Matheus Bordini Cintra*

cintra@unifesp.br

Priscilla Silva Guedes**

prigue78@yahoo.com.br

Ricardo Luís Fernandes Guerra***

ricardo.guerra@unifesp.br

*Sports Science Laboratory - UNIFESP, Santos/SP

Graduation in Physical Education - UNIFESP

Futsal coach at the University of Vale do Paraíba - UNIVAP

Physical Education teacher at Maple Bear School

**Sports Science Laboratory - UNIFESP, Santos/SP

Universidade São Judas Tadeu, Santos/SP

Graduation in Physiotherapy - Santa Cecília University - UniSanta

Postgraduate in Physiotherapy in Geriatrics and Gerontology - USP

Master's Degree: Health Sciences - UNIFESP

Member of the Study and Research Group in Sports Sciences - GEPCE

***Sports Science Laboratory - UNIFESP, Santos/SP

Department of Human Movement Sciences, UNIFESP, Santos/SP

Graduation in Physical Education - UFSCar

Master's Degree: Physiological Sciences - UFSCar

Doctorate in Physiological Sciences - UFSCar

Leader of the Sports Science Studies and Research Group - GEPCE

Coordinator of the Sports Sciences Laboratory - LaCE

(Brazil)

Reception: 09/22/2023 - Acceptance: 08/05/2023

1st Review: 06/16/2023 - 2nd Review: 08/02/2023

Accessible document. Law N° 26.653. WCAG 2.0

Suggested reference: Cintra, M.B., Guedes, P.S., & Guerra, R.L.F. (2023). Binaural Beats and its Applications in Sports and Physical Exercise. Lecturas: Educación Física y Deportes, 28(306), 222-234. https://doi.org/10.46642/efd.v28i306.3681

 

Abstract

    The auditory illusion caused when two tones of similar frequencies are heard through stereo sound is called Binaural Beats and has been used in several areas, such as relaxation, attention and memory, mood regulation and more recently in the field of physical exercise. Thus, the aim of the study was to analyze the effects of Binaural Beats and its possible applications in sports and physical exercise. An integrative bibliographic review was carried out in the databases: PubMed, Scielo, Embase and SportDiscus. The descriptors used were Binaural Beats, OR Binaural Beating, OR Binaural Beat Therapy, OR Binaural auditory, OR Binaural frequency combined with Exercise, OR Physical activity, OR Sport. The search totaled 56 scientific studies (articles or abstracts) and four met the eligibility criteria being included and analyzed, showing that the use of Binaural Beats seems to contribute both to the improvement of performance and to recovery from exercise. However, it depends on the exposure time, frequency used and time of intervention.

    Keywords: Binaural frequency. Exercise. Physical activity. Sport. Performance.

 

Resumo

    A ilusão auditiva causada quando dois tons de frequências semelhantes são ouvidos por meio de som estéreo é denominada de Binaural Beats e tem sido utilizado em diversas áreas, tais como relaxamento, atenção e memória, regulação de humor e mais recentemente no âmbito do exercício físico. Assim, o objetivo do estudo foi analisar os efeitos do Binaural Beats e suas possíveis aplicações no âmbito esportivo e do exercício físico. Foi realizada uma revisão bibliográfica integrativa nas bases de dados: PubMed, Scielo, Embase e SportDiscus. Os descritores utilizados foram Binaural Beats, OR Binaural Beating, OR Binaural Beat Therapy, OR Binaural auditory, OR Binaural frequency combinados com Exercise, OR Physical activity, OR Sport. A busca totalizou 56 estudos científicos (artigos ou resumos) e quatro atenderam aos critérios de elegibilidade sendo incluídos e analisados, mostrando que o uso do Binaural Beats parece contribuir tanto para a melhora do desempenho, quanto para a recuperação do exercício. Porém, depende do tempo de exposição, frequência utilizada e momento da intervenção.

    Unitermos: Frequência binaural. Exercício. Atividade física. Esporte. Desempenho.

