Influence of the Type of Physical Training on the Physical Fitness of Army Cadets.

INTRODUCTION: Military Physical Training programs represent a constant challenge for the Armed Forces to improve body composition indices and physical fitness levels. This study aimed to verify the influence of the type of training on the physical fitness and body composition of army cadets, using 2 strategies: a sports program (Athletes group) and conventional physical training (Traditional group). MATERIALS AND METHODS: This study involved new entrant male cadets who were selected for the Athletes group (n = 243, 19.08 ± 1.23 years) or the Traditional group (n = 356, 18.89 ± 0.97 years), with assessments occurring before and after the period of training (31.4 ± 3.9 weeks). Dual-energy X-ray absorptiometry was used to measure the bone mineral content (BMC), fat mass (FM), percentage of fat mass (%FM), and lean soft tissue (LST). The physical tests evaluated the 3,000 m run (RUN), 50 m swim (SWIM), pull-ups (PULL) on the horizontal bar, push-ups (PUSH) on the ground, and abdominal flexion (SITUP). RESULTS: Time × group interaction effects were observed for BMC (P < .001), LST (P < .023), RUN (P < .001), PULL (P = .006), PUSH (P < .001), SITUP (P = .007), and SWIM (P < .001). A significant effect of time was noted for all variables analyzed in both groups, except %FM. The Athletes group achieved better results in body composition and in PULL, PUSH, RUN, and SWIM at baseline and after the training period. The Traditional group demonstrated higher relative changes (%) after the training period in the LST (P = .001), PULL (P < .001), PUSH (P < .001), SITUP (P < .004), and SWIM (P < .001) compared to the Athletes group. CONCLUSION: Both physical training programs improved body composition and physical performance.

Higher Body Fat but Similar Phase Angle Values in Patients with the Classical Form of Congenital Adrenal Hyperplasia in Comparison to a Control Group.

This study aimed to compare phase angle (PhA) and bioelectrical impedance vector analysis (BIVA) values between adult patients with congenital adrenal hyperplasia caused by 21-hydroxylase deficiency (CAH21OHD) and a control group. A total of 22 patients (15 women, 22.9 ± 3.7 years) were compared with 17 controls (11 women, 27.0 ± 2.5 years). Body composition was determined by dual-energy X-ray absorptiometry. Bioelectrical impedance was used to calculate PhA, and BIVA was performed using specific software. Student's t-test and analysis of covariance were used to compare groups. Hedges' G and partial n2 were calculated for the effect estimates. Hotelling's t2 test was used to compare the mean impedance vectors between the groups. The Mahalanobis test was used to determine the distance between confidence ellipses. Patients with CAH21OHD had a higher fat mass percentage than that of the control group (both sexes). There was no significant difference in PhA values between groups (CAH21OHD vs. control) in females (6.9° vs. 6.3°, p = 0.092) and males (8.2° vs. 8.1°, p = 0.849), after adjusting for covariates (age and height). BIVA analysis showed a significant difference in the mean impedance vectors between the female groups (T2 = 15.9, D = 1.58, p = 0.003) owing to the higher reactance/height (Δ = 8.5; p < 0.001) of the patients. The PhA did not significantly differ between the groups. Female patients had significantly higher reactance values. However, further studies are needed to determine the usefulness of bioimpedance parameters in evaluating the hydration status and cellular integrity of patients with CAH21OHD.

Effect of Physical Training on Body Composition in Brazilian Military.

The military are selected on the basis of physical standards and are regularly involved in strong physical activities, also related to particular sports training. The aims of the study were to analyze the effect of a 7-month military training program on body composition variables and the suitability of specific 'bioelectrical impedance vector analysis' (spBIVA), compared to DXA, to detect the changes in body composition. A sample of 270 male Brazilian cadets (19.1 ± 1.1 years), composed of a group practicing military physical training routine only (MT = 155) and a group involved in a specific sport training (SMT = 115), were measured by body composition assessments (evaluated by means of DXA and spBIVA) at the beginning and the end of the military routine year. The effect of training on body composition was similar in SMT and MT groups, with an increase in LST. DXA and spBIVA were correlated, with specific resistance (Rsp) and reactance (Xcsp) positively related to fat mass (FM), FM%, LST, and lean soft tissue index (LSTI), and phase angle positively related to LST and LSTI. Body composition variations due to physical training were recognized by spBIVA: the increase in muscle mass was indicated by the phase angle and Xcsp increase, and the stability of FM% was consistent with the unchanged values of Rsp. Military training produced an increase in muscle mass, but no change in FM%, independently of the sample characteristics at baseline and the practice of additional sports. SpBIVA is a suitable technique for the assessment of body composition in military people.

Bioelectrical Impedance Phase Angle and Its Determinants in Patients with Classic Congenital Adrenal Hyperplasia.

BACKGROUND: Patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH21OHD) have increased fat mass and metabolic alterations. The bioelectrical impedance phase angle (PhA) is an indicator of cellular integrity in several diseases. This study aimed to determine the influence of adiposity levels, sex, CAH21OHD, pubertal development, body composition, and treatment on the PhA of patients with CAH21OHD. METHODS: Forty girls and 30 boys with CAH21OHD aged 15.3 ± 5.8 years were evaluated. Sexual maturation was assessed by a pediatrician. The PhA was assessed using bioelectrical impedance, percentage of fat mass (% FM), and lean soft tissue (LST) with dual-energy X-ray absorptiometry. Adiposity levels were compared using % FM tertiles and body mass index (BMI). Glucocorticoid dosage was converted using hydrocortisone dose equivalent (HDE). RESULTS: No differences were found in the PhA values among the clinical form (p = 0.103), BMI (p = 0.498), and % FM (p = 0.654) groups. High PhA values were observed in boys (p = 0.011) and postpubertal (p < 0.001) patients. LST, HDE, and height in girls (r2 = 0.68, p < 0.001) and age, HDE, and FM in boys (r2 = 0.82, p < 0.001) determined the PhA variations. BMI explained 14% (p = 0.032) of the PhA variations, whereas LST, height, HDE, and FM (kg) explained 66% (p < 0.001) in the prepubertal, pubertal, and postpubertal groups, respectively. CONCLUSION: LST determined the PhA variations in girls and the postpubertal group. Age and BMI were determinants in boys and the pre- and pubertal groups, respectively.

