TITLE:
Bright light enhances the efficiency of physical activity in combination with a restrictive diet
AUTHORS:
Boris B. Pinkhasov, Vera G. Selyatitskaya, Ani R. Karapetyan
KEYWORDS:
Obesity; Bright Light; Physical Activity; Restrictive Diet
JOURNAL NAME:
Health,
Vol.6 No.3,
February
8,
2014
ABSTRACT: The purpose of this study was to analyze the
effectiveness of measures aimed at correcting obesity in women and including
bright light exposure during aerobic exercise combined with a restrictive
diet. A one-stage, randomized study involved 80 obese women aged 20 to 58
years. The inclusion criterion for selecting participants for this research was the presence of primary alimentary-constitutional obesity with body mass index
equal to or higher than 30 kg/m2. All the women were
distributed into three groups according to the set of applied treatments. In
Group 1, the women were on a restrictive diet; in Group 2, the restrictive diet
was accompanied with daily aerobic exercise;
in Group 3, women were exposed to
bright light during exercise. Before and after the treatment course (3
weeks), body weight, waist and hip circumferences were measured; fat amount was
determined by the impedancemetry method; and oxygen consumption was
determined by indirect calorimetry. Women in Group 1 had reduced body weight,
waist and hip circumferences, fat mass and oxygen consumption. Similar
changes were identified in women of Group 2, but weight loss was greater, and
the level of oxygen consumption increased as compared to the baseline. In
women of Group 3, weight loss and increased oxygen consumption were more
pronounced than in those of Group 2. The number of metabolic equivalents (MET)
in women of Group 3 increased to nearly 1, which corresponded to the value of
this index that reflected the resting metabolic rate in patients with normal
body weight. Thus, exposure to bright full-spectrum light increases energy
metabolism and enhances the effectiveness of exercises, despite prolonged
food restriction, which is one of the mechanisms to improve the efficiency of
obesity correction.