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00005768-201210000-0001900005768_2012_44_1978_musa_cardiorespiratory_10miscellaneous< 113_0_14_6 >Medicine & Science in Sports & Exercise©2012The American College of Sports MedicineVolume 44(10)October 2012p 1978–1985Cardiorespiratory Fitness, Fatness, and Blood Pressure Associations in Nigerian Youth[APPLIED SCIENCES]MUSA, DANLADI I.1,2; WILLIAMS, CRAIG A.21Human Performance Laboratory, Department of Human Kinetics and Health Education, Benue State University, Makurdi, NIGERIA; and 2Children’s Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, Devon, UNITED KINGDOMAddress for correspondence: Craig A. Williams, Ph.D., Children’s Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St. Luke’s Campus, Heavitree Road, Exeter, EX1 2LU, United Kingdom; E-mail: for publication November 2011.Accepted for publication April 2012.ABSTRACTPurpose: This study aimed to examine the independent associations of cardiorespiratory fitness (CRF) and body fatness with resting blood pressure (BP) in children (9–11 yr) and adolescents (12–15 yr) in Benue State of Nigeria.Methods: A total of 3243 children (n = 1017) and adolescents (n = 2226) were evaluated for aerobic fitness, body fatness, resting preexercise BP and recovery BP at minutes 1, 5, and 10 after a progressive aerobic cardiovascular endurance run test. Regression models, controlling for age and recovery BP at 1, 5, and 10 min after the progressive aerobic cardiovascular endurance run, determined the associations of independent variables with the dependent variables.Results: Fatness and fitness were independent predictors of resting BP among participants, and the relationship of fatness with BP was more robust in adolescents than in children. In all cases, the relationships were stronger in boys than in girls. Combined fitness and fatness in predicting BP was modest (R2 = 1%–3%) after controlling for age and postexercise BP. Postexercise BP was a major determinant of resting BP in both groups (R2 = 23%–93%). In adolescents, fatter boys had 1.9 times likelihood of systolic HTN compared with leaner peers. Systolic and diastolic BP scores varied by fit–fat groups, the fit–low-fat group demonstrated the most favorable BP profiles, whereas the unfit–high-fat group showed the most adverse profiles.Conclusions: Irrespective of fatness, participants with higher CRF had more favorable BP profiles compared with their fat–unfit peers.Hypertension (HTN) has been identified as one of the major risk factors involved in the pathogenesis of CHD, a major cause of mortality and morbidity worldwide (6). It has been observed that HTN is the cause of one in eight deaths, making it the third leading killer worldwide (38). Although HTN, like many other CVD risk factors, is an adult health problem, previous studies have documented that it may begin in adolescence or even earlier in childhood (6,18). In the past, extensive studies on CVD risk factors have been conducted in different child and adolescent populations (6,39), identifying HTN as a potent antecedent of CHD. So far, no similar studies have been conducted with African school children. High blood pressure (BP) tracks from childhood to adulthood (37), implying that children and adolescents with BP ranking high or low tend to retain the ranking later in life. Therefore, if individuals who are at risk of this disorder are identified early, suitable intervention (lifestyle) strategies can be initiated, which could enhance better health prospects later in life.HTN is becoming a major pediatric health problem globally because the increasing prevalence of the disorder has been recently reported in many countries, including those from Africa, for instance Nigeria (11) and South Africa (25). Although the specific etiology of HTN is unknown, elevated body fat levels and low physical fitness have been found to be major predisposing factors (10,23). For example, Londe et al. (20) reported that 53% of children age 4–15 yr with HTN were obese. Furthermore, both cross-sectional and longitudinal studies in children and adolescents have demonstrated that overweight and obese participants exhibit higher resting BP than their lean counterparts in a dose–response manner (23,36). The relationship between cardiorespiratory fitness (CRF) or physical activity and HTN is well documented in the adult population, indicating that people with low fitness are at increased risk of HTN (2,32). Although far from conclusive, there is emerging evidence toward a similar trend in the pediatric population (5,10).The effect of aerobic fitness and body fatness on CHD risk has been widely explored in adults, but studies in children are fewer with conflicting results (14,17,35). In one study investigating the