Phase Angle is Determined by Body Composition and Cardiorespiratory Fitness in Adolescents.

The phase angle is used to evaluate nutritional status and is an indicator of cellular health. Cardiorespiratory fitness and body composition are strong indicators of health during adolescence. We aimed to evaluate if body composition and cardiorespiratory fitness have an association with phase angle among adolescents. 203 girls and 220 boys (12.8±1.3 years) were evaluated. Peak height velocity, percentage fat mass, fat-free mass, cardiorespiratory fitness, and phase angle measurements were collected. Linear regression adjusted by peak height velocity was used to verify if predictor variables were associated with phase angle among adolescents. Phase angle showed correlation with fat-free mass (girls: r=0.42 and boys: r=0.37); with percent fat mass (girls: r=0.23); and with cardiorespiratory fitness (boys: r=0.19). Linear regression showed that percentage fat mass (in girls) and cardiorespiratory fitness (in boys) had an effect of 11 and 17% in phase angle, respectively, while fat-free mass had an effect of 22 and 26% in phase angle for girls and boys, respectively. Changes in phase angle seem to be more associated with the percentage fat mass in girls, cardiorespiratory fitness in boys, and fat-free mass in both when controlled by peak height velocity.

Dual-energy x-ray absorptiometry metabolic maps to resting energy expenditure estimation, and body size dependence in Brazilian young men.

OBJECTIVES: The model most suitable for estimating resting energy expenditure (REE) using dual-energy X-ray absorptiometry (DXA) metabolic maps is not known; moreover, the applicability in individuals with different body sizes also is uncertain. The aim of this study was to test the accuracy of REE estimation from models of DXA metabolic maps with four, five, and six tissue-organ components in young men, stratified by body size. METHODS: We studied 52 young men between the ages of 18 and 29 y. Participants were clustered to small (SW; n = 32) and large (LW; n = 20) weight, and small (SWH; n = 25) and large (LWH; n = 27) weight-height. REE was measured by indirect calorimetry (REEm), and predicted from DXA metabolic maps with four (REEc1), five (REEc2) and six (REEc3) tissue-organ components. RESULTS: REEc1, REEc2, and REEc3 explained 54% (P < 0.001), 56% (P < 0.001), and 58% (P < 0.001) of REEm variance in all participants, respectively. However, REEc2 showed mean difference between REEm (P < 0.001), and REEc3 showed trends in estimating the REE (P < 0.05). In contrast, REEc1 showed limits of agreement (95%) of -248.3 to 285.8 kcal/d, 18.7 ± 136.3 kcal/d of bias, and no trends in the Bland-Altman analysis. The relationship between all predicted models and measured REE decreased in LW and LWH. CONCLUSIONS: REEc1 can be considered the best accurate model of REE estimation in Brazilian young men, providing the REE and metabolically active tissue-organ of four components. Caution should be exercised with the use of DXA metabolic maps in populations with greater weight and greater weight-height.

Effectiveness of intervention programs in schools to reduce health risk factors in adolescents: a systematic review / Efetividade de programas de intervenção escolar para reduzir fatores de risco à saúde em adolescentes: uma revisão sistemática

Abstract The aim of this study was to systematically review studies on intervention programs involving physical activity promotion and/or nutritional education to reduce health-related risk factors (overweight/obesity and metabolic profilealterations) in Brazilian adolescent students. A search was performed in the following electronic databases: Medline (PubMed), Lilacs, Embase, Scielo and Capes Thesis Database. A total of 1,568 studies were identified, of which 21 full papers were analyzed and 5 were included in the systematic review. The majority of the studies involved physical activity practice combined with nutritional education in Brazilian adolescent students and all interventions showed positive effect on reducing health-related risk factors among Brazilian adolescents.It was concluded that all studies included in this review showed positive alterations in health-related risk factors after interventions, reinforcing the importance of intervention programs to promote a healthier lifestyle and reduce health-related risk factors in adolescents.

Resumo O objetivo do estudo foi realizar uma revisão sistemática sobre os programas de intervenção, com ações de atividades físicas e/ou educação nutricional, na redução de fatores de risco à saúde (sobrepeso/obesidade e alterações no perfil metabólico), em adolescentes escolares brasileiros. Foi realizada busca nas bases de dados eletrônicas Medline (PubMed), Lilacs, Embase, Scielo e Banco de Teses da Capes. Identificaram-se 1.568 estudos e 21 textos completos foram analisados, dos quais, cinco foram incluídos na revisão. A maioria dos estudos envolveu a prática de atividades físicas combinada à educação nutricional em diferentes regiões do país e todas as intervenções mostraram efeitos positivos na redução de fatores de risco à saúde. Conclui-se que todos os estudos nesta revisão demonstraram alterações positivas após as intervenções, mesmo que não significativas estatisticamente, reforçando a importância de programas de intervenção para a promoção de uma vida mais saudável e para reduzir os fatores de risco à saúde, em adolescentes.