Emg Signal Spectral Analysis Of Superficial Quadriceps Muscles During Constant Load Submaximal Cycling Exercise [análise Espectral Do Sinal Emg Dos Músculos Superficiais Do Quadríceps Durante Exercício Submáximo De Carga Constante No Cicloergômetro]

The objective of this study was to investigate possible differences in the EMG signal spectral analysis of the superficial quadriceps muscles, using the techniques short-time Fourier transform (STFT) and continues Wavelet (CWT) db4 type during constant load submaximal cycling exercise. Fourteen male subjects, healthy and physically active (25.8 ± 3.3 years, 82.1 ± 7.3 kg, 181.3 ± 5.5 cm) were submitted to constant load submaximal test (Tcons) with exercise intensity corresponding to 80% of maximum load until voluntary exhaustion. The EMG of the vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) of the right leg were recorded throughout the period of the Tcons to obtain the parameters: median frequency (MF), fatigue index EMG (FIslp) and variance of MF. The results showed no statistically significant differences for the variables MF, FIslp and variance of MF in any of the muscles examined in different time periods, when comparing STFT and CWT (P> 0.05). Thus, our findings suggest the use of both analytical techniques in constant load submaximal cycling exercise when the target is to quantify muscle fatigue with EMG spectral indicators.222211220Barria, E.A., Jagadeesh, J.M., Multiresolution estimation of motion using the wavelet transform Proceedings (1994) Spie, 2303 (2), pp. 542-553. , LondonBeck, T.W., Housh, T.J., Johnson, G.O., Weir, J.P., Cramer, J.T., Coburn, J.W., Malek, M.H., Comparison of Fourier and wavelet transform procedures for examining the mechanomyographic and electromyographic frequency domain responses during fatiguing isokinetic muscle actions of the biceps brachii (2005) Journal of Electromyography and Kinesiology, 15 (2), pp. 190-199. , DOI 10.1016/j.jelekin.2004.08.007, PII S105064110400077XBigland-Ritchie, B., Rice, C.L., Garland, S.J., Walsh, M.L., Task-dependent factors in fatigue of human voluntary contractions (1995) Fatigue: Neural and Muscular Mechanisms, pp. 361-380. , GANDEVIA, S.C. et al. 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SIAMDe Luca, C.J., The use of surface electromyography in biomechanics (1997) Journal of Applied Biomechanics, 13 (2), pp. 135-163Flanders, M., Choosing a wavelet for single-trial EMG (2002) Journal of Neuroscience Methods, 116 (2), pp. 165-177. , DOI 10.1016/S0165-0270(02)00038-9, PII S0165027002000389Hermens, H.J., Freriks, B., Disselhorstklug, C., Rau, G., Development of recommendations for SEMG sensors and sensor placement procedures (2000) Journal of Electromyography and Kinesiology, 10 (5), pp. 361-374. , OxfordHostens, I., Seghers, J., Spaepen, A., Ramon, H., Validation of the wavelet spectral estimation technique in Biceps Brachii and Brachioradialis fatigue assessment during prolonged low-level static and dynamic contractions (2004) Journal of Electromyography and Kinesiology, 14 (2), pp. 205-215. , DOI 10.1016/S1050-6411(03)00101-9Hug, F., Laplaud, D., Lucia, A., Grelot, L., A comparison of visual and mathematical detection of the electromyographic threshold during incremental pedaling exercise: A pilot study (2006) Journal of Strength and Conditioning Research, 20 (3), pp. 704-708. , DOI 10.1519/R-17405.1Hummel, A., Laubli, T., Pozzo, M., Schenk, P., Spillmann, S., Klipstein, A., Relationship between perceived exertion and mean power frequency of the EMG signal from the upper trapezius muscle during isometric shoulder elevation (2005) European Journal of Applied Physiology, 95 (4), pp. 321-326. , DOI 10.1007/s00421-005-0014-7Hunter, A.M., St Clair Gibson, A., Lambert, M.I., Nobbs, L., Noakes, T.D., Effects of supramaximal exercise on the electromyographic signal (2003) British Journal of Sports Medicine, 37 (4), pp. 296-299. , DOI 10.1136/bjsm.37.4.296Karlsson, S., Yu, J., Akay, M., Time-frequency