Rafael Evangelista Pedro

Fourier and wavelet spectral analysis of EMG signals in supramaximal constant load dynamic exercise

Frequency domain analyses of changes in electromyographic (EMG) signals over time are frequently used to assess muscle fatigue. Fourier based approaches are typically used in these analyses, yet Fourier analysis assumes signal stationarity, which is unlikely during dynamic contractions. Wavelet based methods of signal analysis do not assume stationarity and may be more appropriate for joint time-frequency domain analysis. The purpose of this study was to compare Short-Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) in assessing muscle fatigue in maximal constant load dynamic exercise (100% Wmax). The results of this study indicate that CWT and STFT analyses give similar fatigue estimates (slope of median frequency) in maximal constant load dynamic exercise (P>0.05). However, the results of the variance was significantly lower for at least one of the muscles studied in CWT compared to STFT (P<0.05) indicating more variability in the EMG signal analysis using STFT. Thus, the stationarity assumption may not be the sole factor responsible for affecting the Fourier based estimates.

Running speeds at ventilatory threshold and maximal oxygen consumption discriminate futsal competitive level.

Abstract Pedro, RE, Milanez, VF, Boullosa, DA, and Nakamura, FY. Running speeds at ventilatory threshold and maximal oxygen consumption discriminate futsal competitive level. J Strength Cond Res 27(2): 514–518, 2013—We tested the hypothesis that maximal oxygen uptake and ventilatory threshold (VT), and their respective speeds (SV[Combining Dot Above]O2max and SVT) could discriminate the competitive level of futsal players. The outfield players of a high-level Brazilian professional futsal team (N = 9; age 22.6 ± 4.2 years; body mass 70.6 ± 6.4 kg; height 174.3 ± 6.0 cm), and a semiprofessional team (N = 11; age 17.2 ± 0.8 years; body mass 70.4 ± 6.5 kg; height 175.0 ± 4.0 cm), volunteered for participation in this study. Subsequently, they were evaluated during an incremental treadmill test for the determination of cardiorespiratory variables, SV[Combining Dot Above]O2max, and SVT. Both teams exhibited a similar body mass and V[Combining Dot Above]O2max (p = 0.542 and p = 0.427), whereas the SV[Combining Dot Above]O2max and the SVT were significantly higher in the professional team (p = 0.001 and p = 0.030, respectively). Additionally, the professional team exhibited both lower HR at VT (p = 0.046) and HRmax (p = 0.002). However, the %HRmax at VT did not differ between groups (p = 0.912). These results remained similar after adjusting for the age differences between groups (p = 0.106). It was concluded that both SV[Combining Dot Above]O2max and SVT were sensitive for detecting differences in the competitive level of futsal players, whereas V[Combining Dot Above]O2max and VT were not.

Aplicação de diferentes métodos de quantificação de cargas durante uma sessão de treinamento de karate

A percepcao subjetiva de esforco (PSE) da sessao tem se destacado dentre os metodos de quantificacao de cargas de treinamento (QCT) em algumas modalidades, sobretudo pelo seu baixo custo e facil aplicabilidade. No entanto, nao ha relatos na literatura de sua aplicacao na modalidade de karate. O objetivo deste estudo foi analisar a relacao entre o metodo PSE da sessao com BanisterTRIMP, EdwardsTL, LuciaTRIMP, StagnoTRIMP e LacTRIMP. Para tanto, oito atletas de ambos os sexos (21,6 ± 5,5 anos; 58,8 ± 13,8kg; 170,0 ± 0,11cm) realizaram uma sessao de treinamento com monitoramento constante da frequencia cardiaca (FC), coleta de amostras sanguineas a cada 10 minutos e afericao da PSE atraves da escala CR-10, 30 minutos apos o termino do treinamento, para posterior calculo dos impulsos de treinamento. Significantes correlacoes (P < 0,05) foram encontradas entre PSE da sessao e BanisterTRIMP (r = 0,79), EdwardTL (r = 0,81), LuciaTRIMP (r = 0,71), StagnoTRIMP (r = 0,71) e LacTRIMP (r = 0,91). Dessa forma, os resultados deste estudo sugerem a PSE da sessao como um metodo eficiente para a QCT em atletas de karate estilo shotokan.

