Ellisras Longitudinal Study 2017: The relationship between waist circumference, waist-to-hip ratio, skinfolds and blood pressure among young adults in Ellisras, South Africa (ELS 14).

BACKGROUND: Obesity and hypertension are major risk factors for non-communicable diseases in the world today. The relationship between indicators of obesity and blood pressure needs attention in the rural South African population. AIM: This study examined the relationship between anthropometric parameters and blood pressure (BP) among young adults in the Ellisras rural area of South Africa. METHODS: A total of 742 (365 females and 377 males) young adults aged 22 to 30 years, who were part of the Ellisras Longitudinal Study (ELS), participated in the research. Anthropometric and BP measurements were taken using the protocol of the International Society for the Advancement of Kinanthropometry (ISAK). Linear regression was used to determine the relationship between anthropometric parameters and BP. The risk of developing hypertension among young Elisras adults was evaluated using logistic regression. RESULTS: The results indicted a higher but on-significant prevalence of hypertension in men (2.7%) than women (2.4%). Linear regression showed a significant positive (p < 0.05) association between waist circumference and systolic BP (ß = 0.273, 95% CI: 0.160-0.386), even after being adjusted for age and gender (ß = 253, 95% CI: 0.127-0.343). The risk for developing hypertension was significant ( p < 0.05) for waist circumference (OR = 2.091, 95% CI: 1.129-3.871) after adjustment for age and gender. CONCLUSIONS: Of all anthropometric parameters, waist circumference was most significantly associated with BP ( p < 0.05). Anthropometric indicators of obesity were strong predictors of hypertension among young adults in the Ellisras rural area.

Profile of the female athlete triad among elite Kenyan endurance athletes and non-athletes

Women participating in endurance sports are at risk of presenting with low energy availability (EA), menstrual dysfunction (MD), and low bone mineral density (BMD), collectively termed the female athlete triad (FAT or TRIAD). Therefore, the purpose of the study was to determine the profile of the TRIAD among elite Kenyan female athletes and among non-athletes. There were 39 participants (athletes: 25, non-athletes:14) who provided the data for this study. Exercise energy expenditure (EEE) was deducted from energy intake (EI), and the remnant energy normalized to fat free mass (FFM) to determine energy availability (EA). Weight of all food and liquid consumed during three consecutive days determined EI. EEE was determined after isolating and deducting energy expended in exercise or physical activity above lifestyle from the total energy expenditure output as measured by Actigraph GT3X+. Dual energy x-ray absorptiometry (DXA) determined both FFM and BMD. Menstrual function was determined from a daily temperature-menstrual log kept by each participant for nine continuous months. Low EA (<45 kcal/kgFFM.d-1) was evident in 61.53% of the participants (athletes: 28.07 ±11.45 kcal/kgFFM.d-1, non-athletes: 56.97 ±21.38 kcal/kgFFM.d-1). The overall 36% MD seen among all participants was distributed as 40% among the athletes, and 29% among non-athletes. None of the athletes was amenorrheic. Low BMD was seen in 79% of the participants (athletes: 76%, non-athletes:86%). Overall, 10% of the participants (athletes: 4, non-athletes: 0) showed simultaneous presence of all three components of the TRIAD. The Independent sample t-test showed significant difference (t=5.860; p< 0.001) in prevalence of the TRIAD between athletes and non-athletes. The hypothesized higher prevalence of the TRIAD among athletes compared to non-athletes was partially accepted. To alleviate conditions arising from low EA, both athletes and their coaches need regular education on how to ensure they adequately meet specific dietary and nutritional requirements for their competition events

Association between energy availability and menstrual function in elite Kenyan runners

Low energy availability (EA) has been recognized as an instigator of menstrual dysfunction and subsequent hypoestrogenism that leads to deterioration in bone health. Elite Kenyan male athletes have been reported to often function under low energy balance. Therefore, the purpose of this study was to determine EA and menstrual function (MF) among elite Kenyan female athletes; and to explore the association between EA and MF in the athletes. The data were collected from 25 elite Kenyan runners and 14 non-athletes. Energy intake (EI) minus exercise energy expenditure (EEE) normalized to fat free mass (FFM) determined EA. EI was determined through weight of all food and liquid consumed over three consecutive days. EEE was determined after isolating and deducting energy expended in exercise or physical activity above lifestyle level from the total energy expenditure output as measured by Actigraph GT3X+. FFM was assessed using DXA. A daily temperature-menstrual log kept for nine continuous months was used to establish menstrual function. Overall, EA below 45 kcal/kgFFM.d-1 was seen in 61.53% of the participants (athletes: 28.07 ±11.45 kcal/kgFFM.d-1, non-athletes:56.97 ±21.38 kcal/kgFFM.d-1). Results on menstrual dysfunction were as follows: oligomenorrhea (athletes: 40%; non-athletes: 14.3%) and amenorrhea (non-athletes: 14.3%). None of the athletes were amenorrheic. Results did not show any significant association between EA and MF, but the low to sub-optimal EA among elite Kenyan female athletes raises concern for their future menstrual and bone health. . Educating the athletes and coaches will enhance achievement of the specific dietary and nutritional needs appropriate to their competition events

Body fat percentage of urban South African children: implications for health and fitness.