analysis of myoelectric signals during dynamic contractions: A comparative study (2000) IEEE Transactions on Biomedical Engineering, 47 (2), pp. 228-238. , DOI 10.1109/10.821766, PII S0018929400008867Knaflitz, M., Bonato, P., Time-frequency methods applied to muscle fatigue assessment during dynamic contractions (1999) Journal of Electromyography and Kinesiology, 9 (5), pp. 337-350. , DOI 10.1016/S1050-6411(99)00009-7, PII S1050641199000097Kumar, D.K., Pah, N.D., Bradley, A., Wavelet Analysis of Surface Electromyography to Determine Muscle Fatigue (2003) IEEE Transactions on Neural Systems and Rehabilitation Engineering, 11 (4), pp. 400-406. , DOI 10.1109/TNSRE.2003.819901Laubli, T., Hermens, H., Sjogaard, G., Neuromuscular assessment of the elderly worker, NEW: A multidisciplinary European research project (2006) European Journal of Applied Physiology, 96 (2), pp. 107-109. , DOI 10.1007/s00421-005-0045-0MacIsaac, D., Parker, P.A., Scott, R.N., The short-time Fourier transform and muscle fatigue assessment in dynamic contractions (2001) Journal of Electromyography and Kinesiology, 11 (6), pp. 439-449. , DOI 10.1016/S1050-6411(01)00021-9, PII S1050641101000219Merletti, R., Rainoldi, A., Farina, D., Surface electromyography for noninvasive characterization of muscle (2001) Exercise and Sport Sciences Reviews, 29 (1), pp. 20-25Ng, J.K.-F., Richardson, C.A., Kippers, V., Parnianpour, M., Bui, B.H., Clinical applications of power spectral analysis of electromyographic investigations in muscle function (1996) Manual Therapy, 1 (2), pp. 99-103. , DOI 10.1054/math.1996.0257Nybo, L., Nielsen, B., Perceived exertion is associated with an altered brain activity during exercise with progressive hyperthermia (2001) Journal of Applied Physiology, 91 (5), pp. 2017-2023Oliveira, A.D.E.S., Goncalves, M., EMG amplitude and frequency parameters of muscular activity: Effect of resistance training based on electromyographic fatigue threshold (2009) Journal of Electromyography and Kinesiology, 19 (2), pp. 295-303. , OxfordSo, R.C., Ng, J.K., Lam, R.W., Lo, C.K., Ng, G.Y., EMG Wavelet analysis of quadriceps muscle during repeated knee extension movement (2009) Medicine and Science in Sports and Exercise, 41 (4), pp. 788-796. , HagerstownSparto, P.J., Parnianpour, M., Barria, E.A., Jagadeesh, J.M., Wavelet analysis of electromyography for back muscle fatigue detection during isokinetic constant-torque exertions (1999) Spine, 24 (17), pp. 1791-1798. , DOI 10.1097/00007632-199909010-00008Troiano, A., Naddeo, F., Sosso, E., Camarota, G., Merletti, R., Mesin, L., Assessment of force and fatigue in isometric contractions of the upper trapezius muscle by surface EMG signal and perceived exertion scale (2008) Gait and Posture, 28 (2), pp. 179-186. , DOI 10.1016/j.gaitpost.2008.04.002, PII S0966636208000994Vitor-Costa, M., Pereira, L.A., Oliveira, R.S., Pedro, R.E., Camata, T.V., Abrao, T., Brunetto, M.A., Altimari, L.R., Fourier and Wavelet spectral analysis of EMG signals in maximal constant load dynamic exercise (2010) Conference Proceedings IEEE Engineering in Medicine and Biology Society, 1 (1), pp. 4622-4625. , Buenos Aire

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 (EMG th) 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.496-7311319Candotti, C.T., Effective force and economy of triathletes and cyclists (2007) Sports Biomech, 6 (1), pp. 31-43Chapman, A., Do differences in muscle recruitment between novice and elite cyclists reflect different movement patterns or less skilled muscle recruitment? (2007) J. Sci. Med. Sport., , doi: 10.1016/j.jsams. 2007.08.012Chapman, A.R., Patterns of leg muscle recruitment vary between novice and highly trained cyclists (2007) J. Electromyogr. Kinesiol., , doi: 10.1016/j.jelekin. 