A adolescência é um período fundamental para a aquisição da massa óssea. Em adolescentes atletas, o pico de massa óssea pode apresentar maior incremento, em virtude do estresse mecânico imposto aos ossos pelo exercício físico praticado. O objetivo desta revisão foi investigar o papel do treinamento esportivo vigoroso e precoce sobre a saúde óssea de atletas adolescentes. Através da revisão da literatura científica, envolvendo adolescentes atletas de diferentes modalidades e de ambos os sexos, é possível inferir que a densidade mineral óssea é potencializada pelos exercícios, quando grupos de atletas são comparados com grupos de controle. Entretanto, muito se discute na literatura quanto à recomendação da intensidade adequada da prescrição de exercício físico para população adolescente, uma vez que, caso o treinamento se torne muito extenuante, os benefícios gerados pela atividade sobre a saúde dos ossos podem ser minimizados ou anulados. Embora muita controvérsia ainda envolva o tema, independente do tipo de esporte praticado, o aumento de intensidade do treinamento deve ser razoável e coerente com as metas, sendo enfatizado treinamento seguro e eficaz para cada uma das faixas de idade e momentos da maturação biológica, independente dos calendários competitivos.

Bone turnover is affected by exercise throughout the lifespan, especially during childhood and adolescence. The objective of this study was to investigate the impact of different sports on total and regional bone mineral density in male Brazilian adolescent athletes. Forty-six adolescents aged 10-18 years participated in the study: 12 swimmers, 10 tennis players, 10 soccer players, and 14 sedentary individuals. The athletes had engaged in physical activities for more than 10 h per week in the previous 6 months. Bone mineral density of the lumbar spine (L1-L4), left proximal femur region, and whole body was evaluated by dual-energy X-ray absorptiometry. Results showed higher mean values in the proximal femur region of tennis and soccer players (1.02 ± 0.18; 0.96 ± 0.16, respectively) than swimmers and controls (0.91 ± 0.14 and 0.87 ± 0.06, respectively) (P < 0.05). In relation to the impact of sporting activities based on bone age determination, we observed significant differences in bone mineral density at all evaluated sites at the end of puberty (16-18 years) compared with 10-12 years, with increases of 78% in the lumbar spine, 47% in the proximal femur, and 38% in the whole body.

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BackgroundLow-dose combined oral contraceptives (COCs) can interfere with bone mass acquisition during adolescence. This study aimed to evaluate bone mineral density (BMD) and bone mineral content (BMC) in female adolescents taking a standard low-dose COC (ethinylestradiol 20 μg/desogestrel 150 μg) over a 1-year period and to compare their data with those of healthy adolescents from the same age group not taking COCs.MethodsThis was a non-randomized parallel-control study with a 1-year follow-up. Sixty-seven adolescents aged from 12 to 19 years, divided into COC users (n = 41) taking 20 μg ethinylestradiol/150 μg desogestrel and COC non-user controls (n = 26), were evaluated by bone densitometry examinations at baseline and after 12 months. Comparisons between the groups at the study onset were performed using the Mann–Whitney test with the significance level fixed at 5% or p < 0.05. Comparisons between the groups at the study onset and after 12 months were based on variations in the median percentages for bone mass variables.ResultsThe COC users presented with low bone mass acquisition in the lumbar spine, and had BMD and BMC median variations of 2.07% and +1.57%, respectively, between the measurements at baseline and 12 months. The control group had median variations of +12.16% and +16.84% for BMD and BMC, respectively, over the same period. The total body BMD and BMC showed similar evolutions during the study in both groups. Statistical significance (p < 0.05) was seen for the BMC percentage variation between COC users and non-users.ConclusionsUse of a low-dose COC (ethinylestradiol 20 μg/desogestrel 150 μg) was associated with lower bone mass acquisition in adolescents during the study period.Trial registrationRegistry Number, RBR-5h9b3c.

SummaryBackgroundAging is associated with changes in cardiac structure and function that are associated with left ventricular diastolic dysfunction. Whether diastolic functional alterations during senescence are manifestations of the intrinsic aging process or related to cardiac adaptations to a more sedentary lifestyle is still unsettled. This was a prospective study evaluating the effects of a 6-month combined exercise training period on functional capacity and diastolic function in sedentary elderly patients with controlled arterial hypertension.Material/MethodsFunctional capacity was assessed by exercise stress test and muscle strength was evaluated by the one-repetition maximum test. Cardiac structures and function were analyzed by transthoracic echocardiography.ResultsFifteen patients, 68±8 years old, completed the training program. Exercise training significantly improved physical capacity (distance walked: 551±92 vs. 630±153 m, P<0.05; work load: 7.2±1.7 vs. 8.5±3.0 METs, P<0.05) and upper and lower extremity muscle strength (P<0.001). Arterial blood pressure significantly decreased after training (systolic blood pressure: 134±9 vs. 128±8 mmHg; diastolic blood pressure: 82±7 vs. 77±6 mmHg; P<0.05). Cardiac structures and left and right systolic and diastolic function did not change after combined training (P>0.05).ConclusionsCombined and supervised training for a 6-month period increases physical capacity and muscle strength in elderly patients with controlled arterial hypertension without changing resting left ventricular diastolic function.