk.
Results: A significant decrease in weight and waist circumference was observed in all groups. A significant decrease in LDL-C and Total-Cholesterol levels was observed only when a LP diet was combined with a RT program, the RT being the most determining factor. Interestingly, an interaction between diet and exercise was found concerning LDL-C values.
Conclusion: In this study, resistance training plays a key role in improving LDL-C and Total-Cholesterol; however, a lower protein intake (< 22% of daily energy intake as proteins) was found to achieve a significantly greater reduction in LDL-C.