2005.12.007(2006) Users Guide, Spinscan Pedal Stroke Analyzer, pp. 24-26. , COMPUTRAINER COACHING SOFTWAREDavis, R.R., Hull, M.L., Measurement of pedal loading in bicycling: Analysis and results (1981) J. Biomech., 14 (12), pp. 857-872Denadai, B.S., Ruas, V.D., De, A., Figueira, T.R., Efeito da cadência de pedalada sobre as respostas metabolica e cardiovascular durante o exercício incremental e de carga constante em indivíduos ativos. Revista Brasileira de Mediana (2005) Esporte, 11 (5), pp. 286-290Faria, E.W., Parker, D.L., Faria, I.E., The science of cycling: Physiology and training - Part 1 (2005) Sports Medicine, 35 (4), pp. 285-312Faria, E.W., Parker, D.L., Faria, I.E., The science of cycling: Factors affecting performance - Part 2 (2005) Sports Medicine, 35 (4), pp. 313-337Gregor, B.J., Wheeler, J.B., Biomechanical factors associated with shoe/pedal interfaces: Implications for injury (1994) Sports Medicine, 17 (2), pp. 117-131Gregor, R.J., Biomecânica do ciclismo (2003) A Ciência Do Exercício e Dos Esportes, pp. 547-571. , GARRETT J.R, WE. and KIRKENDALL, D.T.: trad. RIDEL, C et al. Porto Alegre: ARTMEDHall, S.J., Conceitos cinéticos para a análise do movimento humano (2000) Biomecânica Básica, 3, pp. 46-65. , Trad. TARANTO, G. Rio de Janeiro: GUANABARA KOOGAN, capHanon, C., Thepaut-Mathieu, C., Vandewalle, H., Determination of muscular fatigue in elite runners (2005) Eur. J. 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Applied Physiol., 90, pp. 643-646Hull, M.L., Jorge, M., A method for biomechanical analysis of bicycle pedalling (1985) J. Biomech., 18 (9), pp. 631-644Korff, T., Effect of pedaling technique on mechanical effectiveness and efficiency in cyclists (2007) Med Sci. Sports Exerc., 39 (6), pp. 991-995Lucía, A., Analysis of the aerobic-anaerobic transition in elite cyclists during incremental exercise with the use of electromyography (1999) Br. J. Sports Med., 33, pp. 178-185Lucía, A., Hoyos, J., Chicharro, J.L., Preferred pedalling cadence in professional cycling (2001) Med. Sci. Sports Exec., 33 (8), pp. 1361-1366Neptune, R.R., Herzog, W., The association between negative muscle work and pedaling rate (1999) J. Biomech., 32, pp. 1021-1026Neptune, R., Hull, M.L., A theoretical analysis of preferred pedaling rate selection in endurance cycling (1999) J. Biomech., 32, pp. 409-415Neptune, R.R., Kautz, S.A., Hull, M.L., The effect of pedalling rate on coordination in cycling (1997) J. 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Spectral Analysis Of Electromyographic Signal In Supramaximal Effort In Cycle Ergometer Using Fourier And Wavelet Transforms: A Comparative Study

Objective. The objective of this study was to compare these methods Fourier (STFT) and Wavelet (WT) transforms to assess muscle fatigue during supramaximal exercise. Methods. Twenty five subjects of both genders (13 men, age = 28.2 ± 2.7 years and 12 women, age = 23.2 ± 2.7 years) performed the Wingate test, during which the electromyographic responses of the superficial muscles of the quadriceps were examined. For analysis we used the STFT and WT transforms, which provided the following variables: median frequency (MF), slope and variance. Results. The results showed no differences (P > 0.05) in MF and slope. However, there were differences for the variance between the analysis (P < 0.05). Conclusion. It seems that both analyzes provide the same physiological parameters, however, the WT transform shows less variance between the results. © 2012 Revista Andaluza de Medicina del Deporte.524852Enoka, R.M., Stuart, D.G., Neurobiology of muscle fatigue (1992) J Appl Physiol., 72, pp. 1631-1648Nybo, L., Nielsen, B., Perceived exertion is associated with an altered brain activity during exercise with progressive hyperthermia (2001) J Appl Physiol., 91, pp. 2017-2023Hummel, A., Laubli, T., Pozzo, M., Schenk, P., Spillmann, S., Klipstein, A., Relationship between perceived exertion and mean power frequency of the EMG signal from the upper trapezius muscle during isometric shoulder elevation (2005) Eur J Appl Physiol., 95, pp. 321-326Laubli, T., Hermens, H., Sjogaard, G., Neuromuscular