ANTONIO CARLOS DE MORAES
@fef.unicamp.br
FACULTY OF PHYSICAL EDUCACION
UNIVERSITY OF CAMPINAS
undergraduate, master's and doctorate degrees in Physical Education. Full professor (State University of Campinas). Has experience in the area of Physical Education (football, electromyography, training, fatigue and ergogenic resources.
EDUCATION
undergraduate, master's and doctorate degrees in Physical Education. Full professor (State University of Campinas). Has experience in the area of Physical Education (football, electromyography, training, fatigue and ergogenic resources.
RESEARCH, TEACHING, or OTHER INTERESTS
Physical Therapy, Sports Therapy and Rehabilitation
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Arthur Fernandes Gáspari, Mayni Gabriele Zaminiani, Manoela de Carvalho Vilarinho, Danilo Caruso, Patricia dos Santos Guimarães, Rafael Perlotti Piunti, Alex Itaborahy, and Antonio Carlos de Moraes
Frontiers Media SA
This study aimed to investigate recovery markers among elite climbers following the National Boulder Championship. We assessed maximum isometric hand grip strength (HS), forearm swelling (circumference), delayed soreness in forearm muscles, tiredness, and exercise readiness at several time points: pre-competition, immediately post-competition (within 4 min after their last effort), and 12, 24, 48, and 60 h post-competition. Maximum isometric hand grip strength decreased by 6.38 ± 1.32% (p = 0.006) post-12 h, returning to pre-competition values post-24 h (all p > 0.05). Forearm circumference (FC) increased 1.78 ± 1.77% (p < 0.001) post-competition, returning to pre-competition values post-12 h (all p > 0.05). Forearm pain (FP) increased post-competition (p = 0.002) and post-12 h (p < 0.001), returning to pre-competition values post-24 h (all p > 0.05). Tiredness increased post-competition (p < 0.001), post-12 h (p < 0.001), and post-24 h (p < 0.001), returning to pre-competition values post-48 h (all p > 0.05). Climbing readiness was reduced post-competition (p < 0.001), post-12 h (p < 0.001), post-24 h (p < 0.001), and post-48 h (p = 0.005), only returning to pre-competition values post-60 h (p = 0.189). Visual analysis of individual data pointed out a relatively small variability in the HS and FC markers, while FP, tiredness, and readiness exhibited larger individual variations. These findings indicate that different recovery patterns exist for the analyzed markers, suggesting that athletes may require up to 60 h after a competition to fully recover and regain their ability to face new competitive challenges.
Manoel Silva, Arthur Gáspari, João Barbieri, Danilo Caruso, Jonatas Nogueira, André Andrade, and Antônio Moraes
Springer Science and Business Media LLC
Manoel Silva, Arthur Gáspari, João Barbieri, Renato Barroso, Gabriel Figueiredo, Leonardo Motta, and Antônio Moraes
Springer Science and Business Media LLC
Juliana Altimari, Leandro Altimari, Henrique Bortolotti, Adalberto Junior, Juliano Gabardo, Cosme Buzzachera, Ariobaldo Frisselli, and Antonio Moraes
Termedia Sp. z.o.o.
The present study aimed to investigate the influence of months of birth on anthropometry, body composition, biological maturation, and motor performance in young Brazilian soccer players. Young Brazilian soccer players from the Under-13 (n = 50; 13.6 ± 0.3 years), Under-15 (n = 50; 15.5 ± 0.4 years), and Under-17 categories (n = 46; 17.7 ± 0.3 years) took part in this study. Athletes were divided according to chronological age, 1<sup>st</sup> tertile (January to April); 2<sup>nd</sup> tertile (May to August); and 3<sup>rd</sup> tertile (September to December). Anthropometry, body composition, biological maturation, and motor performance variables were evaluated for all participants. There were no differences between the U-13, U-15, and U-17 categories regarding birth tertiles (p > 0.05). Differences between the ages and birth tertiles were observed for the stature, body mass, and lean body mass (p < 0.05). Moreover, differences were found in maturational status between the ages and birth tertiles (p < 0.05). In general, U-13 players showed lower values compared to U-15 and U-17 players in tests of motor performance. In addition, there was a difference in motor performance between the birth tertiles only for RSA variables. The months of birth influenced the stature, body mass, lean body mass, and repeated sprint ability in the U-13 and U-15 categories. Thus, care should be taken during the process of talent selection, as many young players could be underestimated due to their date of birth.
