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.

Listening to music in the first, but not the last 1.5 km of a 5-km running trial alters pacing strategy and improves performance.

We examined the effects of listening to music on attentional focus, rating of perceived exertion (RPE), pacing strategy and performance during a simulated 5-km running race. 15 participants performed 2 controlled trials to establish their best baseline time, followed by 2 counterbalanced experimental trials during which they listened to music during the first (M start) or the last (M finish) 1.5 km. The mean running velocity during the first 1.5 km was significantly higher in M start than in the fastest control condition (p<0.05), but there was no difference in velocity between conditions during the last 1.5 km (p>0.05). The faster first 1.5 m in M start was accompanied by a reduction in associative thoughts compared with the fastest control condition. There were no significant differences in RPE between conditions (p>0.05). These results suggest that listening to music at the beginning of a trial may draw the attentional focus away from internal sensations of fatigue to thoughts about the external environment. However, along with the reduction in associative thoughts and the increase in running velocity while listening to music, the RPE increased linearly and similarly under all conditions, suggesting that the change in velocity throughout the race may be to maintain the same rate of RPE increase.

Aerobic profile of climbers during maximal arm test.

This study compared measurements of upper body aerobic fitness in elite (EC; n=7) and intermediate rock climbers (IC; n=7), and a control group (C; n=7). Subjects underwent an upper limb incremental test on hand cycle ergometer, with increments of 23 W · min(-1), until exhaustion. Ventilation (VE) data were smoothed to 10 s averages and plotted against time for the visual determination of the first (VT1) and second (VT2) ventilatory thresholds. Peak power output was not different among groups [EC=130.9 (±11.8) W; IC=122.1 (±28.4) W; C=115.4 (±15.1) W], but time to exhaustion was significantly higher in EC than IC and C. VO(2 PEAK) was significantly higher in EC [36.8 (±5.7) mL.kg(-1).min(-1)] and IC [35.5 (±5.2) mL.kg(-1).min(-1)] than C [28.8 (±5.0) mL.kg(-1).min(-1)], but there was no difference between EC and IC. VT1 was significantly higher in EC than C [EC=69.0 (±9.4) W; IC=62.4 (±13.0) W; C=52.1 (±11.8) W], but no significant difference was observed in VT2 [EC=103.5 (±18.8) W; IC=92.0 (±22.0) W; C=85.6 (±19.7) W]. These results show that elite indoor rock climbers elicit higher aerobic fitness profile than control subjects when measured with an upper body test.

Predicting MAOD using only a supramaximal exhaustive test.

The objective of this study was to propose an alternative method (MAOD(ALT)) to estimate the maximal accumulated oxygen deficit (MAOD) using only one supramaximal exhaustive test. Nine participants performed the following tests: (a) a maximal incremental exercise test, (b) six submaximal constant workload tests, and (c) a supramaximal constant workload test. Traditional MAOD was determined by calculating the difference between predicted O(2) demand and accumulated O(2) uptake during the supramaximal test. MAOD(ALT) was established by summing the fast component of excess post-exercise oxygen consumption and the O(2) equivalent for energy provided by blood lactate accumulation, both of which were measured during the supramaximal test. There was no significant difference between MAOD (2.82+/-0.45 L) and MAOD(ALT) (2.77+/-0.37 L) (P=0.60). The correlation between MAOD and MAOD(ALT) was also high (r=0.78; P=0.014). These data indicate that the MAOD(ALT) can be used to estimate the MAOD.

Visão interdisciplinar na lombalgia crônica, causada por tensão muscular / Interdisciplinary vision in chronic low back pain caused for muscle tension

Este estudo realizado no LAPES (Laboratório de Psicologia do Esporte – CENESP / UFMG) e no BIOCINE (Laboratório de Biomecânica e Cinesiologia do UNI/ BH) teve como objetivo analisar a visão de médicos, fisioterapeutas e psicólogos do esporte, sobre a lombalgia crônica inespecífica originada de tensões musculares, baseada na classificação de ARENA e BLANCHARD1 (1996). Estes profissionais responderam um questionário denominado de “Questionário do Tratamento Interdisciplinar da Dor Crônica” (Q-TID). Os resultados apontam que a maioria destes profissionais concordou que os tratamentos interdisciplinares são mais eficazes do que as terapias isoladas no tratamento deste tipo de lombalgia. Destaca-se que médicos acreditam que psicólogos não sejam tão eficientes neste tipo de tratamento, quando comparados com o grupo de psicólogos e fisioterapeutas entrevistados.

This study, which has taken place at LAPES (Laboratório de Psicologia do Esporte – CENESP / UFMG) and at the BIOCINE (Laboratório de Biomecânica e Cinesiologia do UNI/BH) had as a primary goal the analysis of doctors, physiotherapists and sport psychologists’ view about the chronic low back pain unspecific caused for muscle tension based on the classification of ARENA and BLANCHARD1. The professionals answered a questionnaire denominated of “Questionnaire of Interdisciplinary Treatment Chronic Pain” (Q- TID). According to the results, the majority of those professionals agreed that interdisciplinary treatments are more efficient in treating permanent low back pain than isolated therapies, although doctors believe that psychologists are not so efficient as doctors and physiotherapists in this matter.