assessment of the elderly worker, New: A multidisciplinary European research project (2006) Eur J Appl Physiol., 96, pp. 107-109Troiano, A., Naddeo, F., Sosso, E., Camarota, G., Merletti, R., Mesin, L., Assessment of force and fatigue in isometric contractions of the upper trapezius muscle by surface EMG signal and perceived exertion scale (2008) Gait Posture., 28, pp. 179-186Oliveira, S., Gonçalves, M., EMG amplitude and frequency parameters of muscular activity: Effect of resistance training based on electromyographic fatigue threshold (2009) J Electromyogr Kinesiol., 19, pp. 295-303Ng, J.K., Richardson, C.A., Kippers, V., Parnianpour, M., Bui, B.H., Clinical applications of power spectral analysis of electromyographic investigations in muscle function (1996) Man Ther., 1, pp. 99-103Knaflitz, M., Bonato, P., Time-frequency methods applied to muscle fatigue assessment during dynamic contractions (1999) J Electromyogr Kinesiol., 9, pp. 337-350Bonato, P., Roy, S.H., Knaflitz, M., De Luca, C.J., Time-frequency parameters of the surface myoelectric signal for assessing muscle fatigue during cyclic dynamic contractions (2001) IEEE Trans Biomed Eng., 48, pp. 745-753Beck, T.W., Housh, T.J., Johnson, G.O., Weir, J.P., Cramer, J.T., Coburn, J.W., Comparison of fourier and wavelet transform procedures for examining the mechanomyographic and electromyographic frequency domain responses during fatiguing isokinetic muscle actions of the biceps brachii (2005) J Electromyogr Kinesiol., 15, pp. 190-199Dantas, J.L., Camata, T.V., Brunetto, M.A., Moraes, A.C., Abrão, T., Altimari, L.R., Fourier and wavelet spectral analysis of EMG signals in isometric and dynamic maximal effort exercise (2010) Conference Proceedings (IEEE Engineering in Medicine and Biology Society Conf), 1, pp. 5979-5982Camata, T.V., Dantas, J.L., Abrão, T., Brunetto, M.A., Moraes, A.C., Altimari, L.R., Fourier and wavelet spectral analysis of EMG signals in supramaximal constant load dynamic exercise (2010) Conference Proceedings (IEEE Engineering in Medicine and Biology Society Conf), 1, pp. 1364-1367Vitor-Costa, M., Pereira, L.A., Oliveira, R.S., Pedro, R.E., Camata, T.V., Abrão, T., Fourier and wavelet spectral analysis of EMG signals in maximal constant load dynamic exercise (2010) Conference Proceedings (IEEE Engineering in Medicine and Biology Society Conf), 1, pp. 4622-4625Von Tscharner, V., Goepfert, B., Estimation of the interplay between groups of fast and slow muscle fibers of the tibialis anterior and gastrocnemius muscle while running (2006) J Electromyogr Kinesiol., 16, pp. 188-197Sparto, P.J., Parnianpour, M., Barria, E.A., Jagadeesh, J.M., Wavelet analysis of electromyography for back muscle fatigue detection during isokinetic constant-torque exertions (1999) Spine (Phila Pa 1976), 24, pp. 1791-1798Hostens, I., Seghers, J., Spaepen, A., Ramon, H., Validation of the wavelet spectral estimation technique in biceps brachii and brachioradialis fatigue assessment during prolonged low-level static and dynamic contractions (2004) J Electromyogr Kinesiol., 14, pp. 205-215Da Silva, R.A., Lariviere, C., Arsenault, A.B., Nadeau, S., Plamondon, A., The comparison of Wavelet-and Fourier-based electromyographic indices of back muscle fatigue during dynamic contractions: Validity and reliability results (2008) Electromyogr Clin Neurophysiol., 48, pp. 147-162Karlsson, S., Yu, J., Akay, M., Time-frequency analysis of myoelectric signals during dynamic contractions: A comparative study (2000) IEEE Trans Biomed Eng., 47, pp. 228-238Ponorac, N., Matavulj, A., Rajkovaca, Z., Kovacevic, P., The assessment of anaerobic capacity in athletes of various sports (2007) Med Pregl., 60, pp. 427-430Bar-Or, O., The Wingate anaerobic test. 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Association Between The Electromyographic Fatigue Threshold And Ventilatory Threshold