 

Resumen

    La ilusión auditiva que se produce cuando se escuchan dos tonos de frecuencias similares a través de un sonido estéreo se denomina Binaurales y se ha utilizado en diversas áreas, como la relajación, la atención y la memoria, la regulación del estado de ánimo y, más recientemente, en el campo del ejercicio físico. Así, el objetivo del estudio fue analizar los efectos de Binaurales y sus posibles aplicaciones en el deporte y el ejercicio físico. Se realizó una revisión bibliográfica integradora en las bases de datos: PubMed, Scielo, Embase y SportDiscus. Los descriptores utilizados fueron Binaural Beats, OR Binaural Beats, OR Binaural Beat Therapy, OR Binaural auditivo, OR Binaural frecuencia combinada con ejercicio, OR Actividad física, OR Deporte. La búsqueda totalizó 56 estudios científicos (artículos o resúmenes) y cuatro cumplieron con los criterios de elegibilidad incluidos y analizados, lo que demuestra que el uso de Binaurales parece contribuir tanto a la mejora del rendimiento como a la recuperación del ejercicio. Sin embargo, depende del tiempo de exposición, la frecuencia utilizada y el tiempo de intervención.

    Palabras clave: Frecuencia binaural. Ejercicio físico. Actividad física. Deporte. Rendimiento.

 

Lecturas: Educación Física y Deportes, Vol. 28, Núm. 306, Nov. (2023)

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Introduction 

 

    Binaural Beats are an auditory illusion caused when two tones of similar frequencies are heard through stereo sound such as headphones. Binaural Beats listeners “hear” a beat of a frequency equal to the difference between the two frequencies applied to the right and left ear. Thus, the individual who hears a frequency of 130 Hz in the left ear and the frequency of 120 Hz in the right, in fact, the individual hears a frequency of 10Hz. This happens because there is a brainstem response that originates in the superior olivary nucleus because of auditory stimuli of different frequencies perceived in each ear. (McConnell, Froeliger, Garland, Ives, & Sforzo, 2014; Lee, Song, Shin, & Lee, 2019; Basu, & Banerjee 2022)

 

    Several studies have reported positive effects of Binaural Beats on clinical outcomes, including heart rate, blood pressure (Kennerly, 2004; Bakaeva et al., 2021), alertness, depression and mood states (Lane, Kasian, Owens, & Marsh, 1998; Wahbeh, Calabrese, & Zwickey, 2007; Cantor, & Stevens, 2009), relaxation (Lee-Harris, Timmers, Humberstone, & Blackburn, 2018), attention and memory. (Basu, & Banerjee, 2022) and anxiety and stress reduction (Conte Chan, & Chavarría Calvo, 2017; Lee, Lee, Ahn, Hon, & Yoon, 2022)

 

    The meta-analysis study by Garcia-Argibay, Santed, & Reales (2019) corroborated the efficacy and effects of Binaural Beats on cognition, anxiety and analgesia. According to the authors, exposure to Binaural Beats is capable of affecting cognition, reducing anxiety levels and pain perception. However, the effect and magnitude of the effect depend on the time of exposure, when it occurs, as well as the type of frequency used. The same authors stated that, to ensure maximum effectiveness, long periods of exposure to Binaural Beats are advisable, the ideal minimum time being between 9 and 10 minutes. (Garcia-Argibay et al., 2019)

 

Source: Bing Image Creator (#Efdeportes)

 

    The frequencies, because they have specific amplitudes, were named by the letters of the Greek alphabet, respecting their spectrum: Delta (0.5-4 Hz), Theta (4-7 Hz), Alpha (7-13 Hz), Beta (13-30 Hz) e Gama (30-50 Hz). (Jirakittayakorn, & Wongsawat, 2018)

 

    Regarding the moment, the exposure of Binaural Beats was effective in two moments, before the task and before/during the task comparing to the effect produced only during the task. For tasks related to memory, the type of frequency had both a positive and a negative effect, with alpha, beta and gamma frequencies being effective, while theta frequency was not. (Garcia-Argibay et al., 2019)

 

    Regarding physical exercise/sport as an intervention interface of Binaural Beats, few studies are found. Some researchers have studied the sleep quality and post-sleep mental state of young soccer players in order to improve their performance (Abeln, Kleinert, Strüder, & Schneider, 2014). Others used the Binaural Beats intervention as a post-exercise recovery strategy (McConnell et al., 2014; Yefremenko et al., 2016), or to assess reaction time and electroencephalography (EEG) in adolescent swimmers (Mekky, Said, Elsherif, Zeineldin, & Badreldin, 2017). However, the literature in this context is still scarce.