OBJECTIVE: To explore gender and racial profiling of percentage body fat of 1136 urban South African children attending public schools in Pretoria Central. METHODS: This is a cross-sectional survey of 1136 randomly selected children (548 boys and 588 girls) aged 9-13 years in urban (Pretoria Central) South Africa. Body mass, stature, skinfolds (subscapular and triceps) were measured. Data were analysed using descriptive statistics (means and standard deviations). Differences in the mean body fat percentage were examined for boys and girls according to their age group/race, using independent t-test samples. RESULTS: Girls had a significantly (p = 0.001) higher percentage body fat (22.7 ± 5.7%, 95% CI = 22.3, 23.2) compared to boys (16.1 ± 7.7%, 95% CI = 15.5, 16.8). Percentage body fat fluctuated with age in both boys and girls. Additionally, girls had significantly (p = 0.001) higher percentage body fat measurements at all ages compared to boys. Viewed racially, black children (20.1 ± 7.5) were significantly (p = 0.010) fatter than white children (19.0 ± 7.4) with a mean difference of 4.0. Black children were fatter than white children at ages 9, 10, 12 and 13 years, with a significant difference (p = 0.009) observed at age 12 years. CONCLUSION: There was a considerably higher level of excessive percentage body fat among school children in Central Pretoria, South Africa, with girls having significantly higher percentage body fat compared to boys. Racially, black children were fatter than white children. The excessive percentage body fat observed among the children in this study has implications for their health and fitness. Therefore, an intervention programme must be instituted in schools to prevent and control possible excessive percentage body fat in this age group.

Effects of a mat Pilates programme on body composition in elderly women.

BACKGROUND: With ageing, the ability to mobilize fat is reduced and this, coupled with gradual decrease in lean body mass (LBM) from lessened exercise, allows for an increased body fat percentage (%BF). Exercising is considered a key to maintaining an appropriate body mass (BM), as it improves fat oxidation, while maintaining LBM. Although the effects of endurance and/or resistance training on fat mass (FM) and LBM in the elderly have well been established, limited data are forthcoming regarding the effects of Pilates as a training modality on these variables in the elderly. OBJECTIVE: The present study was therefore conducted to determine the effects of a mat Pilates programme on body fat in elderly women. METHODS: Fifty sedentary, apparently healthy females aged 60 years and older were randomly assigned a control (CG, n = 25) or an intervention (IG, n = 25) group. The IG took part in an eight-week progressive mat Pilates exercise programme, three times weekly while the CG were instructed to maintain their normal daily activities throughout the eight-week experimental period. All subjects underwent pre- and post-test in which FM and LBM were assessed. RESULTS: Eight weeks of mat Pilates demonstrated a significant (p ≤ 0.05) decrease in % BF (p = 0.016) and FM (p = 0.038), with a significant increase in LBM (p = 0.006), while not showing any significant changes (p ≥ 0.05) in BM (p = 0.979) and BMI (p = 0.992). The CG, however, did not produce any significant (p ≥ 0.05) changes in any of the tested anthropometric variables (BM: p = 0.266; BMI: p = 0.123; % BF: p = 0.516; FM: p = 0.937 and LBM: p = 0.522) after completion of the eight-week Pilates programme. CONCLUSION: An eight-week mat Pilates exercise programme may contradict or even reverse some of the most serious consequences of ageing associated with an increased fat mass and reduced lean body mass in elderly females.

Stature and body mass of Nigerian children aged 9-12 years.

AIM: Mean stature and body mass at selected ages are useful indices of the health and well-being of children in a community. However, such data is not available in school children in Makurdi, Nigeria. The aim of this paper was to present the stature and body mass of children aged 9-12 years in Makurdi, Nigeria, with a view to providing baseline data for these physical characteristics. METHODS: Anthropometric measurements of stature and body mass were taken in cross-sectional study of 2015 children (979 boys and 1036 girls) randomly selected from 19 public primary schools in Makurdi, Nigeria. RESULTS: The girls (Mean stature=138.9; SD=8.1 cm and body mass: 31.5; SD=6.1 kg) were significantly taller and heavier (P≤0.05) than the boys (Mean stature=137.2; SD=7.7 cm and body mass: 29.8; SD=4.4 kg). At all age categories the girls were taller than the boys. Except at age nine, the girls were significantly heavier than the boys at ages 10 to 12 years (p≤ 0.001). Stature and body mass increased with age in both boys and girls. In comparison with the NCHS growth reference, the Nigerian children were significantly shorter and lighter at all the ages than their American peers. CONCLUSION: Lower values of stature and body mass recorded in this sample in comparison with the NCHS standard are probably due to poor living conditions. Periodic monitoring of these anthropometric indicators in the children could provide reliable data for screening those with growth abnormalities so that appropriate health intervention strategies can be instituted.

