Background: Carbohydrate (CHO) mouth rinse has been used as an ergogenic strategy due to its central effect; however, the effects of this intervention during short-duration high-intensity exercises are not fully understood. Purpose: To investigate the effect of CHO mouth rinse on time to exhaustion in a short-duration high-intensity exercise performed on a treadmill. Methods: A randomized double-blind, placebo-controlled, crossover study was conducted with 10 (24.1 [4.3] y) recreationally active male runners. The protocol consisted of a warm-up at 65% of VO2max for 5 min followed by 3 min passive rest. At the end of this rest period, the individuals performed their mouth rinse either with CHO (maltodextrin, 6%) or with placebo (industrialized noncaloric juice with the same taste). Immediately after mouth rinse, the subjects ran at velocity equivalent to 100% of individual VO2max until voluntary exhaustion. The perceived effort was obtained through a Borg scale. Blood lactate was quantified before and after the protocol, and heart rate was evaluated during the protocol. Results: No difference was found (P = .90) in time to exhaustion between placebo (193.9 [46.5] s) and CHO mouth rinse (195.1 [51.8] s). Blood lactate, heart rate, and perception of effort increased in both groups, but with no differences (all variables, P > .05) between groups. Conclusion: The findings showed that a preexercise single-CHO mouth rinse was ineffective to improve running time to exhaustion at velocity equivalent to 100% VO2max on a treadmill in recreationally active male runners.
Luana T. Rossato, Camila T.M. Fernandes, Públio F. Vieira, Flávia M.S. de Branco, Paula C. Nahas, Guilherme M. Puga, and Erick P. de Oliveira
Jaqueline P. Batista, Igor M. Mariano, Tállita C.F. Souza, Juliene G. Costa, Jéssica S. Giolo, Nádia C. Cheik, Foued S. Espindola, Sarah Everman, and Guilherme M. Puga
The aim of this study was to compare the hemodynamic and salivary responses after mat Pilates, aerobics, resistance exercises, and control. A total of 16 normotensive postmenopausal women performed: Pilates, 10 floor exercises; aerobics, 35 min on a treadmill (60–70% of heart rate reserve); resistance exercises, 60% of one-repetition maximum; and control, no physical exercise. Blood pressure and heart rate variability were evaluated at rest and 60 min after the intervention. Saliva samples were collected at rest, immediately after, and 30 and 60 min after exercise for analysis of nitrite concentration and total proteins. Systolic blood pressure, diastolic blood pressure, and mean blood pressure area under the curve were lower (p < .05) after both aerobic and resistance exercises sessions but not after the Pilates session when compared with the control session. Nitrite concentrations in saliva were higher 60 min after the end of all exercise sessions. Heart rate variability was higher after the resistance exercise. Aerobic and resistance exercises were capable of decreasing arterial blood pressure after acute exercise.