Cardiac autonomic recovery after a single session of resistance exercise with and without vascular occlusion.

Abstract Okuno, NM, Pedro, RE, Leicht, AS, de Paula Ramos, S, and Nakamura, FY. Cardiac autonomic recovery after a single session of resistance exercise with and without vascular occlusion. J Strength Cond Res 28(4): 1143–1150, 2014—The aim of this study was to investigate the heart rate variability (HRV) after resistance training with and without vascular occlusion. It was hypothesized that low intensity (LI) with vascular occlusion (LIO) would elicit comparable postexercise HRV responses with that of high intensity (HI) without vascular occlusion. Nine subjects undertook 4 experimental sessions of leg press exercise on different days: (a) 1 repetition maximum (1RM) test, (b) 4 sets of 8 repetitions + 1 set until exhaustion at 80% of 1RM without vascular occlusion (HI), (c) 4 sets of 16 repetitions + 1 set until exhaustion at 40% of 1RM with vascular occlusion (LIO), and (d) 4 sets of 16 repetitions + 1 set with the number of repetitions equal to the last set of LIO but at 40% of 1RM without vascular occlusion (LI). Heart rate variability was analyzed 10 minutes, 20 minutes, 30 minutes, 1 hour, 5 hours, and 24 hours after the HI, LIO, and LI sessions. The HI session increased the heart rate (HR) and reduced the root mean square of the successive difference of R-R intervals (RMSSD) and log-transformed high-frequency (lnHF) power during prolonged recovery (HR = 5 hours; RMSSD = 30 minutes; lnHF = 1 hour) at a greater magnitude when compared with LIO and LI. Despite the same intensity of exercise for LIO and LI, the occlusion delayed the recovery of HR and HRV variables. Postexercise blood lactate concentration was moderate to strongly correlated with peak HR (r = 0.87), RMSSD (r = −0.64), and lnHF (r = −0.68). This study has demonstrated that LIO was able to reduce cardiac autonomic stress when compared with HI.

Effects of 16 Weeks of Concurrent Training on Resting Heart Rate Variability and Cardiorespiratory Fitness in People Living With HIV/AIDS Using Antiretroviral Therapy: A Randomized Clinical Trial.

Abstract Pedro, RE, Guariglia, DA, Okuno, NM, Deminice, R, Peres, SB, and Moraes, SMF. Effects of 16 weeks of concurrent training on resting heart rate variability and cardiorespiratory fitness in people living with HIV/AIDS using antiretroviral therapy: a randomized clinical trial. J Strength Cond Res 30(12): 3494–3502, 2016—The study evaluated the effects of concurrent training on resting heart rate variability (HRVrest) and cardiorespiratory fitness in people living with HIV/AIDS undergoing antiretroviral therapy (ART). Fifty-eight participants were randomized into 2 groups (control and training group); however, only 33 were analyzed. The variables studied were HRVrest indices, submaximal values of oxygen uptake (V[Combining Dot Above]O2sub) and heart rate (HR5min), peak speed (Vpeak), and peak oxygen uptake (V[Combining Dot Above]O2peak). The training group performed concurrent training (15–20 minutes of aerobic exercise plus 40 minutes of resistance exercise), 3 times per week, for 16 weeks. Posttraining V[Combining Dot Above]O2peak and Vpeak increased, and HR5min decreased. Resting heart rate variability indices did not present statistical differences posttraining; however, the magnitude-based inferences demonstrated a “possibly positive effect” for high frequency (HF) and low frequency (LF) plus high frequency (LF + HF) and a “likely positive effect” for R-Rmean posttraining. In conclusion, concurrent training was effective at improving cardiorespiratory fitness and endurance performance. Moreover, it led to probably a positive effect on HF and a likely positive effect on R-Rmean in people living with HIV/AIDS undergoing ART.