Using receiver operating characteristic curve analysis in detecting excess adiposity in 9-13-year old South African children.

OBJECTIVE: Little is known concerning the applicability of receiver operating characteristic (ROC) curve analysis in detecting excess adiposity in preadolescent South African children. Therefore, the purpose of this study was to evaluate the sensitivity and specificity of body mass index (BMI) and skinfold thickness: BMI (subcutaneous to overall fat) in detecting excess adiposity in preadolescent urban South African school children. METHODS: This was a cross-sectional survey of 1136 randomly selected children (548 boys and 588 girls) aged 9-13 years old in urban (Pretoria Central) South Africa. Body mass, stature, skinfolds (subscapular, triceps, supraspinale and biceps) and waist circumference were measured. Receiver operating characteristic curve analysis was used to assess the sensitivity and specificity of BMI, and log10 SF4:BMI to detect excess adiposity. Excess adiposity was defined as levels of log10 SF4 greater than the internally derived 85th percentile (log10 SF4 > 85th percentile). RESULTS: Compared to log10 SF4:BMI, BMI had a high specificity (0.88; 95% CI 0.84, 0.90). The log10 SF4:BMI identified excess adiposity with a sensitivity and specificity of 0.62 (95% CI 0.60, 0.67) and 0.68 (95% CI 0.64, 0.70), respectively. Besides, a decrease in overall misclassification with the use of log10 SF4:BMI instead of BMI at the 95th percentile (9.7% versus 27.1%) was observed. CONCLUSION: Similar to other studies, although with varying degrees, the present study confirms that log10 SF4:BMI at conventional cut-off points has a relatively high sensitivity and specificity in detecting excess adiposity, and therefore could be used to identify the excess adiposity in South African children. As such, defining obesity based on population-specific percentiles rather than using cut-off points derived from other geographical settings with contrasting levels of socio-economic development becomes imperative.

Prevalence of body weight disorders among adolescent school girls in Tarka, Nigeria.

AIM: The prevalence of overweight and obesity is increasing worldwide, both in developing and developed countries, and childhood obesity is a serious public health problem. However, there are few studies on prevalence of obesity on Nigerian adolescents in a rural community. Therefore, the aim of this cross-sectional study was to determine the prevalence of overweight and obesity among 722 secondary school female students aged 12-18 years living in Wannune, Tarka, Nigeria. METHODS: Participants were selected by purposive sampling from five schools. Anthropometric measurements of height and weight were measured and body mass index (BMI) calculated. The centres for disease control and prevention (CDC) BMI cut-off points were used to generate four BMI categories as follows: BMI <5th percentile, "underweight'; BMI ≥ 5th to <85th percentile, "normal weight"; BMI ≥ 85th to <95th percentile, "at-risk-of-overweight"; and BMI ≥ 95th percentile, "overweight and obese". RESULTS: Findings indicated that 70.1% of the participants had a normal BMI, 7.5% were overweight/obese while 12.5% at risk of overweight and 9.9% were underweight. The levels of obesity, overweight and underweight observed in our sample is quite higher, and indicates overweight and obesity is even occurring in Nigerian adolescents in a rural settings. CONCLUSION: Given that over-nutrition and under-nutrition are noticeable among adolescents' school girls in Tarka, suggests that policy makers and health professionals should design and implement strategies to prevent body weight disorders in children.

Screening for body-weight disorders in Nigerian children using contrasting definitions.

Several indices for body-weight disorders exist in scientific literature, but it is inconclusive whether or not they can yield comparable results when applied to Nigerian children. The prevalence of weight disorders in Nigerian children was examined using the Centre for Disease Control and Prevention (CDC) body mass index (BMI) for age charts and the International Obesity Task Force's (IOTF) age- and sex-specific BMI cut-off points. Participants were 2015 pupils (979 boys and 1036 girls) aged 9-12 years, attending 19 public primary schools in Makurdi, Nigeria. Stature and body mass were measured using standard techniques. Results were analysed using student t-test and Chi-squared statistics, with the probability level set at

Body composition and physical fitness of undernourished South African rural primary school children.

