CHANGES IN BODY COMPOSITION INDUCED BY DIET AND EXERCISE

C. SABOU*, S. CATANĂ*, A. NEAGU*,**, S. ARJOCA***, MONICA NEAGU*#, V. PUPĂZAN*
*Center for Modeling Biological Systems and Data Analysis, ”Victor Babeș” University of Medicine and Pharmacy, Timișoara, Romania
**Department of Physics & Astronomy, University of Missouri, Columbia, U.S.A.
***Department of Physics, West University of Timișoara, Timișoara, Romania

Nutritional status is commonly described in terms of the body mass index (BMI), defined as body mass (kg) divided by height (m) squared. Adults with BMI ≥ 30 kg/m2 are classified as obese by the World Health Organization. BMI, however, is a poor indicator of fatness because it does not contain information on the nature and distribution of body mass. Therefore, a more refined analysis of body composition is needed for assessing the benefits of changes in diet and lifestyle. The simplest, two-compartment model of body composition distinguishes fat and fat-free body. By measuring the mass of these components, one can describe fatness in terms of per cent body fat (%BF), as well as the fat mass index (FMI), defined as fat mass (kg) divided by height (m) squared. These quantities can be measured, for example, by densitometry. In this work, we report changes in body composition as a result of a 4 week program of diet and exercise, specifically designed to gain muscle mass while lowering %BF and FMI. The diet aimed at decreasing specific macronutrients to ensure a slight, steady calorie deficit. It was high in protein, supplying most of the energy expenditure of the body, as well as nutrients needed to stimulate muscle growth. The exercise program, based on resistance training combined with conditioning training, was meant to stimulate muscle growth. The resistance training, involving heavy muscle contractions, was more likely to use up glucose. The conditioning training (done in the morning, on an empty stomach, with a low, but steady blood sugar) increased lipolysis and boosted the metabolic rate, resulting in a higher calorie consumption throughout the day. We performed weekly measurements, after overnight fasting, by air displacement plethysmography using the BOD POD Body Composition Tracking System, ultrasound anthropometry (US), and bioelectrical impedance analysis (BIA). The subject did weekly blood tests (blood cells count, liver enzymes) to ensure that the training and diet programs are safe. Body mass management requires a careful balance between diet and exercise, and body monitoring techniques are essential in assuring this balance.
Key words: air displacement plethysmography, bioelectrical impedance analysis, ultrasound.

Corresponding author’s e-mail: neagu.monica@umft.ro.

Full text: PDF