Cardiorespiratory fitness and physical activity in Luo, Kamba, and Maasai of rural Kenya.

BACKGROUND: Although habitual physical activity energy expenditure (PAEE) and cardio-respiratory fitness (CRF) are now well-established determinants of metabolic disease, there is scarcity of such data from Africa. The aim of this study was to describe objectively measured PAEE and CRF in different ethnic populations of rural Kenya. METHODS: A cross-sectional study was done among 1,099 rural Luo, Kamba, and Maasai of Kenya. Participants were 17-68 years old and 60.9% were women. Individual heart rate (HR) response to a submaximal steptest was used to assess CRF (estimated VO(2) max). Habitual PAEE was measured with combined accelerometry and HR monitoring, with individual calibration of HR using information from the step test. RESULTS: Men had higher PAEE than women (∼78 vs. ∼67 kJ day(-1) kg(-1) , respectively). CRF was similar in all three populations (∼38 and ∼43 mlO(2) ·kg(-1) min(-1) in women and men, respectively), while habitual PAEE measures were generally highest in the Maasai and Kamba. About 59% of time was spent sedentary (<1.5 METs), with Maasai women spending significantly less (55%). Both CRF and PAEE were lower in older compared to younger rural Kenyans, a difference which was most pronounced for PAEE in Maasai (-6.0 and -11.9 kJ day(-1) kg(-1) per 10-year age difference in women and men, respectively) and for CRF in Maasai men (-4.4 mlO(2) ·min(-1) kg(-1) per 10 years). Adjustment for hemoglobin did not materially change these associations. CONCLUSION: Physical activity levels among rural Kenyan adults are high, with highest levels observed in the Maasai and Kamba. The Kamba may be most resilient to age-related declines in physical activity.

Post-prandial glucose levels and consumption of omega 3 fatty acids and saturated fats among two rural populations in Kenya.

BACKGROUND: Amount and quality of dietary fat modifies glucose tolerance. Omega 3 Fatty Acids (n-3F A) are polyunsaturated fats, mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found primarily in fish and they have a positive effect on glucose tolerance. OBJECTIVE: To compare risk of type 2 diabetes mellitus (T2DM), as demonstrated thourough impaired glucose tolerance (IGT), and n-3FA intake among two rural populations. DESIGN: A descriptive, cross-sectional comparative study. SETTING: Bondo District (Luo Community) and Kericho District (Kipsigis Community) of the Lake Victoria basin of Kenya. SUBJECTS: Sample of 150 individuals, aged above 18 years was randomly selected from each of the two communities. INTERVENTIONS: Impaired glucose tolerance (IGT) was measured according to World Health Organisation diagnostic criteria. The intake of n-3FA was determined using a 24 hour dietary recall and food frequency schedule. Data was analysed using SPSS and Pearson Correlation Coefficient was used to test correlation between n-3FA consumption and IGT. The inter-group comparisons were done using the t-test and analysis of variance. RESULTS: The prevalence of IGT was 11.8% among the Kipsigis and 4.8% among the Luo (P<0.001). The mean EPA and DHA intake was found to be 0.29 g/day and 0.34 g/day respectively among the Luo and 0.01 g/day and 0.01 g/day among the Kipsigis (P<0.001). The relationship between 2 hour post-prandial glucose level and consumption of DHA was (r=-0.111, p<0.05), EPA (r=-0.123, p<0.05), polyunsaturated fatty acids (r=-0.128, p<0.05) and saturated fats (r=-0.002, p=0.973). CONCLUSION: The levels of IGT were significantly lower (P<0.001) among the Luo, than among the Kipsigis. There was also evidence of significant inverse relationship between IGT and consumption of n-3FA and polyunsaturated fatty acids (PUFA) but no association between saturated fats intake and IGT. The saturated fat ingested did not affect the level of post-prandial glucose. The Luo who consumed higher n-3FA amounts, recorded lower levels of IGT than the Kipsigis who had significantly lower consumption. RECOMMENDATIONS: Effective screening methods should be used at the existing health units to determine risk factors of type 2 diabetes mellitus like IGT among patients. This could help in advising them accordingly on lifestyle changes, especially concerning diet and beneficial fats.

Food and macronutrient intake of elite kenyan distance runners.

The food and macronutrient intake of elite Kenyan runners was compared to recommendations for endurance athletes. Estimated energy intake (EI: 2987 +/- 293 kcal; mean +/- standard deviation) was lower than energy expenditure (EE: 3605 +/- 119 kcal; P < 0.001) and body mass (BM: 58.9 +/- 2.7 kg vs. 58.3 +/- 2.6 kg; P < 0.001) was reduced over the 7-d intense training period. Diet was high in carbohydrate (76.5%, 0.4 g/kg BM per day) and low in fat (13.4 %). Protein intake (10.1 %; 1.3 g/kg BM per day) matched recommendations for protein intake. Fluid intake was modest and mainly in the form of water (1113 +/- 269 mL; 0.34 +/- 0.16 mL/kcal) and tea (1243 +/- 348 mL). Although the diet met most recommendations for endurance athletes for macronutrient intake, it remains to be determined if modifying energy balance and fluid intake will enhance the performance of elite Kenyan runners.