relationship among aerobic fitness, fatness, and CHD among 12- to 13-yr-old Welsh children, Thomas et al. (35) found fatness rather than fitness was independently related to CHD risk factors, including BP. In this study, fatness was the only independent predictor of systolic BP (SBP) and diastolic BP (DBP). In contrast, Koley (17) involving 180 college students age 19–26 yr found fitness to be related to both SBP and DBP in both boys and girls, whereas fatness was not significantly correlated with both variables. In other studies involving 7- to 12-yr-olds (5,14), neither fatness nor fitness was significantly correlated with BP. These equivocal findings call for further research to clarify the relationship of fitness and fatness with BP in the pediatric population.Nigeria, like many countries, has witnessed a remarkable change in lifestyle, which has resulted in many chronic health problems, even among young people (3). Although the importance of maintaining optimal fitness and healthy weight has been examined among children in developed countries, no such studies in African children have been conducted. As Nigeria is a developing country, the consequences of HTN will be more severe as the health facilities to manage the disorder are scarce. Therefore, there is a need to examine the relationship of fitness and fatness with resting BP in this population. A better understanding of this association will provide support for the long-term promotion of physically active lifestyles that could lead to improved CRF and reduce the risk of subsequent disease among youth including overweight children.The purpose of this study was to examine the independent and combined associations of CRF and body fatness on resting BP in school-age boys and girls in the Benue State of Nigeria. Specifically, this study examined the relationship among CRF, body mass index (BMI), and resting BP in children and adolescents. The study also determined whether BP values varied among fatness categories by fitness levels. Thus, we hypothesized that CRF would attenuate BP values regardless of fatness status. A secondary purpose was to determine the contribution of postexercise BP in explaining variations in resting BP. To our knowledge, no previous study on the relationship of fitness or fatness with BP has included recovery BP among the determinants of resting BP.METHODSParticipantsFemale and male child and adolescent participants age 9–15 yr were recruited from the Benue State of Nigeria. The volunteer participants were selected from each of the three senatorial districts (Benue North, Benue Central, and Benue South). Benue State is an agrarian state located within the North Central geopolitical zone of Nigeria. The study covered 21 schools (10 primary and 11 secondary schools). Multistage and systematic sampling techniques were used to select 3243 black African youths. In the first stage, 21 schools (7 from each senatorial district) were randomly selected from 1271 schools within the study area. In the second stage, children and adolescents were selected in a systematic manner from the school registers and were asked to participate in the study. In each selected class, every fifth child starting from the first or second on the class list was selected to participate in the study. At the time of data collection, all children and adolescents were apparently healthy and had not participated in any organized exercise program for at least 6 months before the study. Participants who were sick as indicated by their medical records were excluded from the study. The purpose and procedure of the tests were fully explained to participants after obtaining permission from the heads of school. The research protocol was approved by the ethics review board of the institution, and written consents of parents and assent of children were obtained before participation. All procedures were in accordance with those outlined in the Helsinki Declaration.Anthropometric characteristicsParticipants’ physical characteristics were measured according to standard procedures (22). Body mass and stature were measured indoors in each school with the aid of an electronic weighing scale (Seca digital floor scale, Sec-880; Seca, Birmingham, United Kingdom) and a wall-mounted stadiometer (model Sec-206; Seca). Stature was measured to the nearest 0.1 cm. Body mass was measured with participants in minimal clothing to the nearest 0.1 kg. Participant’s BMI (kg·m−2) were determined. BMI was used to estimate body fatness. Both the triceps and medial calf skinfold thicknesses were measured on the right side of participants’ body with the aid of Harpenden skinfold calipers (Creative Health Products, Ann Arbor, MI). All measurements were taken twice, and the average of the two