Unfit Adolescents Research Articles

Visceral adiposity index, fitness and clustered cardiovascular disease risk in adolescents.

Clustering of cardiovascular disease (CVD) risk factors have been observed in children and adolescents, but its association with visceral adiposity index (VAI) and cardiorespiratory fitness (CRF) in adolescents has rarely been studied. This study determines the independent associations of VAI and CRF with the clustering of cardiovascular disease risk (CVDr) among Nigerian adolescents. Adolescents from specific secondary schools in Kogi East, North Central Nigeria participated in the study. A cross-sectional sample of 403 adolescents (202 boys and 201 girls) aged 11 years - 19 years were evaluated for VAI, CRF and CVDr. Using identified risk factors, a clustered CVDr score was generated. The association between VAI, CRF and clustered CVDr was evaluated using regression models that controlled for age, gender and maturity status. Fitness was negatively associated with CVDr (β= -0.268,p 0.001), while VAI was positively correlated with CVDr (β= 0.379,p 0.001). After CRF or VAI adjustment, the independent association with the dependent variable remained significant. The odds of an adolescent with elevated VAI being at risk of CVD was 4.7 times higher than his peers. Unfit adolescents were 2.1 times more likely to develop CVDr. Both VAI and CRF were independently associated with the clustering of CVDr in Nigerian adolescents. The findings suggest that health promotion efforts focusing on healthy diet and aerobic-type physical activity programmes should be encouraged among the youth to reduce the risk of CVD.Contribution:This study shows that improving visceral adipose tissue and fitness may lower CVD risk factors in adolescents, which is significant for public health.

Could Physical Fitness Be Considered as a Protective Social Factor Associated with Bridging the Cognitive Gap Related to School Vulnerability in Adolescents? The Cogni-Action Project.

The first aim was to compare differences between school vulnerability groups, fitness levels, and their combination in adolescent cognitive performance. The second aim was to determine the mediation role of fitness in the association between school vulnerability and cognitive performance. A total of 912 Chilean adolescents aged 10–14 years participated in this study. The school vulnerability index (SVI) assigned by the Chilean Government was categorized into high-, mid-, or low-SVI. Adolescents were classified as fit or unfit according to their global fitness z-score computed from their cardiorespiratory (CRF), muscular (MF), and speed/agility fitness (SAF) adjusted for age and sex. A global cognitive score was estimated through eight tasks based on a neurocognitive battery. Covariance and mediation analyses were performed, adjusted for sex, schools, body mass index, and peak high velocity. Independent analyses showed that the higher SVI, the lower the cognitive performance (F(6,905) = 18.5; p < 0.001). Conversely, fit adolescents presented a higher cognitive performance than their unfit peers (F(5,906) = 8.93; p < 0.001). The combined analysis found cognitive differences between fit and unfit adolescents in both the high- and mid-SVI levels (Cohen’s d = 0.32). No differences were found between fit participants belonging to higher SVI groups and unfit participants belonging to lower SVI groups. Mediation percentages of 9.0%, 5.6%, 7.1%, and 2.8% were observed for the global fitness score, CRF, MF, and SAF, respectively. The mediation effect was significant between low- with mid-high-SVI levels but not between mid- and high-SVI levels. These findings suggest that an adequate physical fitness level should be deemed a protective social factor associated with bridging the cognitive gap linked to school vulnerability in adolescents. This favourable influence seems to be most significant in adolescents belonging to a more adverse social background.

Low-grade inflammation and muscular fitness on insulin resistance in adolescents: Results from LabMed Physical Activity Study.

Low muscular fitness (MF) and low-grade inflammation has been linked to insulin resistance (IR). To evaluate the associations between MF and a clustered score of inflammatory biomarkers on IR and to investigate the combined impact of MF and inflammation on IR in adolescents. This is a cross-sectional analysis with 529 adolescents (267 girls) aged 12 to 18 years. Pubertal stage, socioeconomic status, adherence to the Mediterranean diet, cardiorespiratory fitness, and waist circumference were assessed. Standing long-jump and isometric handgrip dynamometry were used as indicators of MF. Continuous score of clustered inflammatory biomarkers (InflaScore) (sum of Z-scores of C-reactive protein, C3, C4, fibrinogen, and leptin) and IR (homeostasis model assessment of insulin resistance [HOMA-IR] estimated from fasting serum insulin and glucose) were assessed. HOMA-IR and fasting insulin were positively associated with InflaScore and negatively associated with MF, independently of age, sex, pubertal stage, socioeconomic status, adherence to the Mediterranean diet, cardiorespiratory fitness, and waist circumference. Adolescents classified as High InflaScore/Unfit showed significantly higher HOMA-IR when compared than those with High InflaScore/Fit and those with Low InflaScore/Fit (F(3,519) = 4.761, P < .003), after adjustments for potential confounders. Unfit adolescents with high InflaScore had the highest odds of expressing high HOMA-IR (odds ratio, OR = 2.40, 95% confidence interval [CI]: 1.2-5.6) and insulin risk (2.53 95% CI, 1.5-5.9) when compared to those of the Low InflaScore/Fit group, after adjustments for potential confounders. Higher levels of MF seem to minimize the deleterious effect of inflammation on IR.

