Influencia de la música y su momento de aplicación en el rendimiento y en las variables psicofisiológicas durante una contrarreloj de 5 km / Influence of music and its moments of application on performance and psychophysiological parameters during a 5km time trial

Objetivo. El propósito de este estudio fue verificar la influencia de la música introducida en diferentes momentos en una contrarreloj de ciclismo de 5 km sobre las variables psicofisiológicas. Método. Diez ciclistas entrenados participaron en este estudio (24 ± 1 años; 73,5 ± 10,4 kg, 180 ± 12 cm). Los participantes realizaron la contrarreloj de ciclismo de 5 km en 3 condiciones diferentes: música durante el precalentamiento, música durante el protocolo y control. Durante todas las condiciones fue evaluado el tiempo, la potencia, la frecuencia cardíaca y la percepción subjetiva de esfuerzo, y el estado de humor fue evaluado con el cuestionario BRUMS. Después de la estadística descriptiva, la normalidad de los datos fue confirmada por el test de Shapiro-Wilk. La media de rendimiento, el rendimiento a cada 500 m, percepción subjetiva de esfuerzo a cada 1.000 m y el estado de humor fueron comparados con la ANOVA de 2 factores para medidas repetidas (momento x condición). El nivel de significancia fue fijado en p < 0,05. Una estadística paralela fue utilizada para encontrar la menor variación de valor de todas las variables y de esta forma verificar la posibilidad de que el efecto sea trivial, benéfico o perjudicial. Resultados. Ninguna de las variables presentó diferencia entre los grupos (p > 0,05), pero existe una posibilidad de que su percepción subjetiva de esfuerzo sea pequeña cuando el individuo escucha música durante (90%) o antes (93%) del test en comparación con el test de condición de control. Conclusiones. Nuestros resultados mostraron que con independencia del momento de aplicación (por ejemplo, antes o durante el ejercicio), la música no afectó al rendimiento y las variables psicofisiológicas durante una contrarreloj de ciclismo de 5 km(AU)

Objective. The purpose of this study was to verify the influence of music introduced in different moments in a 5-km time-trial cycling (TT5KM) on psychophysical variables. Methods. Ten trained cyclists participated in this study (24 ± 1 years; 73.5 ± 10.4 kg; 180 ± 12 cm). The participants performed the TT5KM in three distinct conditions: music during warm-up (MW), music during the protocol (MP) and control (C). During all conditions the time (T), power output (W), heart rate (HR) and rating of perceived exertion (RPE) was evaluated and the mood state was assessed with the BRUMS questionnaire. After descriptive statistics, data normality was confirmed using the Shapiro-Wilk's test. Mean performance, performance at each 500m, RPE at each 1000m and mood state were compared with ANOVA two way for repeated measures (moment x condition). The significance level was set at p<0.05. A parallel statistic was used to find the smallest worthwhile change of all variables to verify the possibility of the effect to be trivial, beneficial or prejudicial. Results. None of the variables showed any difference between groups (p>0.05), but there is a possibility of RPE to be smaller when the subject listen music during (90%) or before (93%) the test compared with control condition. Conclusion. Our results showed that regardless the time of application (i.e., before or during exercise), music did not affect performance and psychophysiological parameters during the TT5KM(AU)

The relationship between rating of perceived exertion and muscle activity during exhaustive constant-load cycling.

The aims of this study were to verify the relationship between rating of perceived exertion (RPE) and electromyography (EMG) increases during exhaustive constant-load cycling bouts and, to compare and to correlate the power outputs corresponding to perceived exertion threshold (PET) and neuromuscular fatigue threshold (NFT). 11 men completed 3-4 different exhaustive constant-load cycling bouts on a cycle ergometer, being RPE and EMG measured throughout the bouts. The linear regression of the RPEslope and EMGslope against the power output identified the PET and NFT intensity, respectively. There was a significant relationship between RPEslope and EMGslope (R(2)=0.69; P<0.01). However, the linearity of RPEslope (R(2)=0.93±0.07) was significantly higher (P<0.001) than EMGslope (R(2)=0.63±0.25). In addition, the RPEslope and EMGslope were related to time to exhaustion (r=-0.59 and r=-0.60; P<0.001). There was no significant difference (P=0.42) between PET (201.5±27.9W) and NFT (210.3±22.6W) and they were significantly correlated (r=0.78; P=0.005). Therefore, the RPE and EMG increases during exhaustive constant-load cycling bouts are related and, PET and NFT intensities are similar and closely associated.

Comparison of electromyography fatigue threshold in lower limb muscles in trained cyclists and untrained non-cyclists.

The purpose of this study was to identify and compare the Electromyographic Fatigue Threshold (EMG(FT)) determined in the Vastus Lateralis (VL), Rectus Femoris (RF), Biceps Femoris (BF), Semitendinosus (ST) and Tibialis Anterior (TA) during stationary cycling in trained cyclists and non-cyclists. Using a cycle ergometer, 13 cyclists (28.4 +/- 6.9 years; 70.3 +/- 13 kg; 176.1 +/- 8.5 cm) and 11 non-cyclists (25.8 +/- 4 years; 73 +/- 9.1 kg; 175 +/- 6.4 cm), performed a maximum incremental test (ITmax) (90 rpm) to determine the (EMG(FT)). Maximal power output (W(PEAK)) reached by cyclists was higher than for non-cyclists (372.6 W and 248.9 W respectively) (P < 0.01). For the five muscles analyzed in cyclists, EMG(FT) occurred at 85.7% of cases in the VL, 92.9% in RE 78.6% in BE 78.6% in ST and 50% in TA, while in the non-cyclists group, this occurrence was 100% to muscle VL, 100% to RF, 92.6% to BF, 78.6% to ST, and 78.6% to TA. Analyzing the percentage corresponding to the power at EMG(FT) in relation to W(PEAK) reached, no differences between groups were observed for RF, BF and ST, however VL and TA, as well as the mean from all muscles were lower for cyclists than non-cyclists (P < 0.05). The present results showed that EMG(FT) is more easily identified in RF and VL muscles for both groups, and it may be an interesting method to evaluate the adaptive responses from aerobic and anaerobic metabolisms during cycling training programs.

The efficiency of pedaling and the muscular recruitment are improved with increase of the cadence in cyclists and non-cyclists.

The objective of this study was to compare the efficiency of pedaling (EP) and the electromyographic activity (EMG) between cyclists and non-cyclists during cycling in different cadences. Using a cyclosimulator, 12 cyclists (26.5 +/- 4.5 years; 68.2 +/- 10.5 kg; 175.6 +/- 8.2 cm) and 9 non-cyclists (25.1 +/- 4.3 years; 72.6 +/- 9.8 kg; 174.6 +/- 6.2 cm), performed a maximum incremental test (ITmax), and subsequently, two constant load tests (Tconst) in different cadences (60 and 90 rpm) at the intensity of the electromyographic fatigue threshold (EMGth) determined in ITmax. Before the Tconst, the subjects performed a maximum isometric voluntary contraction (MIVC) for the normalization of the EMG data of Tconst. During Tconst, the EMG of the studied muscles was recorded, as well as the EP Although there was a trend of higher values in all occasions for the cyclists, there were no statistical differences in EP and the EMG when compared in a same cadence between groups. However, when the EMG is compared in different cadences in the same group, there was a significant increase (p < 0.05) in the muscles that work during the recovery phase with the increase in cadence, in both groups, being more evident in the cyclists. In conclusion, the hypothesis that cyclists had better technique than non-cyclists was not confirmed statistically. However, it was found that the increase in cadence improves the EP and the recruitment in both groups.