was recorded. The revised regression equations of Slaughter, Lohman, and Boileau for black children (15) were used to estimate percentage fat from the sums of triceps and medial calf skinfolds:Black boys (8–17 yr): % fat = 0.735 (∑2 SKF) + 1.0Black girls (8–17 yr): % fat = 0.610 (∑2 SKF) + 5.1where ∑SKF = sum of skinfolds. Fat-free mass was computed by subtracting participants’ fat mass from their total body mass.Participants were categorized into two groups based on their BMI values according to the FITNESSGRAM revised data (34). On the basis of age, boys who had BMI values from 13.7 to 26.6 kg·m−2 or below were categorized as healthy fitness levels (healthy fitness zone [HFZ]) or low fat. The corresponding BMI for girls was 13.5–25.0 kg·m−2. Boys and girls who had values above the upper levels were categorized as overweight or high fat.The waist circumference was measured with a retractable metal tape at the level of umbilicus midway between the lower rib margin and the iliac crest at the end of a quiet expiration to the nearest 0.1 cm. Two measurements were made, and the average was recorded. The waist circumference served as an estimator of abdominal fat (21). For consistency in all the anthropometric measurements, research assistants measured the same variable throughout the data collection period.CRFThis was assessed using the progressive aerobic cardiovascular endurance run (PACER) protocol. The PACER is a multistage aerobic capacity test adapted from the 20-m shuttle run test that progresses in intensity. The PACER is a widely used, valid, and reliable test of aerobic fitness in children and adolescents (7). This test was selected over other measures of aerobic fitness because it has been shown to enhance motivation especially among children and youth (7). Participants ran back and forth between two lines 20 m apart. The running speed starts at 8.5 km·h−1 and increases by 0.5 km·h−1 each minute. Participants ran in accordance with the audio signals emitted from the PACER CD (34). The reliability of this test has been reported to be 0.89–0.93 (19). All ran in groups of 10, with research assistants counting the number of laps covered during the test. A 20-m distance constituted a lap. The test was terminated when a participant could no longer follow the set pace on two successful shuttles or withdrew voluntarily. The number of laps completed by each participant was used to estimate their CRF (19). To assess the relationship between CRF and BP, the total sample was divided into two groups on the basis of each participant’s completed number of laps according to the FITNESSGRAM sex and age revised health-related cut points (34). For boys and girls, the cut points of 23–94 and 7–61 laps were used as HFZ, respectively. Children who achieved HFZ were categorized as “fit,” and those who achieved below the HFZ were categorized as “unfit.”Blood pressureBlood pressure measurements were taken in the morning while participants occupied a sitting position after 10 min of rest according to the protocol of Resaland et al. (29). The resting SBP, DBP, and pulse rate were monitored on each participants’ right arm using appropriate cuff sizes with an automated digital BP monitor (HEM-705 CP; Omron, Tokyo, Japan). This instrument operates on an oscillometric principle and has been shown to be accurate (27). Measurements were taken twice at 2-min intervals, and the average of the two readings was recorded. If the two measurements differed by ≥2 mm Hg, the protocol was repeated to ensure that the difference did not exceed this value. The mean arterial pressure (MAP) was computed using the formula: DBP + 0.33 × pulse pressure. The standards used for those who were above the level of risk of systolic (≥130 mm Hg) and diastolic (≥85 mm Hg) HTN were those defined by the International Diabetic Federation for 10- to 16-yr-olds (40). SBP and DBP were obtained from a subsample of 660 (children = 206, adolescents = 454) participants during recovery after PACER test at 1, 5, and 10 min while seated. This is because it has been reported that delayed recovery of BP especially SBP after exercise is associated with an increased risk of HTN (31). Throughout the duration of the project, all tests were performed in the same order by the same members of the testing team.Data analysisDescriptive statistics (mean ± SD) of measured and derived variables were used to characterize the sample. The independent-samples t-test was used to test for differences in physical characteristics, performance, and hemodynamic measures between boys and girls. Using the categorical variables for both fitness and fatness, participants were categorized into four groups: 1) “fit and low fat,” 2) “fit and high fat,” 3) “unfit and low fat,” and 4) “unfit