OBJECTIVE: The purpose of this study was to determine the relationships between the body composition characteristics, body mass index (BMI), sum of skinfolds (SSF), % body fat (%BF), fat-free mass (FFM) and waist-to-hip ratio (WHR), and nine physical fitness items in undernourished rural primary school children in Ellisras, South Africa. DESIGN: A cross-sectional study. SETTING: The study consisted of 462 boys and 393 girls who were aged 7-14 y. MEASUREMENTS: Five body composition measures were assessed: BMI, SSF, %BF, FFM and WHR. Nine physical fitness test items were assessed: standing long jump, bent arm hang, sit-ups, 10 x 5 m shuttle run, 50 m sprint, 1600 m run, flamingo balance, sit and reach, plate tapping. RESULTS: BMI was highly correlated with FFM (r = 0.7, P < 0.001). In line with findings from Western countries, regression coefficients (B) showed that children with higher BMI or SSF performed worse in bent arm hang (girls, B = -0.84, P < 0.001, and B = -0.06, P = 0.02, respectively) and in 1600m run (B = 6.68, P < 0.001). BMI was significantly associated with flamingo balance (B = 0.26, P = 0.04). WHR was positively associated with bent arm hang (B = 9.37, P = 0.03), and inversely with sit and reach (B = -7.48, P = 0.01). In contrast, significant relationships were found between BMI and standing long jump (B = 0.74, P = 0.04), sit and reach (B = 0.51, P < 0.001), flamingo balance (B = 0.26, P = 0.04) and plate tapping (B = -19, P = 0.01). SSF was significantly associated with sit and reach (B = 0.04, P = 0.03). Significant inverse associations were found between FFM and bent arm hang (girls, B = -0.06, P = 0.05), 1600 m run (girls, B = -2.33, P = 0.003) and 50 m run (boys, B = -0.11, P = 0.006). FFM was significantly associated with standing long jump (boys, B = 0.99, P < 0.001; girls, B = 0.73, P < 0.001), flamingo balance (B = 0.17, P < 0.001), and with sit and reach (boys, B = 0.59, P = 0.03). CONCLUSION: In the present study in undernourished children, body composition was significantly related to physical fitness, but not always in the expected direction. It is therefore important to note that in this population, BMI should not be interpreted as a measure of fatness/overweight, but rather as an indicator of muscle mass.

Stability of somatotypes in 4 to 10 year-old rural South African girls.

In 1996, a mixed Ellisras longitudinal study (ELS) was initiated to assess the stability of somatotypes in 408 girls who comprised 99 pre-school and 309 primary school children in Ellisras rural area in the Northern Province of South Africa. The children's somatotype was assessed using the Heath-Carter anthropometric method. Anthropometric dimensions were taken according to the protocol of the International Society for the Advancement of Kinanthropometry (ISAK). The most stable pre-school and primary school girl had migratory distances (MDs) of 2.6 and 3.4, respectively, while the least stable pre-school and primary school girl had MDs of 17.9 and 24.4, respectively. The mean somatotype of the pre-school children was mesomorph-ectomorph throughout the complete age range, while the mean somatotype of primary school girls was mesomorph-ectomorph for all the age groups except for the 9.5 years group at which it was in the balanced ectomorph. The inter-age partial correlations for endomorphy and ectomorphy were high and significant, but insignificant with regard to mesomorphy.

Anthropometric assessment of nutritional status of Nigerian children.

Anthropometric evaluations of mid-arm circumference, mid-arm muscle circumference, triceps skinfold, upper arm muscle and fat areas were carried out in 348 healthy Nigerian primary school boys and girls aged 7 to 13 years. Measurements were related to centiles derived from the United States Health and Nutrition examination survey of 1971 to 1974. For all measurements, a large proportion of the subjects fell below the 5th centile. Anthropometric reference standards used to indicate nutritional depletion in developed countries may not be appropriate to assess nutritional status of Nigerian children.

Survey of menstrual function in young Nigerian athletes.

Menstrual function was assessed comparatively in different categories of 155 Nigerian athletes, aged 13-19 years, and 135 nonathletes, aged 12-18 years, who answered questionnaires and were interviewed. Menstruation was more regular and normal in the nonathletes (44%) than the athletes (21%). Although both groups generally had similar patterns of menstrual dysfunction, secondary amenorrhea or oligomenorrhea (O/A) was more prevalent in the athletes (25%) than the nonathletes (10%). Among the athletes, only the distance runners were significantly lighter and leaner than nonathletes and athletes of other sports (P less than 0.05). Regardless of sports activity, oligomenorrheic subjects had substantially lower body weight relative to stature and were leaner than subjects of the other menstrual categories. In the oligomenorrheic group, a greater proportion of the athletes (59%) and nonathletes (57%) had lean body mass values below the 41st percentile. The premenarche-trained athletes (48%) reported a higher incidence of menstrual cycle irregularities than the athletes who began training after the menarche. Results support the role of body composition-related factors in the etiology of exercise-associated O/A.