The objective of this study is to verify the coincidence between the occurrence of the electromyographic fatigue threshold (EMGth) and the ventilatory threshold (Vth) in an incremental test in the cyclosimulator, as well as to compare the calculation of the RMS from the EMG signal using different time windows. Thirteen male cyclists (73.7 ± 12.4 kg and 174.3 ± 6.2 cm) performed a ramp incremental test (TI) in a cyclosimulator until voluntary exhaustion. Before the start of each TI subjects had the active bipolar electrodes placed over the superficial muscles of the quadriceps femoris (QF) of the right leg: rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL). The paired student's t test, pearson's correlation coefficient and the analysis method described by Bland and Altman for the determination of the concordance level were used for statistical analysis. The significance level adopted was P &lt; 0.05. Although no significant differences were found between Vth and the EMG th calculated from windows of 2, 5, 10, 30 and 60 seconds in the studied muscles, it is suggested that the EMGth values determined from the calculation of the RMS curve with windows of 5 and 10 seconds seem to be more appropriate for the calculation of the RMS curve and determination of EMGth from visual inspection.496-7305310Basmajian, J.V., DeLuca, C.J., (1985) Muscles Alive: Their Functions Revealed by Electromyography, , Williams & WilkinsBland, J.M., Altman, D.G., Statistical methods for assessing agreement between two methods of clinical measurement (1986) Lancet, 1, pp. 307-310(2006) Encyclopedia of Medical Devices and Instrumentation, pp. 98-109. , DELUCA, C.J.: Electromyography. In: WEBSTER, J.G. (Ed.). John Wiley PublisherGordon, C.C., Chumlea, W.C., Roche, A.F., Stature, recumbent length, and weight (1988) Anthropometric Standardization Reference Manual, , T. LOHMAN, G., ROCHE, A.F. and MARTORELL, F., eds. Champaign: Human KineticsHelal, J.N., Guezennec, C.Y., Goubel, F., The aerobic-anaerobic transition: Re-examination of the threshold concept including an electromyographic approach (1987) Eur. J. Appl. Physiol., 56, pp. 643-649Hermens, H.J., Freriks, B., Disselhorst-Klug, C., Rau, G., Development of recommendations for SEMG sensors and sensor placement procedures (2000) J. Electromyogr. Kinesiol., 10 (5), pp. 361-374Hug, F., Laplaud, D., Savin, B., Grelot, L., Occurrence of electromyographic and ventilatory thresholds in professional road cyclists (2003) Eur. J. Appl. Physiol., 90 (5-6), pp. 643-646Hug, F., Raucher, M., Kipson, N., Jammes, Y., EMG signs of neuromuscular fatigue related to the ventilatory threshold during cycling exercise (2003) Clin. Physiol. Funct. Imaging., 23 (4), pp. 208-214Hug, F., Faucher, M., Marqueste, T., Guillot, C.H., Kipson, N., Jammes, Y., Electromyographic signs of neuromuscular fatigue are concomitant with further increase in ventilation during static handgrip (2004) Clin. Physiol. Funct. Imaging., 24 (1), pp. 25-32Hug, F., Laplaud, D., Lucia, A., Grelot, L.A., Comparison of visual and mathematical detection of the electromyographic threshold during incremental pedaling exercise: A pilot study (2006) Journal of Strength and Conditioning Research, 20 (3), pp. 704-708Merletti, R., Knaflitz, M., DeLuca, C.J., Electrically evoked myoelectric signals (1992) Crit. Rev. Biomed. Eng., 19 (4), pp. 293-340McLellan, T.M., Ventilatory and plasma lactate response with different exercise protocols: A comparison of methods (1985) Int. J. Sports Med., 6 (1), pp. 30-35Moritani, T., (1980) Anaerobic Threshold Determination by Electromyography (Doctoral Dissertation), , University of Southerns CaliforniaNagata, A., Muro, M., Moritani, T., Yoshida, T., Anaerobic threshold determination by blood lactate and myoelectric signals (1981) Jpn. J. Physiol., 31 (4), pp. 585-597Viitasalo, J.T., Luhtanen, P., Rahkila, P., Rusko, H., Electromyographic activity related to aerobic and anaerobic threshold in ergometer bicycling (1985) Acta. Physiol. Scand., 124 (2), pp. 287-29