 

    If proven, the description of the effects of Binaural Beats and its possible applications in the area of ​​physical exercise/sports, can contribute to the improvement of the performance of athletes and exercise practitioners, or even be a strategy for recovery of the same, being able such practitioners have enhanced performance.

 

    Given this context, some questions are relevant: what effects are generated in the use of Binaural Beats and how can they be applied in the context of physical and sports exercise? Would it be possible to say that the use of Binaural Beats can contribute to the practice of physical exercise? Thus, the present study aims to analyze the effects of Binaural Beats and its possible applications in sports and physical exercise.

 

Methods 

 

    The study is an integrative literature review on the effects of Binaural Beats and its possible applications in sports and physical exercise and followed the procedures according Dantas, Costa, Costa, Lúcio, & Comassetto (2022). It was not used data from humans or experimental animals, directly or indirectly, and was developed respecting the current legal norms regarding intellectual protection, good scientific practices and ethics in research. Its ethical and scientific content was signed by the study author´s and by the department heads of the institution, as instructed by the CEP - UNIFESP Research Ethics Committee for research that did not directly involve human beings.

 

Search strategy 

 

    The search was carried out with no lower date limit until February 5, 2022. An advanced search was performed in the PubMed, Scielo, Embase and SportDiscus databases. The descriptors used were Binaural Beats OR Binaural Beating OR Binaural Beat Therapy OR Binaural auditory OR Binaural frequency combined with Exercise OR Physical activity OR Sport. The descriptors were searched in both English and Portuguese.

 

Eligibility criteria 

 

    Studies that performed intervention using Binaural Beats (associated or not with other actions) published in complete versions or not, and with or without a control group, but correlated to athletes, sports, exercise or physical activity, were considered for inclusion. Duplicate articles and literature reviews were excluded for the purpose of presenting results. Searches were not limited by time.

 

Study selection and data extraction 

 

    The articles were initially read by title and abstract. After the inclusion of the article, a complete reading was performed and a table was made with the identification of the articles with author, year, volunteers, analyzed variables, frequency used, intervention time and the main results.

 

Results 

 

    The search totaled 56 scientific studies adding up all the databases searched. Eight duplicate articles were excluded, leaving 48 studies. By reading the titles and/or abstracts, another 44 were excluded because had not the intervention using Binaural Beats correlated to athletes, sports, exercise or physical activity. Therefore, the research resulted in 4 studies that were used in this work (Figure 1).

 

Source: Authors

 

    The identification and main information regarding the included studies can be seen in Table 1.

 

Author/ Year	Volunteers	Variables analyzed	Frequency used	Time	Main Results
Abeln et al. (2014)	18 male sub-elite soccer players (15 to 17 years old)	Sleep quality and post-sleep mental state	Alpha (8 Hz), Theta (6 Hz), Delta (2 Hz) and Theta (4 Hz)	4 periods of 22.5 minutes per night for 8 weeks	Improved sleep quality and post-sleep status.
McConnel et al. (2014)	21 university students (18 to 29 years old) (14 male/7 female)	Autonomic dynamics and heart rate variability	Theta (4-7 Hz)	1 experimental session of 20 minutes	Increased parasympathetic activation, increased sympathetic withdrawal, and increased self-reported post-exercise relaxation.
Yefremenko et al. (2016)	15 trained runners (19 to 21 years old) (sex*)	Correlation of physiological determinants and performance of sprinters, taking into account the effects of vibration, negative air ionization and Binaural Beats	Theta (4-7 Hz)	20 minutes per session for 4 weeks (frequency*)	Positive effect on recovery strategies related to the runners' psychophysiological condition, suggesting an improvement in the sprinters' muscular capacity, generating greater mechanical energy.
Mekky et al. (2017)	11 teenagers swimmer of elite (4 female/ 7 male) (age*)	Electroencephalographic (EEG) and reaction time	Alpha	18 sessions (time*)	EEG frequencies were significantly decreased (both qualitatively and quantitatively) in swimmers. In addition, there was a significant improvement in reaction time.