Denis Fabrício Valério, Ricardo Berton, João Francisco Barbieri, Jader Calzavara, Antônio Carlos De Moraes, and Renato Barroso
Informa UK Limited
ABSTRACT The objective of the study was to investigate the effects of using lifting straps on the lat pull-down exercise on maximal strength, number of repetitions, and muscle activation. Twelve resistance-trained men participated (age 27 ± 4 years, body mass 84 ± 10 kg, height 177 ± 6 cm, resistance training experience 6.6 ± 2.4 years). All participants performed the 1RM tests and training protocols either with the lifting straps (WS) or without (WOS). Exercise sessions for both conditions (WS and WOS) consisted of 3 sets to concentric failure with a load of 70% of one repetition maximum (1RM) and rest intervals of 60 s. For the 1RM test, no difference was observed between WS and WOS conditions (96.5 ± 12.7 kg and 96.6 ± 11.9 kg, respectively). There were no differences between the WS and WOS conditions in the number of repetitions per set, total repetitions and latissimus dorsi muscle activation. In conclusion, the findings of this study demonstrate that the use of lifting straps in the lat pull-down exercise by resistance-trained individuals does not promote beneficial effect in the 1RM value, the number of repetitions performed with 70% of 1RM, and muscle activation.
Pedro R Pezarat-Correia, Pedro R Medeiros, Orlando J Fernandes, João R Vaz, Luis Silva, and Antonio Carlos Moraes
Centro Andaluz de Medicina del Deporte
Objective: To quantify and compare the electromyographic activity of 10 muscles in three pullover exercises.
 Methods: 15 healthy men, with at least two years of experience in resistance training, executed in random order six repetitions with 60% of 1 Maximum Repetition for three different pullover exercises: lying on a step with a barbell, grip 100% biacromial (E1); lying on a step with a barbell, grip 150% (E2); lying on a Swiss ball with a barbell, grip 100% (E3). Surface electromyography was recorded from the Deltoideus (Clavicular and Spinalis Pars), Pectoralis Major (Clavicular and Sternocostalis Pars), Serratus Anterior, Triceps Brachii (Long Head), Latissimus Dorsi, Infraspinatus, Rectus Abdominis, Obliquus Internus Abdominis and Transversus Abdominis. The normalized Maximum Repetition electromyographyc of each muscle was calculated for each exercise.
 Results: The most engaged muscles were Infraspinatus (51-53%) and Posterior Deltoid (49-51%). Surface electromyography activity was similar between the E1, E2 and E3 exercises.
 Conclusions: This study quantified muscular solicitation during pullover exercises performed with 60% Maximum Repetition. The muscles with higher level of activation were the Posterior Deltoid and the Infraspinatus, suggesting that pullover may be a valid option for strengthening the dynamic stabilizing muscles of shoulder joint in trained individuals. No significant differences in muscle electromyography intensity were observed when grip distance and trunk stabilization were altered, showing that these conditions do not influence muscle activation levels. However, the 1 Maximum Repetition was lower when the pullover was performed on a Swiss ball, suggesting that it is possible to obtain higher level of muscle recruitment with lower weights in unstable exercises.
João Francisco Barbieri, Arthur Fernandes Gáspari, Cassia Lopes Teodoro, Leonardo Motta, Luz Albany Arcila Castaño, Romulo Bertuzzi, Celene Fernandes Bernades, Mara Patrícia Traina Chacon-Mikahil, and Antonio Carlos de Moraes
Public Library of Science (PLoS)
This study analyzed the physiological adjustments caused by the use of the Elevation training mask® (2.0), an airflow restriction mask (ARM) during continuous exercise. Eighteen physically active participants (12 men and 6 women) were randomized to two protocols: continuous exercise with mask (CE-ARM) and continuous exercise without mask (CE). Exercise consisted of cycling for 20 minutes at 60% of maximum power. Metabolic variables, lactate, and gas concentration were obtained from arterialized blood samples at pre and post exercise. Continuous expired gases and myoelectric activity of the quadriceps were performed at rest and during the test. We observed no reduction in oxygen saturation in CE-ARM, leading to lower pH, higher carbon dioxide, and greater hematocrit (all p <0.05). The expired gas analysis shows that the CE-ARM condition presented higher oxygen uptake and expired carbon dioxide concentrations (p <0.05). The CE-ARM condition also presented lower ventilatory volume, ventilatory frequency, and expired oxygen pressure (p <0.05). No changes in electromyography activity and lactate concentrations were identified. We conclude that using ARM does not induce hypoxia and represents an additional challenge for the control of acid-base balance, and we suggest the use of ARM as being suitable for respiratory muscle training.
