High level of free-living energy expenditure in rural Gambian men: lack of behavioural adaptation between low and normal BMI groups.
OBJECTIVE
To explore if a behavioural adaptation--such as a reduction in total free-living energy expenditure (EE)--occurs in Gambian individuals with low body mass index (BMI < 18.5 kg/m2).


METHODS
Cross-sectional comparative study of young Gambian men living in rural area.


METHODS
Total daily free-living EE was assessed from the heart rate method (using individual regression line between heart rate and EE determined in a respiration chamber).


METHODS
One group of underweight men (n = 26, BMI = 17.2 +/- 0.2 kg/m2 compared to a control group with normal BMI matched for age and height (n = 28, BMI = 23.3 +/- 0.2 kg/m2).


RESULTS
In absolute value, the free-living EE of the low BMI group was significantly lower than that of the control group (10.3 +/- 0.5 vs 12.7 +/- 0.5 MJ/d, P < 0.001). Expressed per kg body weight or kg fat-free mass, the differences between the two groups disappeared. In both groups, the level of free-living EE averaged approximately two times the basal metabolic rate.


CONCLUSIONS
Rural Gambian men with low BMI and normal BMI have similar levels of free-living EE when normalized for body weight or fat-free mass. Their level of activity can be judged as moderate to heavy. Within the range of BMIs studied there was no evidence of behavioural adaptation to save energy.
Della Bianca
P
P
Institut de physiologie, Lausanne/Switzerland.
Jéquier
E
E
Schultz
Y
Y
D000222:Adaptation, Physiological; D000328:Adult; D000886:Anthropometry; D001823:Body Composition; D015992:Body Mass Index; D002153:Calorimetry, Indirect; D003430:Cross-Sectional Studies; D004734:Energy Metabolism; D005714:Gambia; D006339:Heart Rate; D006801:Humans; D008297:Male; D012424:Rural Population