Ageing, exercise and food restriction: effects on body composition.

Area of Science:

• Gerontology
• Physiology
• Body Composition

Background:

• Aging is associated with significant changes in body composition.
• Understanding the impact of lifestyle interventions on age-related body composition shifts is crucial.

Purpose of the Study:

• To reevaluate the effects of aging on body composition in rats.
• To compare the impact of exercise versus food restriction on body fat content during aging.

Main Methods:

• Long-term study involving sedentary, freely eating, and exercising (swimming) male Long-Evans rats.
• Inclusion of a food-restricted group to match the body weight of exercising rats.
• Regular assessment of body weight, body fat content, lean body mass, and protein content.

Main Results:

• Body fat content increased progressively with age in sedentary rats.
• Daily swimming significantly reduced body fat and body weight.
• Food restriction substantially lowered body fat content compared to sedentary controls.
• Exercise offered protection against lean body mass decline up to 18 months of age.

Conclusions:

• Lean body mass declines with age in rats, with fat mass increasing to compensate.
• Exercise is highly effective in mitigating age-related increases in body fat.
• Exercise may delay the age-related decline in lean body mass, while food restriction primarily impacts fat mass.