Cássia L. Teodoro, Arthur F. Gáspari, Ricardo Berton, João F. Barbieri, Manoel Silva, Luz A.A. Castaño, Patrícia Guimarães, and Antonio C. Moraes
Ovid Technologies (Wolters Kluwer Health)
Abstract Teodoro, CL, Gáspari, AF, Berton, R, Barbieri, JF, Silva, M, Castaño, LAA, Guimarães, P, and Moraes, AC. Familiarization with airflow-restriction mask during resistance exercise: Effect on tolerance and total volume. J Strength Cond Res 33(7): 1762–1765, 2019—This study investigated whether familiarization with the airflow-restriction mask (AIRfr) increases tolerance and avoids negative effects on performance of resistance exercise (RE). Ten resistance-trained male subjects performed a familiarization session (FAM), followed by 2 testing sessions, with the AIRfr and without airflow restriction (SHAM) in a counterbalanced and randomized cross-over design. The FAM was performed with the same number of sets, load, and level of airflow-restriction as the AIRfr experimental session. Each session consisted of 4 sets of the leg press exercise with 70% 1 repetition maximum until voluntary failure and a 90-second rest interval between sets. During the FAM, 4 of the 10 subjects expressed some intolerance to the use of airflow restriction. Total volume was lower in the FAM than in the AIRfr (p = 0.01) and the SHAM (p = 0.02), whereas no differences were observed between the AIRfr and the SHAM (p = 0.90). The first use of the AIRfr may not be well tolerated by all subjects. However, a familiarization session with the AIRfr avoids negative interferences in the total volume during RE.
Arthur F. Gáspari, Leonardo Carvalho, Cássia Lopes Teodoro, Romulo Bertuzzi, Renato Barroso, and Antonio C. Moraes
Ovid Technologies (Wolters Kluwer Health)
Request for Clarification:Developing devices to maximize training-induced adaptations has become a fruitful area. The interesting study of Jagim et al. (4) investigated the acute effects of the Elevation Training Mask 2.0 (ETM) on resistance exercise and sprint performance. Results of the ETM usage
Juliana Melo Altimari, Henrique Bortolotti, Nelson Dos Santos-Junior, Leandro Ricardo Altimari, and Antonio Carlos de Moraes
FapUNIFESP (SciELO)
The aim of this study was to analyze the birth month distribution and anthropometric measurements of U-15 elite soccer players. The sample consisted of 400 athletes (15.4 ± 0.4 years, 171.0 ± 10.6 cm and 63.0 ± 8.8 kg) participants of the 11th edition of the Brazil U-15 Soccer Cup, who had their birth month information and height and body mass measures obtained from data available on the organization’s website. Athletes were separated according to the categorization of chronological age into four-month periods: 1st quarter (1st QDT), athletes born between January and April; 2nd quarter (2nd QDT), those born between May and August, and 3rd quarter (3rd QDT), those born between September and December. The non-parametric chi-square test (X2) was used to analyze the possible differences between observed and expected birth date distributions in the four-month periods. The significance level was P<0.05. The results show that the number of players born in 1st QDT was higher when compared to 2nd QDT and 3rd QDT (P<0.05), and higher when compared to 2nd QDT with 3rd QDT (P<0.05). For variables height and body mass, it was observed that players born in 1st QDT presented values significantly higher than those born in 2nd QDT and 3rd QDT (P<0.05). In the same way, players born in 2nd QDT presented higher values than those born in 3rd QDT (P<0.05).It could be concluded that the relative age effect exerts an influence on the selection of Brazilian U-15 soccer players because it is associated with differences in the anthropometric characteristics of these young players.