* = Missing information in the study. Source: Authors

 

Discussion 

 

    In view of the searches carried out in the databases, it was possible to perceive that it is not common for the use of Binaural Beats to be linked to physical exercise or sport in research, whether for performing tasks during the activity or even in order to improve post-operative recovery. action. However, there is a trend of new studies since the 4 studies included here were published between 2014 and 2017, in addition to others that, despite not meeting the criteria, were carried out in the last decade.

 

    Investigating the effects of Binaural Beats on athletes, Mekky et al. (2017) studied reaction time and electroencephalography in 11 adolescent (7 male and 4 female) elite swimmers, who underwent 18 sessions of mental training, including relaxation techniques. Subjects were randomly divided into 2 groups, 7 in the first and 4 in the second. In group 1, the individuals underwent alpha-frequency Binaural Beats and music therapy. In group 2, only music therapy. Assessments were performed before and after the session, with a significant change in the electroencephalographic waves and reaction time (p=0.05), both quantitatively and qualitatively. The authors concluded that relaxation techniques, Binaural Beats associated with music can have a positive effect on the performance of swimmers.

 

    McConnell et al. (2014) aimed to assess heart rate variability under the intervention of Binaural Beats. Twenty-one (21) college students (18 to 29 years old) underwent an individualized aerobic exercise protocol (running, according to the American College of Sports Medicine regulations). A warm-up and cool-down was performed at 50% VO2 max for 5 minutes. The intervention was performed on a treadmill at 70% of VO2 max for 20 minutes. After the session, the subjects participated in a double-blind intervention, in which 10 subjects listened to the Binaural Beats while 11 to the placebo (noise) for 20 minutes and during this period the heart rate was monitored. Results demonstrated that acute exposure to Binaural Beats resulted in significantly greater parasympathetic activation, increased sympathetic withdrawal, and increased post-exercise self-reported relaxation compared to the placebo group.

 

    Yefremenko et al. (2016) also studied the use of Binaural Beats as one of the post exercise (recovery) strategies. The study was carried out with 15 trained runners (19 to 21 years old), evaluated by running-specific motor tests. In the intervention protocol, Binaural Beats was used in the frequency between 4-7 Hz (Theta) for 20 minutes after the running time, power and speed motor tests were applied. Runners were advised to close their eyes and relax. However, in addition to the intervention with Binaural Beats, two other recovery strategies were used: vibration effects and negative air ionization. The findings showed a positive effect on important variables for post-exercise recovery on the runners' psychophysiological condition. Although this study uses other tools along with Binaural Beats, it is possible to say that its use can be applied concomitantly with other strategies, and may even enhance its effects. (Yefremenko et al., 2016)

 

    In addition, Abeln et al. (2014) carried out a study analyzing 18 sub-elite soccer players (aged between 15 and 17 years) under Binaural Beats intervention for eight weeks to verify whether their sleep quality improved or not. Control and experimental groups slept on the same pillow, but only the experimental group had built-in speakers in their pillows. The stimulus was given for four periods, each of 22.5 minutes, starting with the alpha frequency (8 Hz) and later changing to theta frequencies (6 Hz), delta (2 Hz) and returning to theta frequency.

 

    For the evaluations, three questionnaires were applied: sleep diary, Self-Assessment questionnaire of Sleep and Awakening quality (SSA), and a psychophysical state of the participants (Mood) that should be answered on a fixed day of the week, approximately 30-60 minutes right after waking up. The experimental group had a significant result in the “sleep diary” questionnaire, in time to go to bed (p=0.03) and total sleep time (p<0.01). The same group had significant results, in relation to the control group, in the SSA questionnaire, and "Mood" in the variables sleep quality (p<0.05), quality of awakening (p<0.01), physical fitness (p<0.01), recovery (p=0.03), motivational state (p<0.001) and sleepiness (p<0.001).

