Different ventilatory responses to progressive maximal exercise test performed with either the arms or legs.

OBJECTIVE: This study aimed to compare respiratory responses, focusing on the time-domain variability of ventilatory components during progressive cardiopulmonary exercise tests performed on cycle or arm ergometers. METHODS: The cardiopulmonary exercise tests were conducted on twelve healthy volunteers on either a cycle ergometer or an arm ergometer following a ramp protocol. The time-domain variabilities (the standard deviations and root mean squares of the successive differences) of the minute ventilation, tidal volume and respiratory rate were calculated and normalized to the number of breaths. RESULTS: There were no significant differences in the timing of breathing throughout the exercise when the cycle and arm ergometer measurements were compared. However, the arm exercise time-domain variabilities for the minute ventilation, tidal volume and respiratory rate were significantly greater than the equivalent values obtained during leg exercise. CONCLUSION: Although the type of exercise does not influence the timing of breathing when dynamic arm and leg exercises are compared, it does influence time-domain ventilatory variability of young, healthy individuals. The mechanisms that influence ventilatory variability during exercise remain to be studied.

Estudo duplo-cego e randomizado do peeling de ácido retinoico a 5% e 10% no tratamento do melasma: avaliação clínica e impacto na qualidade de vida / Double-blind randomized study of 5% and 10% retinoic acid peels in the treatment of melasma: clinical evaluation and impact on the quality of life

Introdução: o melasma é dermatose de alta prevalência que provoca grande impacto na qualidade de vida dos pacientes. Seu tratamento é um desafio. O índice de área e gravidade do melasma - Masi, e o Melasma Quality of Life Scale - MelasQoL são instrumentos úteis na avaliação clínica e do impacto na qualidade de vida, respectivamente. Objetivo: estudar, através do Masi e MelasQoL, o efeito do peeling de ácido retinoico em pacientes portadoras de melasma, comparando as concentrações de 5 e 10%. Métodos: 30 pacientes foram randomizados e submetidos a peelings de ácido retinoico a 5% ou 10% nas semanas 0, 2, 4 e 6.As pacientes foram submetidas à avaliação clínica, através do Masi e à avaliação da qualidade de vida, através do MelasQoL, nas semanas 0 e 8. Resultados: na avaliação global dos dois grupos houve redução estatisticamente significativa de ambos os índices após os tratamentos. Quando se compararam os peelings de ácido retinoico a 5 e 10% não se observou diferença estatisticamente significativa entre as variáveis Masi e MelasQoL. Conclusões: o peeling de ácido retinóico é eficaz e seguro no tratamento do melasma, como tratamento isolado, e não há diferença da melhora quando se comparam as concentrações de 5% e 10%.

Different ventilatory responses to progressive maximal exercise test performed with either the arms or legs

OBJECTIVE: This study aimed to compare respiratory responses, focusing on the time-domain variability of ventilatory components during progressive cardiopulmonary exercise tests performed on cycle or arm ergometers. METHODS: The cardiopulmonary exercise tests were conducted on twelve healthy volunteers on either a cycle ergometer or an arm ergometer following a ramp protocol. The time-domain variabilities (the standard deviations and root mean squares of the successive differences) of the minute ventilation, tidal volume and respiratory rate were calculated and normalized to the number of breaths. RESULTS: There were no significant differences in the timing of breathing throughout the exercise when the cycle and arm ergometer measurements were compared. However, the arm exercise time-domain variabilities for the minute ventilation, tidal volume and respiratory rate were significantly greater than the equivalent values obtained during leg exercise. CONCLUSION: Although the type of exercise does not influence the timing of breathing when dynamic arm and leg exercises are compared, it does influence time-domain ventilatory variability of young, healthy individuals. The mechanisms that influence ventilatory variability during exercise remain to be studied.

The influence of a fast ramp rate on peak cardiopulmonary parameters during arm crank ergometry.

The influence of a very fast ramp rate on cardiopulmonary variables at ventilatory threshold and peak exercise during a maximal arm crank exercise test has not been extensively studied. Considering that short arm crank tests could be sufficient to achieve maximal oxygen consumption (VO2), it would be of practical interest to explore this possibility. Thus, this study aimed to analyse the influence of a fast ramp rate (20 W min⁻¹) on the cardiopulmonary responses of healthy individuals during a maximal arm crank ergometry test. Seventeen healthy individuals performed maximal cardiopulmonary exercise tests (Ultima CardiO2; Medical Graphics Corporation, St Louis, USA) in arm ergometer (Angio, LODE, Groningen, The Netherlands) following two protocols in random order: fast protocol (increment: 2 w/6 s) and slow protocol (increment: 1 w/6 s). The fast protocol was repeated 60-90 days after the 1st test to evaluate protocol reproducibility. Both protocols elicited the same peak VO2 (fast: 23.51 ± 6.00 versus slow: 23.28 ± 7.77 ml kg⁻¹ min⁻¹; P = 0.12) but peak power load in the fast ramp protocol was higher than the one in the slow ramp protocol (119 ± 43 versus. 102 ± 39 W, P < 0.001). There was no other difference in ventilatory threshold and peak exercise variables when 1st and 2nd fast protocols were compared. Fast protocol seems to be useful when healthy young individuals perform arm cardiopulmonary exercise test. The usefulness of this protocol in other populations remains to be evaluated.