and high fat.” Differences across fitness/fatness groups were assessed by one-way ANOVA and Bonferroni comparison method. Analyses were performed separately for each age group and gender. Pearson product–moment coefficients were used to assess the relationship among CRF, fatness, and BP. Hierarchical multiple regression analyses were conducted to determine the independent and combined associations between the independent variables (CRF and BMI) and the dependent variables (SBP and DBP) in the subsample. All analyses were adjusted for age and postexercise SBP (SBP1, SBP5, and SBP10) and DBP (DBP1, DBP5, and DBP10) levels at 1, 5, and 10 min. The independent association of CRF and fatness with BP was further examined using binary logistic regression analysis. Separate analyses were performed for boys and girls in both the children and adolescent groups. Odd ratios (OR) of being at risk of HTN were calculated between fitness and fatness categories. The amount of variation in the dependent variable explained by the model was determined using the Cox and Snell R square and the Negelkerke R square (28). Models were adjusted for one potential confounding variable (age). Because of absenteeism and incomplete data, of the 3400 participants, 3243 (1017 children and 2226 adolescents) completed the measurements and their data included in statistical analysis. This amounted to a participation rate of 95.4%. All statistical analyses were performed using SPSS (Windows version 18; SPSS, Inc., Chicago, IL) at a probability level of ≤0.05.RESULTSParticipants’ anthropometric, hemodynamic, demographic characteristics, and the zero-order correlation coefficients between CRF and fatness for all gender and age groups are presented in Table 1. Prevalence of HTN among participants is presented in Table 2. The average prevalence of risk of systolic HTN combined among children was 8.7% (5.6% in boys, 11.5% in girls). That for the adolescents was 16.7% (12.5% in boys, 20.4% in girls). The proportion of children at risk of diastolic HTN in total was 16.1% (16.3% in boys, 16.0% in girls). That in the adolescents was 14% (13.4% in boys, 14.5% in girls). In all cases, the prevalence of diastolic HTN was higher than that of systolic HTN, and systolic HTN was higher in girls than in boys in both age groups. Among the younger age group, the prevalence of overweight was 2.6% (2.7% in boys, 2.4% in girls). Among the adolescents, it was 4.6% (4.4% in boys, 4.7% in girls). The prevalence of low fitness among children was 12.1% (20.4% in boys, 4.5% in girls). That among adolescents was 42.8% (42.8% in boys, 33.4% in girls). The correlation coefficients indicate generally weak relationships for all groups.TABLE 1 Physical and hemodynamic characteristics of participants (n = 3243).TABLE 2 Prevalence of HTN among study participants (n = 3243).Among the children (Table 1), girls generally displayed significantly (P < 0.05) higher values than boys did in all measures except for lean body mass and the PACER in which boys had higher values. However, age, BMI, and DBP were similar across gender (P > 0.05). Similar results were demonstrated in the older age group except that there was also a gender difference (P = 0.014) in BMI. The correlation coefficients between CRF and fatness were generally low.To determine whether aerobic fitness and fatness were independently associated with resting BP, multiple regression analyses were conducted (Table 3). Fatness (P < 0.0005) and fitness (P = 0.001) were independent predictors of SBP in adolescent girls, with the association with fatness being stronger than that with fitness. Fatness was the only significant predictor (P < 0.0005) of SBP and DBP in the adolescent boys. In the younger age group, fatness was the only significant predictor of both SBP and DBP in boys and of SBP in girls. Both fitness and fatness were not shown to be significantly associated with DBP in the younger girls.TABLE 3 Fitness and fatness as predictors of SBP and DBP among participants (n = 3243).Results of the hierarchical multiple regression assessing the ability of CRF and BMI to predict resting SBP and DBP after controlling for the confounding variables (age, postexercise SBP and DBP) in girls are presented in Table 4. In children, the covariates (age, SBP1, SBP5, and SBP10) explained 21% of the variance in SBP in step 1. The addition of CRF and BMI in step 2 increased the total variance explained by the model cumulatively to 23%, indicating that CRF and BMI explained an additional variance of only 2% (P < 0.0005) after controlling for the covariates. SBP5 was the only significant predictor. The model for DBP (P < 0.0005) explained 74%, with only 1% contribution from CRF and BMI. In the adolescent girls, the SBP model explained 