Free-living energy expenditure assessed by two different methods in rural Gambian men.
OBJECTIVE
To assess total free-living energy expenditure (EE) in Gambian farmers with two independent methods, and to determine the most realistic free-living EE and physical activity in order to establish energy requirements for rural populations in developing countries.


METHODS
In this cross-sectional study two methods were applied at the same time.


METHODS
Three rural villages and Dunn Nutrition Centre Keneba, MRC, The Gambia.


METHODS
Eight healthy, male subjects were recruited from three rural Gambian villages in the sub-Sahelian area (age: 25 +/- 4y; weight: 61.2 +/- 10.1 kg; height: 169.5 +/- 6.5 cm, body mass index: 21.2 +/- 2.5 kg/m2).


METHODS
We assessed free-living EE with two inconspicuous and independent methods: the first one used doubly labeled water (DLW) (2H2 18O) over a period of 12 days, whereas the second one was based on continuous heart rate (HR) measurements on two to three days using individual regression lines (HR vs EE) established by indirect calorimetry in a respiration chamber. Isotopic dilution of deuterium (2H2O) was also used to assess total body water and hence fat-free mass (FFM).


RESULTS
EE assessed by DLW was found to be 3880 +/- 994 kcal/day (16.2 +/- 4.2 MJ/day). Expressed per unit body weight the EE averaged 64.2 +/- 9.3 kcal/kg/d (269 +/- 38 kJ/kg/d). These results were consistent with the EE results assessed by HR: 3847 +/- 605 kcal/d (16.1 +/- 2.5 MJ/d) or 63.4 +/- 8.2 kcal/kg/d (265 +/- 34kJ/kg/d). Physical activity index, expressed as a multiple of basal metabolic rate (BMR), averaged 2.40 +/- 0.41 (DLW) or 2.40 +/- 0.28 (HR).


CONCLUSIONS
These findings suggest an extremely high level of physical activity in Gambian men during intense agricultural work (wet season). This contrasts with the relative food shortage, previously reported during the harvesting period. We conclude that the assessment of EE during the agricultural season in non-industrialized countries needs further investigations in order to obtain information on the energy requirement of these populations. For this purpose the use of the DLW and HR methods have been shown to be useful and complementary.
Heini
A F
AF
Department of Nutrition Sciences, University of Alabama at Birmingham 35294-3360, USA.
Minghelli
G
G
Diaz
E
E
Prentice
A M
AM
Schutz
Y
Y
D000328:Adult; D001481:Basal Metabolism; D001823:Body Composition; D002153:Calorimetry, Indirect; D003903:Deuterium; D004734:Energy Metabolism; D015444:Exercise; D005714:Gambia; D006339:Heart Rate; D006801:Humans; D008297:Male; D012044:Regression Analysis; D012424:Rural Population
D003903:Deuterium