Bruno P. C. Smirmaul, Antonio Carlos de Moraes, Luca Angius, and Samuele M. Marcora
Springer Science and Business Media LLC
Cleiton Augusto Libardi, Thiago Mattos Frota Souza, Miguel Soares Conceição, Mara Patricia Traina Chacon-Mikahil, Carlos Ugrinowitsch, Valéria Bonganha, Marcio Franco Fazolin, Antonio Carlos de Moraes, and Cláudia Regina Cavaglieri
IOS Press
BACKGROUND AND OBJECTIVE: Maximal voluntary isometric contraction (MVIC) is used to determine both peak torque (PT) and rate of torque development (RTD). Familiarization sessions are usually performed to stabilize PT and RTD when performing MVIC. However, it is not clear how many familiarization sessions are required to achieve such stability in different age groups. METHODS: Thirty-three healthy individuals were divided into three groups: young group (YG; 5 men and 7 women, age 22.75 ± 4.53 years), middle-aged group (MAG; 6 men and 5 women, age 50.45 ± 6.12 years) and elderly group (EG; 6 men and 4 women, age 67.80 ± 7.28 years). Individuals performed the MVICs using an isokinetic dynamometer, in four different occasions separated by at least 72 hours. RESULTS: There were no differences in PT and RTD between familiarization sessions for all age groups ( P> 0.05). CONCLUSIONS: Our findings suggest that the present protocol of MVIC is capable of stabilizing PT and RTD in the first testing session in young, middle-aged and elderly groups.
Cleiton A. Libardi, Thiago M. F. Souza, Miguel S. Conceição, Valéria Bonganha, Mara Patricia T. Chacon-Mikahil, Cláudia R. Cavaglieri, Antonio C. de Moraes, and Carlos Ugrinowitsch
Wiley
The aim of this study was to investigate the effects of the ageing process in the electromechanical delay (EMD), rate of torque development (RTD) and peak torque (PT) of the knee extensor muscles. The volunteers were assigned to three groups: young group (YG – 23·44 ± 4·74 years, 78·14 ± 15·11 kg, 1·72 ± 0·05 m), middle‐aged group (MAG – 49·56 ± 6·06 years, 72·01 ± 14·07 kg, 1·67 ± 0·06 m) and elderly group (EG – 68·67 ± 9·06 years, 67·96 ± 7·60 kg, 1·64 ± 0·07 m). The PT and RTD were assessed during maximal voluntary ballistic isometric contractions (MVBIC) in the isokinetic dynamometer. Muscle electrical activity was recorded (EMG) during MVBIC in the vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) muscles. The EMD was calculated during the MVBIC, through the time interval between the EMG onset and torque onset. The PT and RTD were higher in the YG than in the MAG (P = 0·02; P = 0·01, respectively) and in the EG (P = 0·002; P = 0·0004, respectively). There were no significant differences in EMD among the three age groups for the VL, VM and RF (P>0·05) muscles. We conclude that age affects the PT and RTD, but not EMD of the VL, VM and RF muscles.
D. C. P. G. Leone, P. Pezarat, M. J. Valamatos, O. Fernandes, S. Freitas, and A. C. Moraes
Wiley
AbstractThis study investigated the acute effect of a low‐volume static and dynamic stretching on maximal isometric peak force (MIPF), time to maximal isometric force (TMIF), rate of force production (RFP) and average amplitude of the surface EMG (AvgEMG) of the main agonist muscles acting on the bench press maximum isometric force exercise. Thirty subjects were randomly divided into three groups: static stretch (SG: 22.8±5.6 years, 176.6±3.5 cm, 74.4±5.9 kg), dynamic stretch (DG: 21.4±3.9 years, 178.4±7.2 cm, 71.7±8.2 kg) and control group (CG: 20.4±3.6 years, 179.8±5.8 cm, 74.4±9.8 kg). SG performed two 30‐s repetitions and DG performed 10 repetitions of each of the two different exercises for the pectoralis major and triceps brachii. The MIPF, TMIF, RFP and AvgEMG of the pectoralis major (sternocostal part) and triceps brachii (long and lateral head) were measured before and immediately after the stretching protocols. A significant decrease in the MIPF from pre‐ to post‐stretching was observed in both SG (p <0.001) and DG (p <0.05). No significant differences were found in the CG for all force parameters. No significant differences in the TMIF and RFP from pre‐ to post‐stretching were found in the three groups. The SG showed a significant (p <0.05) decrease in the AvgEMG of the three muscles, whereas no significant differences were found for the DG and CG. These findings suggest that a low‐volume static and dynamic stretching adversely affects efforts of muscle maximal strength of the upper limb muscles studied, but it does not seem to affect TMIF or RFP.