52% of the variance in SBP (P < 0.0005), with CRF and BMI contributing nothing. In the case of DBP, the whole model explained 93% of the variation with CRF and BMI again contributing nothing. Details of the results are shown in Table 4. Boys’ results are presented in Table 5. In the children, the whole model explained 51% of the variation in SBP with no contribution from CRF and BMI. Regarding DBP, the whole model explained 74% of the variance, with only 1% contribution from CRF and BMI (P < 0.0005). In the adolescent group, the whole model explained 36% of the variance in SBP (P < 0.0005), with only 1% contribution from CRF and BMI. Regarding DBP, the whole model explained 77% of the variance (P < 0.0005), with CRF and BMI contributing only 3%. Details of the results can be found in Table 5. The results in Tables 4 and 5 clearly show that the recovery BP was more important than fitness and fatness in predicting resting SBP and DBP. In all cases, fitness and fatness contributed only between 1% and 3% of the variance in BP after controlling for the confounding variables. Although the contribution of fitness and fatness was minimal, even then, fatness was more important than fitness in predicting the outcome variables.TABLE 4 Relationship between fitness and fatness in a generalized linear models of SBP and DBP in girls (n = 322).TABLE 5 Relationship between fitness and fatness in a generalized linear models of SBP and DBP in boys (n = 338).Results of the logistic regression analyses assessing the effect of CRF and BMI on the outcome variables showed that, in general, only fatness and age displayed significant effect, which was greater in girls than in boys. Models in the younger and older age groups were adjusted for age. In girls, the SBP model was not significant in the younger (P = 0.58) age group but significant in the older group (P < 0.0005). The model for risk of diastolic HTN in the young girls was not significant (P = 0.705). In adolescent girls, both age (OR = 1.3, 95% confidence interval [CI] = 1.2–1.5, P < 0.0005) and fatness (OR = 1.9, 95% CI = 1.1–3.3) were positively associated with the risk of systolic HTN. Regarding the risk of diastolic HTN, the model was not significant (P = 0.079). Results in the young boys indicated nonsignificant models for both risk of systolic HTN (P = 0.364) and risk of diastolic HTN (P = 0.189). Regarding the older boys, only the model for systolic HTN was significant (P < 0.001), and only age (OR = 1.3, 95% CI = 1.16–1.56, P < 0.0005) was positively associated with the dependent variable. The model for diastolic HTN in adolescent boys was not significant (P = 0.176).To further assess the effect of fitness and fatness in combination on BP, participants were categorized into four fit/fat groups and the results are presented in Table 6. The proportions of children within these categories were 85.4%, 12.0%, 2.4%, and 0.2% for fit–low fat, unfit–low fat, fit–high fat, and unfit–high fat, respectively. Corresponding values for the adolescents were 54.6%, 40.8%, 2.5%, and 2.0%. Among the children, there were no significant group differences for SBP (P < 0.48), DBP (P = 0.77), and MAP (P = 0.63) in the combined group. There were no significant (P > 0.05) group differences in the gender-specific analysis. Among the adolescents, significant group differences were noted in SBP (P = 0.017), DBP (P = 0.032), and MAP (P = 0.007) for the combined group. The only differences were between the extreme groups (fit–low fat vs unfit–high fat) for all variables. As in the children, there were no significant (P > 0.05) group differences in the gender-specific analysis in SBP, DBP, and MAP.TABLE 6 Differences in hemodynamic variables according to fatness/fitness groups (n = 3243).DISCUSSIONIn recent times, evidence from both cross-sectional and longitudinal studies in the Western societies has demonstrated that overweight and low-fit youth exhibit higher BP than their lean and fit counterparts (23,36). Although HTN is emerging as an increasingly important health issue in sub-Saharan Africa, even among youth (1), the importance of fitness and fatness in the development of HTN has not been properly investigated among African children and adolescents, especially in Nigeria.The important findings from this study include the following: First, the prevalence of risk for systolic HTN and diastolic HTN is comparable with rates reported for youth from developed and developing countries (25), and it is higher in the older than in the younger age group. Second, the correlations of fitness with fatness and both with SBP and DBP among participants were generally weak. Both fitness and fatness were shown to be independent predictors of resting BP among the participants. However, fatness was