Influence of exercise training on physiological and performance changes with weight loss in men

Area of Science:

• Exercise physiology
• Nutritional science
• Human metabolism

Background:

• Weight management is crucial for health.
• Dietary interventions are common for weight loss.
• The role of exercise in conjunction with diet requires further elucidation.

Purpose of the Study:

• To investigate the physiological impacts of a weight-loss diet.
• To compare a diet-only approach with combined diet and exercise regimens.
• To assess the effects on body composition, strength, and cardiorespiratory fitness.

Main Methods:

• Thirty-five overweight men were randomized into four groups: control, diet-only, diet with aerobic exercise, and diet with aerobic and strength training.
• Interventions lasted 12 weeks.
• Measurements included body mass, fat mass, fat-free mass, maximal strength (1-RM), peak oxygen consumption, anaerobic power (Wingate test), resting metabolic rate, and serum lipid profiles.

Main Results:

• All dietary groups achieved significant body mass reduction.
• Diet plus exercise groups (DE and DES) showed greater preservation of fat-free mass compared to diet-only (D).
• The diet with aerobic and strength training (DES) group demonstrated significant increases in muscular strength and peak oxygen consumption, while the diet with aerobic exercise (DE) group showed elevated peak oxygen consumption. The diet-only group experienced a decline in power output.

Conclusions:

• A weight-loss diet combined with aerobic and resistance exercise is superior to diet alone.
• This combined approach prevents the loss of fat-free mass and muscular power.
• It also improves body composition, maximal strength, and maximal oxygen consumption.