 

    Thus, Binaural Beats intervention appears to be a valuable method to support and improve sleep quality and post-sleep state of athletes in a non-invasive way (Abeln et al., 2014). In this context, the findings of Lee et al. (2019) corroborate the beneficial effects of Binaural Beats on sleep observed in 50 healthy individuals (49 men and 1 woman), aged between 23 and 27 years. In the intervention, several periods were used, alternating silence with the stimulus of 6 Hz (Theta), which in turn is the frequency activated in brain activity during stage 1 of sleep (non-rapid eye movement). The authors suggest that this protocol may provide an effective way to improve sleep quality and sleep induction at stage 1, at theta frequency (6 Hz).

 

    Thus, the use of Binaural Beats becomes important not only regarding the tasks performed during exercise, or after exercise, but mainly in the psychobiological variables that indirectly influence physical exercise, such as sleep. The psychobiological variables are supporting the performance of the exercise, because they are variables that influence the tasks necessary for the accomplishment of the same.

 

    Lane et al. (1998) studied the use of Binaural Beats in tasks such as alertness and mood swings. The authors performed an intervention in 29 healthy individuals (between 19 and 51 years of age, 10 men and 19 women) with the beta (16 Hz and 24 Hz) and theta/delta (1.5 Hz and 4 Hz) frequency during the test. surveillance that lasted approximately 30 minutes. The study concluded that Binaural Beats of beta frequency significantly improved, (p<0.05), the mood state in these subjects in relation to theta/delta frequencies. Also, Basu, & Banerjee (2022) recently conducted a meta-analysis and systematic review to examine the effect of Binaural Beat intervention on memory and attention. Fifteen studies met the inclusion criteria allowing the authors conclude that there is a positive effect of Binaural Beat intervention on cognitive functions, in this case, memory and attention in humans. Another possibility tested with the intervention by Binaural Beats was related to depression, which can affect even athletes at different times of their careers. (Wolanin, Gross, & Hong, 2015)

 

    Cantor, & Stevens (2009) studied the use of beta frequency Binaural Beats (14 Hz) to alleviate the symptoms of the disease in 16 people (11 women and 5 men, aged between 20 and 67 years), referred by a physician. psychiatric to participate in the study. For the intervention, the individuals were divided into two random groups: group 1 listened to Binaural Beats every day for 30 minutes for 8 weeks, while group 2 listened to a simulation of Binaural Beats in the first 4 weeks and in the last 4, effectively, the Binaural Beats. The results revealed a significant reduction in depression (p<0.01) in the group that listened to Binaural Beats every day. The findings indicate that the protocol used can enable a non-drug therapy against the disease. However, caution is still needed to assert the significant effects of Binaural Beats on several variables.

 

    Parreira et al. (2020) performed an intervention by Binaural Beats in 13 telemarketing workers to investigate its effects on anxiety, stress, sleep quality, general health and productivity at work. The sessions consisted of 20 minutes at a frequency between 0.5 Hz and 18 Hz, three times a week, for 6 weeks. Questionnaires were applied at the beginning of the intervention and after the sixth week. Although the study was not conducted with flippers or physical activity practitioners, and the results did not reach statistical significance (but percentage), the intervention positively affected the scores related to all the variables studied. In addition, it can be observed that there are differences between the intervention protocols used through Binaural Beats, whether in sports and physical exercise, or not.