Marcelo Vitor da Costa, Henrique Bortolotti, Thiago Viana Camata, Jefferson Rosa Cardoso, Rubens Da Silva, Taufik Abrão, Antonio Moraes, and Leandro Altimari
FapUNIFESP (SciELO)
1,5 Abstract - The aim of this study was to compare the electromyographic indices of fatigue (slope of median frequency) calculated with the fast Fourier transform (FFT) and wavelet transform (WT) in trained and untrained individuals during cycle exercise. A second objective was to compare the variance of the spectral parameters (median frequency - MF) obtained by the FFT and WT during exercise. Twelve cyclists and non-cyclists performed a maximal incremental test to determine the peak power (W p ) and electromyographic activity of the vastus lateralis (VL), rectus femoris (RF), biceps femoris (BF), semitendinous (ST) and tibialis anterior (TA). Mean values of median frequency, determined by the FFT and WT, were used for the spectral analysis of the electromyographic signals of the studied muscles. The analyzed parameters were obtained for each time period corresponding to 0, 25, 50, 75, and 100% of total duration of the maximal incremental test. No statistically significant differences were found in the values of MF and electromyographic indices of fatigue between the two techniques (FT and WT) both in the cyclists and non-cyclists group (P>0.05). Regarding the MF variance, statistically significant differences were found in all analyzed muscles, as well as in different time periods, both in the cyclists and non-cyclists groups when comparing the FFT and WT techniques (P<0.05). The WT seems to be more adequate to dynamic tasks, since it does not require the signal to be quasi-stationary, unlike the limitation imposed upon the use of the FFT.
Eduardo Bodnariuc Fontes, Alexandre Hideki Okano, Bruno De Paula Smirmaul, Leandro Ricardo Altimari, Ezequiel Moreira Gonçalves, Ricardo Okada Triana, and Antonio Carlos de Moraes
FapUNIFESP (SciELO)
Ronei Silveira Pinto, Cíntia Ehlers Botton, Bruno Tomasi Kuckartz, Cláudia Silveira Lima, Antonio Carlos Moraes, and Martim Bottaro
FapUNIFESP (SciELO)
Strength training has been reported as an important tool for enhancing and maintaining health. Resistance exercises can be executed unilaterally or bilaterally. Some studies have reported lower strength and electromyography (EMG) signal values in bilateral conditions than the sum of these values in unilateral conditions. This difference in strength and EMG is called the bilateral deficit. The aim of this study was to evaluate the strength and EMG activity of the rectus femoris and vastus lateralis during unilateral and bilateral isometric knee extension. The sample consisted of 10 non-resistance trained males aged 18 to 30 years. Strength and EMG were recorded through use of a load cell and surface electrodes, respectively. A 120o knee extension was used for the isometric knee extension test. The results showed significantly higher values for strength and EMG signal (p <0.05) in unilateral conditions, as well as bilateral deficit in both strength and EMG signal. These results suggest that unilateral training promotes greater muscle stimulation, and can thus represent an important strategy to be used in the prescription of strength training exercises.
R.S. Oliveira, R.E. Pedro, H. Bortolotti, R.A. da Silva, T. Abrão, J.M. Altimari, T.V. Camata, A.C. Moraes, and L.R. Altimari
Centro Andaluz de Medicina del Deporte
Caroline Tosini Felicissimo, José Luiz Dantas, Melissa Luiza Moura, and Antônio Carlos de Moraes
FapUNIFESP (SciELO)
O objetivo deste estudo foi analisar o desempenho e as respostas eletromiográficas dos músculos Reto Femoral, Bíceps Femoral e Gastrocnêmio Medial durante protocolo de saltos verticais. Participaram 13 voleibolistas do sexo feminino (15,6 ± 0,9 anos). Inicialmente foi realizado um protocolo de potência máxima (três saltos máximos), seguido do protocolo de resistência de saltos (ciclos de três saltos máximos em aproximadamente 10 segundos (s) - um salto a cada três s, com recuperação de 15 s). O tempo de duração do protocolo de resistência foi de 20 minutos. Foi usada a técnica do salto com contramovimento sem ajuda dos braços, sobre tapete de contato. Para tratamento dos dados os saltos foram divididos em quatro períodos com 12 ciclos cada um. Os resultados mostraram queda na altura dos saltos de aproximadamente 1,3cm entre os períodos de 1 a 4, sendo que, essa queda foi mais significativa nos 3º e 4º períodos em comparação ao 1º e 2º. Entretanto, com relação às variáveis RMS e FM, não ocorreu alteração nas respostas eletromiográficas entre músculos e períodos. Concluiu-se, assim, que a fadiga pode depender de variáveis psicofisiológicas, ao nível do SNC, que também influem no desempenho.