Exercise improves cytokine profile in HIV-infected people: A randomized clinical trial

Purpose Verify the effects of concurrent training on cytokines in people living with HIV under antiretroviral therapy (ART) treatment. Methods This was a blinded, parallel‐group, clinical trial, where 49 participants, divided in two groups, either control group or concurrent training group, took part in the intervention. The control group performed recreational activities and concurrent training group participated of 16‐week, 3 times per week of heart rate guided‐aerobic plus resistance training for major muscular groups. Cytokines (interleukins 4, 5, 6, 8, 10, tumor necrosis factor‐&agr;, interferon‐&ggr;, and granulocyte‐macrophage colony‐stimulating factor) were measured before and after 16‐week experimental period using flow cytometry. Results From 49 participants who took part in the intervention, 28 completed the program and had data analyzed. There was a significant interaction for IL‐8, which increased for control group: 7.1 ± 5.1 vs. 8.1 ± 6.0 and a decrease for concurrent training: 8.0 ± 4.4 vs. 5.4 ± 2.3. In addition, magnitude‐based inference showed a likely beneficial effect for the training group when compared to the control group for IL‐8, IL‐5, and IL‐10. The difference perceptual: mean and [CI 90%] between delta of difference within groups was −43.1 [−64.0 to −10.0] and ‐6.6 [−14.7 to 2.3], respectively. Conclusion Short‐term exercise is able to decrease the levels of IL‐5, IL‐8, and IL‐10 in HIV‐infected people undergoing ART. HighlightsConcurrent training was beneficial on circulating cytokines HIV‐infected people.Concurrent training decreases the pro‐inflammatory effects induced by ART.Some circulating cytokines were not changed after training in HIV‐infected people. Graphical abstract Figure. No Caption available.

Efeito temporal sobre a resposta da percepção subjetiva do esforço

INTRODUCAO: A percepcao subjetiva de esforco da sessao (PSE da sessao) e um metodo de facil aplicacao e de muita utilidade no contexto esportivo, sendo sugerido um periodo de 30 min apos a sessao de treinamento para sua avaliacao; no entanto, nao existem dados empiricos que suportem essa sugestao.OBJETIVO: Verificar a correlacao e a concordância entre a percepcao subjetiva de esforco (PSE) media reportada durante sessoes de treinamento com valores de PSE reportados 5, 15 e 30 min apos o termino das sessoes de treinamento, em atletas de basquetebol de ambos os generos.METODOS: Participaram desse estudo 11 atletas do sexo feminino e nove atletas do sexo masculino. A PSE foi avaliada atraves da escala de PSE CR-10 a cada 20 min durante a sessao de uma hora de treinamento (PSE media da sessao) e 5, 15 ou 30 min apos o termino. Dessa forma, a PSE media de cada sessao de treinamento foi comparada com os valores de PSE reportados 5, 15 e 30 min apos as sessoes.RESULTADOS: Nao houve diferenca significante da PSE media entre as tres sessoes. As maiores correlacoes foram observadas entre PSE media das sessoes 2 e 3 com a PSE reportada 15 e 30 min, apos para homens (r = 0,92 - 0,91) e mulheres (r = 0,75 - 0,82). Os maiores valores de concordância foram verificados entre a PSE media das sessoes 1 e 2 e as reportadas 15 min e 30 min apos para ambos generos.CONCLUSAO: Com base nos resultados, sugerimos que se evite reportar a PSE 5 min apos o termino da sessao. Alem disso, recomendamos reportar a PSE no minimo 15 min e, sobretudo, 30 min apos o termino da sessao.

Effect of combined training on body composition and metabolic variables in people living with HIV: A randomized clinical trial

Purpose The aim of this study was to conduct a randomized clinical trial to assess the effects of 16 weeks of combined training on body composition, lipid profile, adiponectin, C‐reactive protein (CRP), and leptin levels in people living with HIV/AIDS (PLWHA). Methods Fifty‐eight HIV‐infected individuals were randomized into a training group (T) or a control group (C). Combined training consisted of aerobic and resistance exercises performed at the same training session, applied at a frequency of three times a week for a total of 16 weeks. Waist circumference, body mass, body fat percentage (%fat), fat mass, lipid profile, adiponectin, CRP, and leptin levels were measured pre‐ and post‐training in both groups. Results Sixteen weeks of combined training decreased (P < 0.05) body fat in different body segments in PLWHA. Lipodystrophic PLWHA experienced greater reduction in body fat in the android region than non‐lipodystrophic PLWHA after combined training. Lipid profile and circulating levels of adiponectin, leptin, and CRP remained unchanged. Conclusions Sixteen weeks of combined training was effective to reduce body fat in different body segments, without altering plasma lipid and cytokine levels. HighlightsCombined training was beneficial for body composition HIV‐infected people.Combined training did not modify lipid profile and cytokines levels.Reduction of body fat was not accompanied by metabolic changes.Patients with lipodystrophy showed reduction of android fat when compared to non‐lipodystrophic. Graphical abstract Figure. No caption available.

