11 research outputs found

    Comparable endocrine and neuromuscular adaptations to variable vs. constant gravity-dependent resistance training among young women.

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    BACKGROUND:Variable resistance has been shown to induce greater total work and muscle activation when compared to constant resistance. However, little is known regarding the effects of chronic exposure to variable resistance training in comparison with constant resistance training. The aim of the present study was therefore to examine the effects of chain-loaded variable and constant gravity-dependent resistance training on resting hormonal and neuromuscular adaptations. METHODS:Young women were randomly assigned to variable resistance training (VRT; n = 12; age, 23.75 ± 3.64 years; and BMI, 26.80 ± 4.21 kg m-2), constant resistance training (CRT; n = 12; age, 23.58 ± 3.84 years; BMI, 25.25 ± 3.84 kg m-2), or control (Con; n = 12; age, 23.50 ± 2.93 years; BMI, 27.12 ± 12 kg m-2) groups. CRT performed 8-week total-body free-weight training three times per week with moderate-to-high intensity (65-80% 1RM; periodized). VRT was the same as CRT but included variable resistance via chains (15% of total load). Resting serum samples were taken before and after the 8-week intervention for GH, IGF-1, cortisol, myostatin, and follistatin analyses. RESULTS:Both VRT and CRT groups displayed moderate-to-large significant increases in GH (197.1%; ES = 0.78 vs. 229.9%; ES = 1.55), IGF-1 (82.3%; ES = 1.87 vs. 66%; ES = 1.66), and follistatin (58.8%; ES = 0.80 vs. 49.15%; ES = 0.80) and decreases in cortisol (- 19.9%; ES = - 1.34 vs. - 17.1%; ES = - 1.05) and myostatin (- 26.9%; ES = - 0.78 vs. - 23.2%; ES = - 0.82). Also, VRT and CRT resulted in large significant increases in bench press (30.54%; ES = 1.45 vs. 25.08%; ES = 1.12) and squat (30.63%; ES = 1.28 vs. 24.81%; ES = 1.21) strength, with no differences between groups. CONCLUSIONS:Implementing chain-loaded VRT into a periodized resistance training program can be an effective alternative to constant loading during free-weight RT among untrained young women

    Preference and torque asymmetry for elbow joint Preferência e assimetria de torque na articulação do cotovelo

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    Extensively unilateral recruitment for daily activities may determine performance asymmetries in favor of the preferred side eliciting functional adaptation. Our study evaluated asymmetries in elbow torque output between preferred and non-preferred limbs. Eighteen subjects performed maximal elbow flexor and extensor isometric contractions at five different elbow joint angles (0º, 30º, 60º, 90º, 120º) and five different angular velocities (60, 120, 180, 240, 300º.s-1) on an isokinetic dynamometer. Higher flexor torque in favor of preferred arm was observed at 90º of flexion (p<0.05), which also corresponded to the highest torque produced (p<0.05). The fact that joint angle influenced torque asymmetries, whereas angular velocity did not, suggest that the observed asymmetry is likely related to preferential recruitment of elbow flexors at a 90º joint angle for daily tasks requiring high levels of force production. Muscle functional adaptation to frequent stimuli at this joint angle in healthy subjects may explain these results.<br>O frequente recrutamento unilateral de membros superiores pode determinar assimetrias de desempenho em favor do lado preferido, resultando em adaptação funcional. Assimetrias no torque gerado pelos músculos do cotovelo entre o membro preferido e não-preferido foram avaliadas. Dezoito sujeitos realizaram contrações máximas de flexo-extensão do cotovelo em cinco ângulos articulares (0º, 30º, 60º, 90º, 120º) e cinco velocidades angulares (60, 120, 180, 240, 300º.s-1) em um dinamômetro isocinético. Torque flexor mais elevado em favor do lado preferido foi encontrado no ângulo de 90º (p<0,05), que também correspondeu ao ângulo de maior torque (p<0,05). O fato de o ângulo articular determinar assimetrias no torque (enquanto a velocidade angular não) sugere que o recrutamento preferencial dos flexores do cotovelo em um ângulo de 90º nas tarefas da vida diária que requerem força elevada é responsável pela assimetria. Adaptação funcional a estímulos frequentes nesse ângulo articular pode explicar esses resultados em sujeitos saudáveis

    Mortality and morbidity in adult craniopharyngioma.

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    A craniopharyngioma (CP) is an embryonic malformation of the sellar and parasellar region. The annual incidence is 0.5-2.0 cases/million/year and approximately 60 % of CP are seen in adulthood. Craniopharyngiomas have the highest mortality of all pituitary tumors. Typical initial manifestations at diagnosis in adults are visual disturbances, hypopituitarism and symptoms of elevated intracranial pressure. The long-term morbidity is substantial with hypopituitarism, increased cardiovascular risk, hypothalamic damage, visual and neurological deficits, reduced bone health, and reduction in quality of life and cognitive function. Therapy of choice is surgery, followed by cranial radiotherapy in about half of the patients. The standardised overall mortality rate varies 2.88-9.28 in cohort studies. Patients with CP have a 3-19 fold higher cardiovascular mortality in comparison to the general population. Women with CP have an even higher risk
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