Cleiton Silva Correa, Bruna Gonçalves Cordeiro da Silva, Cristine Lima Alberton, Eurico Nestor Wilhelm Neto, Antonio Carlos de Moraes, Claudia Silveira Lima, and Ronei Silveira Pinto
FapUNIFESP (SciELO)
The aim of this study was to compare maximal isometric force (MIF) and the electrical activity of the vastus medialis, vastus lateralis, rectus femoris, gluteus maximus and biceps femoris long head muscles between maximal voluntary contractions (MVC) performed at different joint angles, and to identify the most suitable positions to normalize the electromyography (EMG) signals from each of these muscles when they are activated under dynamic conditions. Ten men ranging in age from 20 to 30 years, who were familiar with strength training exercise, were studied. MVC at different joint angles of the knee extensors and flexors (0°, 60°, 90°) and hip extensors (-30°, 0°, 60°) and flexors (90°, 120°) were tested. The MIF values differed significantly between the 60° knee flexion and 60° and 90° knee extension positions (p 0.05). Significantly higher EMG values were only observed for the rectus femoris muscle at 90° knee extension (p 0.05). These results suggest that the 60° knee joint flexion position is the most suitable for assessment of knee extension and flexion MIF, and that all positions tested in this study are suitable for the assessment of hip flexion and extension.
João Julio Garavelo, Leandro Ricardo Altimari, Thiago Viana Camata, José Luiz Lopes Vieira, Taufik Abrão, and Antonio Carlos Moraes
Universidade Estadual de Maringa
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.
Thiago V Camata, Leandro R Altimari, Henrique Bortolotti, Jose L Dantas, Eduardo B Fontes, Bruno PC Smirmaul, Alexandre H Okano, Mara PT Chacon-Mikahil, and Antonio C Moraes
Ovid Technologies (Wolters Kluwer Health)
Camata, TV, Altimari, LR, Bortolotti, H, Dantas, JL, Fontes, EB, Smirmaul, BPC, Okano, AH, Chacon-Mikahil, MPT, and Moraes, AC. Electromyographic activity and rate of muscle fatigue of the quadriceps femoris during cycling exercise in the severe domain. J Strength Cond Res 25(9): 2537-2543, 2011—This study compared the activation pattern and the fatigue rate among the superficial muscles of the quadriceps femoris (QF) during severe cycling exercise. Peak oxygen consumption (&OV0312;o2peak) and maximal accumulated oxygen Deficit (MAOD) were established by 10 well-trained male cyclists (27.5 ± 4.1 years, 71.0 ± 10.3 kg, 173.4 ± 6.6 cm, mean &OV0312;o2peak 56.7 ± 4.4 ml·kg−1·min−1, mean MAOD 5.7 ± 1.1 L). Muscle activity (electromyographic [EMG] signals) was obtained during the supramaximal constant workload test (MAOD) and expressed by root mean square (RMS) and median frequency (MF slope). The RMS of the QF, vastus lateralis (VL) and vastus medialis (VM) muscles were significantly higher than at the beginning after 75% of exercise duration, whereas for the rectus femoris (RF), this was observed after 50% of exercise duration (p ≤ 0.05). The slope of the MF was significantly higher in the RF, followed by the VL and VM (−3.13 ± 0.52 vs. −2.61 ± 0.62 vs. −1.81 ±0.56, respectively; p < 0.05). We conclude that RF may play an important role in limiting performance during severe cycling exercise.