Energy cost and physiological responses during upper body exercise with different postures / Gasto energético y respuestas fisiológicas durante el ejercicio de miembros superiores en diferentes posturas / Custo energético e respostas fisiológicas durante exercício de membros superiores realizado em diferentes posturas

Objective. The physiological and energy demand responses to upper body aerobic exercises performed with different postures are not well known. The aim of the present study was to compare energy cost and physiological responses to upper body aerobic exercises performed with different postures. Method. Eight physically active males (>1 year active), untrained in upper body aerobic exercises, with 28.2 ± 5.7 years, ht 173.7 ± 7.4 cm, body mass 74.1 ± 11.4 kg, VO2Peak 30.2 ± 2.09 ml/kg/min and Body Mass Index 24.4 ± 2.5 kg/m2 performed a preliminary maximal test and two upper body aerobic exercises 30-min sessions in different days. Results. Metabolic and hemodynamic responses to upper body aerobic exercises performed in sit-position and vertical-position were compared. The vertical-position trial showed greater total energy cost (14.3%; p = 0.01), higher lipid catabolism (p = 0.001) and a higher double product (p = 0.04), when compared to the sit-position trial. Conclusion. The upper body aerobic exercises performed in vertical-position induces a higher energetic demand and cardiovascular load than in sit-position (AU)

Objetivo. Poco se conoce sobre la influencia de la variación de la postura sobre las respuestas fisiológicas y el gasto energético durante ejercicios con miembros superiores. El objetivo de este estudio fue comparar las respuestas fisiológicas durante ejercicios con miembros superiores realizados en diferentes posturas. Método. Ocho hombres físicamente activos (>1 año), no practicantes de ejercicio con miembros superiores, con 28.2 ± 5.7 años de edad, 173.7 ± 7.4 cm de talla, 74.1 ± 11.4 kg de masa corporal, VO2Pico de 30.2 ± 2.09 ml/kg/min e índice de masa corporal de 24.4 ± 2.5 kg/m2, fueron sometidos a un test máximo preliminar y a 2 sesiones de ejercicios con miembros superiores de 30 min de duración, en días distintos. Resultados. Las respuestas metabólicas y hemodinámicas, en la postura de sentado y vertical, fueron comparadas. La sesión de ejercicio con miembros superiores realizado en postura vertical generó mayor gasto energético total (14.3%; p = 0.01), mayor catabolismo lipídico (p = 0.001) y mayor doble producto (p = 0.04), en comparación con la sesión realizada en postura sentado. Conclusiones. El ejercicio con miembros superiores realizados en postura vertical eleva el gasto energético y la sobrecarga cardiovascular, en comparación con ejercicios con miembros superiores en postura sentado (AU)

Objetivo. As respostas fisiológicas e de custo energético durante exercícios aeróbios de membros superiores realizados em diferentes posturas não são bem conhecidas. O objetivo do presente estudo foi comparar o custo energético e as respostas fisiológicas durante exercícios aeróbios de membros superiores realizados em diferentes posturas. Método. Oito homens fisicamente ativos e não praticantes de exercícios aeróbios de membros superiores, com 28.2 ± 5.7 anos de idade, 173.7 ± 7.4 cm de estatura, 74.1 ± 11.4 kg de massa corporal, VO2Pico de 30.2 ± 2.09 ml/kg/min e Índice de Massa Corporal de 24.4 ± 2.5 kg/m2, foram submetidos a um teste máximo preliminar e a 2 sessões de exercícios aeróbios de membros superiores com duração de 30 min, em dias distintos. Resultados. Respostas metabólicas e hemodinâmicas obtidas nas posturas sentada e verticalizada foram comparadas. A sessão de exercícios aeróbios de membros superiores realizado na postura verticalizada gerou maior gasto energético total (14.3%; p = 0.01), maior catabolismo lipídico (p = 0.001) e maior duplo produto (p = 0.04), quando comparado com a sessão postura sentada. Conclusões. O exercícios aeróbio de membros superiores realizado em postura verticalizada eleva o custo energético e a sobrecarga cardiovascular, quando comparado com oexercício aeróbio de membros superiores em postura sentada (AU)

Effect of pre-exercise carbohydrate availability on fat oxidation and energy expenditure after a high-intensity exercise

The aim of this study was to test the hypothesis that reduced pre-exercise carbohydrate (CHO) availability potentiates fat oxidation after an exhaustive high-intensity exercise bout. Eight physically active men underwent a high-intensity exercise (∼95% V̇O2max) until exhaustion under low or high pre-exercise CHO availability. The protocol to manipulate pre-exercise CHO availability consisted of a 90-min cycling bout at ∼70% V̇O2max + 6 × 1-min at 125% V̇O2max with 1-min rest, followed by 48 h under a low- (10% CHO, low-CHO availability) or high-CHO diet (80% CHO, high-CHO availability). Time to exhaustion was shorter and energy expenditure (EE) lower during the high-intensity exercise in low- compared to high-CHO availability (8.6±0.8 and 11.4±1.6 min, and 499±209 and 677±343 kJ, respectively, P<0.05). Post-exercise EE was similar between low- and high-CHO availability (425±147 and 348±54 kJ, respectively, P>0.05), but post-exercise fat oxidation was significantly higher (P<0.05) in low- (7,830±1,864 mg) than in high-CHO availability (6,264±1,763 mg). The total EE (i.e., exercise EE plus post-exercise EE) was similar between low- and high-CHO availability (924±264 and 1,026±340 kJ, respectively, P>0.05). These results suggest that a single bout of high-intensity exercise performed under low-CHO availability increased post-exercise fat oxidation, and even with shorter exercise duration, both post-exercise EE and total EE were not impaired.

High-CHO diet increases post-exercise oxygen consumption after a supramaximal exercise bout

We investigated if carbohydrate (CHO) availability could affect the excess post-exercise oxygen consumption (EPOC) after a single supramaximal exercise bout. Five physically active men cycled at 115% of peak oxygen uptake (V̇O2 peak) until exhaustion with low or high pre-exercise CHO availability. The endogenous CHO stores were manipulated by performing a glycogen-depletion exercise protocol 48 h before the trial, followed by 48 h consuming either a low- (10% CHO) or a high-CHO (80% CHO) diet regime. Compared to the low-CHO diet, the high-CHO diet increased time to exhaustion (3.0±0.6 min vs 4.4±0.6, respectively, P=0.01) and the total O2 consumption during the exercise (6.9±0.9 L and 11.3±2.1, respectively, P=0.01). This was accompanied by a higher EPOC magnitude (4.6±1.8 L vs 6.2±2.8, respectively, P=0.03) and a greater total O2 consumption throughout the session (exercise+recovery: 11.5±2.5 L vs 17.5±4.2, respectively, P=0.01). These results suggest that a single bout of supramaximal exercise performed with high CHO availability increases both exercise and post-exercise energy expenditure.