Efecto temporal sobre la respuesta de la percepción subjetiva del esfuerzo

INTRODUCAO: A percepcao subjetiva de esforco da sessao (PSE da sessao) e um metodo de facil aplicacao e de muita utilidade no contexto esportivo, sendo sugerido um periodo de 30 min apos a sessao de treinamento para sua avaliacao; no entanto, nao existem dados empiricos que suportem essa sugestao.OBJETIVO: Verificar a correlacao e a concordância entre a percepcao subjetiva de esforco (PSE) media reportada durante sessoes de treinamento com valores de PSE reportados 5, 15 e 30 min apos o termino das sessoes de treinamento, em atletas de basquetebol de ambos os generos.METODOS: Participaram desse estudo 11 atletas do sexo feminino e nove atletas do sexo masculino. A PSE foi avaliada atraves da escala de PSE CR-10 a cada 20 min durante a sessao de uma hora de treinamento (PSE media da sessao) e 5, 15 ou 30 min apos o termino. Dessa forma, a PSE media de cada sessao de treinamento foi comparada com os valores de PSE reportados 5, 15 e 30 min apos as sessoes.RESULTADOS: Nao houve diferenca significante da PSE media entre as tres sessoes. As maiores correlacoes foram observadas entre PSE media das sessoes 2 e 3 com a PSE reportada 15 e 30 min, apos para homens (r = 0,92 - 0,91) e mulheres (r = 0,75 - 0,82). Os maiores valores de concordância foram verificados entre a PSE media das sessoes 1 e 2 e as reportadas 15 min e 30 min apos para ambos generos.CONCLUSAO: Com base nos resultados, sugerimos que se evite reportar a PSE 5 min apos o termino da sessao. Alem disso, recomendamos reportar a PSE no minimo 15 min e, sobretudo, 30 min apos o termino da sessao.

Temporal effect on the response of subjective perceived exertion

INTRODUCAO: A percepcao subjetiva de esforco da sessao (PSE da sessao) e um metodo de facil aplicacao e de muita utilidade no contexto esportivo, sendo sugerido um periodo de 30 min apos a sessao de treinamento para sua avaliacao; no entanto, nao existem dados empiricos que suportem essa sugestao.OBJETIVO: Verificar a correlacao e a concordância entre a percepcao subjetiva de esforco (PSE) media reportada durante sessoes de treinamento com valores de PSE reportados 5, 15 e 30 min apos o termino das sessoes de treinamento, em atletas de basquetebol de ambos os generos.METODOS: Participaram desse estudo 11 atletas do sexo feminino e nove atletas do sexo masculino. A PSE foi avaliada atraves da escala de PSE CR-10 a cada 20 min durante a sessao de uma hora de treinamento (PSE media da sessao) e 5, 15 ou 30 min apos o termino. Dessa forma, a PSE media de cada sessao de treinamento foi comparada com os valores de PSE reportados 5, 15 e 30 min apos as sessoes.RESULTADOS: Nao houve diferenca significante da PSE media entre as tres sessoes. As maiores correlacoes foram observadas entre PSE media das sessoes 2 e 3 com a PSE reportada 15 e 30 min, apos para homens (r = 0,92 - 0,91) e mulheres (r = 0,75 - 0,82). Os maiores valores de concordância foram verificados entre a PSE media das sessoes 1 e 2 e as reportadas 15 min e 30 min apos para ambos generos.CONCLUSAO: Com base nos resultados, sugerimos que se evite reportar a PSE 5 min apos o termino da sessao. Alem disso, recomendamos reportar a PSE no minimo 15 min e, sobretudo, 30 min apos o termino da sessao.