generally related more to the dependent variables than fitness in both age groups and gender. The relationship of fatness to the dependent variables is stronger in the adolescents than in the children. In all cases, the relationships were stronger in boys than in girls. Third, the combined contribution of fitness and fatness in predicting resting BP in this study was very small (R2 = 1%–3%), but postexercise BP (R2 = 23%–93%) was shown to be the major determinants of participants’ resting BP. Finally, both SBP and DBP scores varied by fit–fat groups with the fit–low-fat group demonstrating the most favorable BP values compared with the unfit–high fat counterpart with the least favorable BP profile.The prevalence of at risk of HTN of 8.7% in children and 16.7% in adolescents noted in this study is remarkably lower than the 12.5% in boys and 21.2% in girls reported for 10- to 15-yr-old black South African youth by Schutte et al. (as cited by Monyeki and Kemper [25]). But the prevalence of 3.2% in boys and 12.2% in girls reported by Matge et al. (as cited in Monyeki and Kemper [25]) for rural South black African children age between 6 and 13 yr is lower than the rate observed in the present study.In the present study, both fitness and fatness are weakly associated with both SBP and DBP in both age groups. This result may be partly due to the low prevalence of overweight in our sample. The greater proportion of normotensive relative to hypertensive study participants is another possibility. This speculation is supported by findings from a meta-analysis in adults (12). Another factor may be ethnicity because it has been observed that the correlation between fatness and BP is greater in white than in African-American black population (14). It has also been reported that, in general, the correlation among fitness, fatness, and CVD risk factors are low to moderate among samples of children and adolescents with normal weight (9). In a study involving Northern Irish adolescents (4), the correlations between fitness and CVD risk factors ranged between r = 0.01–0.16 and r = 0.12–0.26 for fatness and CVD risk factors. These values are similar to those noted in the present study. Although the associations between the independent and dependent variables are generally weak, the link is still important in health terms.Our results show that both fatness and fitness were independently and particularly associated with SBP and, to some extent, DBP in both age groups and genders. The relationship of fatness with the dependent variables is stronger in adolescents than children and in boys than in girls. The relationship is also stronger with SBP than with DBP. These findings are in agreement with previous studies in adolescents (4,23). These investigators, using white subjects (Irish and Portuguese adolescents), found both fitness and fatness to be independently associated with CVD risk factors, including BP, and found the relationship of fatness to the dependent variables to be stronger than that with fitness. Our finding of a stronger relationship of fatness with the dependent variables in boys rather than girls is concordant with that of Boreham et al. (4). Several studies in youth (4,23,29) reported that, when the associations between fitness and CVD risk factors were adjusted for fatness, the relationship became nonsignificant. Our results in the adolescent group are at odds with these observations but consistent with data from the Amsterdam Growth and Health Longitudinal Study, which investigated the contributions of fatness, fitness, and lifestyle to the development of metabolic syndrome from adolescence to young adulthood (13). In the Amsterdam Growth and Health Longitudinal Study, fatness and fitness were found to be independent predictors of metabolic syndrome, and when fatness was further adjusted for fitness or fitness was adjusted for fatness, although the relationships were reduced, they remained significant in all cases. In the present study, the relationship between fitness and BP in the adolescent group remained significant even after adjustment for fatness (data not shown). This finding clearly shows that the negative association between fitness and BP is not mediated by fatness alone. It should also be highlighted that differences in sedentary behavior, dietary habits, ethnicity, and other social and cultural factors may play a part (5,14,26).Our results showed that the joint contribution of fitness and fatness to resting BP was very small (1%–2%) in both age groups. The major determinants of resting BP were the postexercise SBP and DBP. In total, both the recovery SBP and DBP explained between 21% and 93% of the variance in the outcome variables. This result has important health implications because