Physical fitness as a mediator between objectively measured physical activity and clustered metabolic syndrome in children and adolescents: The UP&DOWN study

Background and aimsThe extent to which physical fitness (PF) attenuates or modifies the association between physical activity (PA) and clustered metabolic syndrome risk factors (CMetSRF) is controversial. We aimed: i) To examine the independent and combined association of objectively measured PA and PF with CMetSRF in children and adolescents; ii) To test the mediating effect of PF in the association of PA with CMetSRF. Methods and resultsA total of 226 children and 256 adolescents participated. Levels of PA (light, moderate, vigorous and moderate-to-vigorous [MVPA]) and PF were measured by accelerometry and ALPHA battery, respectively. Cardiorespiratory and muscular fitness values were combined in a global PF variable. A CMetSRF was computed by assessing the following variables: waist circumference, systolic blood pressure, high-density lipoprotein cholesterol, triglycerides and glucose. In children, the highest vigorous PA (β = −0.193; P = 0.003) and MVPA (β = −0.149; P = 0.025) were individually associated with lower CMetSRF, but these associations were not independent of global PF. In adolescents, the association of moderate (β = −0.123; P = 0.046) and MVPA (β = −0.147; P = 0.024) with CMetSRF was independent of PF. Among unfit adolescents, the higher time they spent in MVPA the lower CMetSRF levels were found (P = 0.032). ConclusionsThe results are suggestive of a full mediation of global PF in the association of MVPA and vigorous PA with CMetSRF in children. In adolescents, the association of higher moderate and MVPA with lower CMetSRF was independent of levels of PF, and mediation analyses suggest only a partial mediation of global PF in the association of MVPA with CMetSRF.

Cardiorespiratory fitness is negatively associated with metabolic risk factors independently of the adherence to a healthy dietary pattern

Background and aimCardiorespiratory fitness (CRF) and diet have been involved as significant factors towards the prevention of cardio-metabolic diseases. This study aimed to assess the impact of the combined associations of CRF and adherence to the Southern European Atlantic Diet (SEADiet) on the clustering of metabolic risk factors in adolescents. Methods and ResultsA cross-sectional school-based study was conducted on 468 adolescents aged 15-18, from the Azorean Islands, Portugal. We measured fasting glucose, insulin, total cholesterol (TC), HDL-cholesterol, triglycerides, systolic blood pressure, waits circumference and height. HOMA, TC/HDL-C ratio and waist-to-height ratio were calculated. For each of these variables, a Z-score was computed by age and sex. A metabolic risk score (MRS) was constructed by summing the Z scores of all individual risk factors. High risk was considered when the individual had ≥1SD of this score. CRF was measured with the 20 m-Shuttle-Run-Test. Adherence to SEADiet was assessed with a semi-quantitative food frequency questionnaire. Logistic regression showed that, after adjusting for potential confounders, unfit adolescents with low adherence to SEADiet had the highest odds of having MRS (OR = 9.4; 95%CI:2.6–33.3) followed by the unfit ones with high adherence to the SEADiet (OR = 6.6; 95% CI: 1.9–22.5) when compared to those who were fit and had higher adherence to SEADiet. ConclusionsUnfit adolescents showed higher odds of having high MRS, regardless of the adherence to SEADiet suggesting that high CRF may overcome the deleterious effects of low adherence to a healthy dietary pattern in adolescents.

Metabolic Syndrome and Physical Fitness in a Sample of Azorean Adolescents

Metabolic syndrome, a predecessor of cardiovascular disease and type 2 diabetes, has become prevalent in adolescents. This study aimed to estimate the prevalence of metabolic syndrome and its components and to analyze the relationship between metabolic syndrome and overall physical fitness levels in a sample of Azorean adolescents. A cross-sectional school-based study, the Azorean Physical Activity and Health Study II, was conducted on 517 adolescents (297 girls, 220 boys) aged 15-18 years old from the Azorean Islands. Body height, weight, waist circumference, and arterial blood pressure were measured according to standards. Fasting intravenous blood samples were analyzed (high-density lipoprotein cholesterol, triglycerides, and glucose). Physical fitness was assessed using five tests from Fitnessgram Test Battery 8.0: Curl-up, push-up, trunk lift, pacer, and sit-and-reach. Adolescents were then classified as being in the healthy zone or above or under the healthy zone. Metabolic syndrome was defined according to the 2007 International Diabetes Federation‘s guidelines for adolescents. The prevalence of metabolic syndrome was 5% (4.7% in girls and 5.5% in boys, P > 0.05). Waist circumference was the most prevalent component (32.9%), and hypertriglyceridemia the least (4.4%). Logistic regression analysis showed that after adjusting for pubertal stage and socioeconomic status, unfit adolescents (healthy zone criteria in <or=2 tests) were more likely [odds ratio (OR) = 3.414; 95% confidence interval (CI), 1.150-10.129] to be classified as having metabolic syndrome. The prevalence of metabolic syndrome is high in Azorean adolescents. Unfit adolescents were more likely to have metabolic syndrome than fit adolescents. Improving overall physical fitness levels and abdominal obesity reduction may be important strategies in overcoming this public health problem and its consequences.

High Numbers of Physically Unfit Adolescents

As obesity becomes an increasing problem for children and adolescents, their physical fitness is of concern. Researchers assessed a cross-sectional