it has been established that exaggerated BP response and delayed recovery in BP after exercise in otherwise normotensive subjects are associated with two to three times greater risk of future development of HTN, greater prevalence of left ventricular hypertrophy, higher systemic vascular resistance, and endothelial dysfunction (30,31,33). Some of the factors that have been proposed for these conditions include: overweight and obesity (24), low fitness (24), increased sympathetic nervous activity with high plasma norepinephrine concentration, increased stroke volume and vascular resistance, elevated low-density lipoprotein cholesterol, insulin resistance, and genetic susceptibility to HTN (16,24). Therefore, interventions to prevent and manage pediatric HTN should, in addition to reducing weight and improving fitness, also emphasize the importance of a diet low in sodium and high in fruits and vegetables, fiber, and low-fat dairy; reduce sedentary behavior; and encourage positive healthy lifestyles among youth. This is because all these factors are also known to reduce the chance of HTN (26).To the best of our knowledge, the interaction of fitness and fatness has not been investigated in African youth. Results from the present study clearly demonstrate that resting BP levels varied by clinical cut points of fitness and fatness category. Specifically, high levels of fitness resulted in lower resting BP values, especially SBP and DBP within fatness categories, and the differences were more pronounced among the overweight groups. These findings are in support of previous studies in children and adolescents (8,10,29). In a study involving 9-yr-old Norwegian children, Resaland et al. (29) found that the unfit and overweight group had significantly higher CVD risk factor score than the fit normal-weight group. Similar findings were documented in other studies in youth (8,10). Our results show that adolescent boys and girls with low fat and high fitness have better BP profiles than their counterparts in high fat unfit group. Although not significant, a similar tendency was observed between participants in high-fat and high-fitness groups and high-fat–unfit group. This beneficial effect of fitness on high-fat level has been demonstrated in previous studies in youth (10,23) and adults (32). This finding suggests that high levels of CRF irrespective of fatness level have beneficial effect on health across the lifespan. Our results, especially in the adolescent group, indicate that, within fatness categories, scores of fitness were similar particularly at the low-fat categories (Table 6). This implies that fatness may have a stronger association with BP than fitness in this age group. For instance, in the adolescent group, fat boys displayed a 1.9-fold increased risk of systolic HTN relative to peers with low fat. Data from the Australian Health and Fitness Survey (10) and other populations of youth (8,29) have reported similar findings.Findings from this study have demonstrated that the deleterious effects of low aerobic fitness and high fatness on resting BP levels are more clearly observed in boys than girls. On the basis of our results and those of others, it may be reasonable to believe that both fitness and fatness are important risk factors that independently contribute to the development of HTN. Evidence from our study and others should serve as a strong stimulus to devise effective public health strategies to ameliorate HTN in youth by improving fitness and reducing fatness. However, longitudinal studies are needed to clarify the extent to which the relationship between fitness and HTN is mediated by fatness. The cross-sectional design is one of the limitations of this study because the cause-and-effect relationship cannot be confirmed and information on the sequence of risk factor development is lacking. Another limitation of this study is the noninclusion of sexual maturity because this variable is known to influence fitness test results among children and youth (29). One of the strengths of this study was the use of health-related cut points for estimated CRF and body fatness. This approach clearly indicated that participants with high CRF and low fat have lower BP values than their less fit and overweight counterparts.In conclusion, both fitness and fatness are independently associated with resting BP in Nigerian youth. The relationship between fatness and BP is stronger in the adolescents than in children. In all cases, the relationship was stronger in boys than in girls. The combined contribution of fitness and fatness in predicting resting BP is very low, but postexercise SBP and DBP were the major determinants of the dependent variables. 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