 

    Garcia-Argibay et al. (2019), in a literature review and meta-analysis study, stated that the effect and magnitude of this effect by Binaural Beats depend on the exposure time (ideal around 9 to 10 minutes) and the when it occurs (preferably before and before/during). In this context, some studies (McConnell et al., 2014; Yefremenko et al., 2016; Abeln et al., 2014) used a longer time in their protocols than that reported in the review study, probably to ensure efficacy. Mekky et al. (2017) performed an intervention during the task, collecting the reaction time results before and after the intervention, also corroborating the finding of the literature review and meta-analysis by Garcia-Argibay et al. (2019). Thus, more studies are needed, bringing Binaural Beats as an intervention interface in different conditions of sports practices and physical exercise, whether for performance improvement, as a post-activity recovery strategy, or to improve psychobiological variables supporting the performance of these practices (Cintra, 2020). As a limitation, despite the care taken with the method, this study could have evaluated the level of evidence of the eligible articles.

 

Conclusion 

 

    The use of Binaural Beats seems to be effective in sports and physical exercise, in such a way that its effects are positive for relaxation, reaction time, sleep quality, post-sleep mental state and heart rate variability, which can enable both performance improvement and exercise recovery. However, the differences on the exposure time, frequency used and time of intervention signalize that more studies addressing this issue still are needed.

 

References 

 

Abeln, V., Kleinert, J., Strüder, H.K., & Schneider, S. (2014). Brainwave entrainment for better sleep and post-sleep state of young elite soccer players - a pilot study. European Journal of Sport and Science, 14(5), 393-402. https://doi.org/10.1080/17461391.2013.819384

 

Bakaeva, ZV, Shumov, DE, Yakunina, EB, Starshinov, YP, Sveshnikov, DS, Torshin, VI, Dorokhov, VB, & Karpov, VI (2021). Влияние музыки с эффектом бинауральных биений на параметры сердечного ритма человека в процессе дневного сна [The effect of music embedded with binaural beats on heart rate parameters during nap]. Zh Nevrol Psikhiatr Im S.S. Korsakova, 121(4-2), 31-35. https://doi.org/10.17116/jnevro202112104231

 

Basu, S., & Banerjee, B. (2022). Potential of binaural beats intervention for improving memory and attention: insights from meta-analysis and systematic review. Psychological Research, 16. https://doi.org/10.1007/s00426-022-01706-7

 

Cantor, D.S., & Stevens, E. (2009). QEEG correlates of auditory-visual entrainment treatment efficacy of refractory depression. Journal of Neurotherapy, 13(2), 100-108. https://doi.org/10.1080/10874200902887130

 

Cintra, M. (2020). Efeitos do uso do binaural beats e suas aplicações no âmbito esportivo e do exercício físico: uma revisão narrativa [Trabalho de Conclusão de Curso. Universidade Federal de São Paulo - UNIFESP]. https://repositorio.unifesp.br/xmlui/handle/11600/63542

 

Conte Chan, A., & Chavarría Calvo, M.A. (2017). Dental management of patients with cerebral palsy through the binaural beats. Odontología Vital, (27), 51-58. https://www.researchgate.net/publication/321430263

 

Dantas, H.L. de L., Costa, C.R.B., Costa, L. de M.C., Lúcio, I.M.L., & Comassetto, I. (2022). Como elaborar uma revisão integrativa: sistematização do método científico. Revista Recien - Revista Científica de Enfermagem, 12(37), 334-345. https://doi.org/10.24276/rrecien2022.12.37.334-345

 

Garcia-Argibay, M., Santed, M.A., & Reales, J.M. (2019). Efficacy of binaural auditory beats in cognition, anxiety, and pain perception: a meta-analysis. Psychological Research, 83(2), 357-372. https://doi.org/10.1007/s00426-018-1066-8

 

Jirakittayakorn, N., & Wongsawat, Y. (2018). A Novel Insight of Effects of a 3-Hz Binaural Beat on Sleep Stages During Sleep. Frontiers in Human Neuroscience, 12. https://doi.org/10.3389/fnhum.2018.00387

 

Kennerly, R.C. (2004). QEEG analysis of binaural-beat audio entrainment: a pilot study. Journal of Neurotherapy, 8(22), 122-122.

 

Lane, J., Kasian, S.J., Owens, J.E., & Marsh, G.R. (1998). Binaural auditory beats affect vigilance performance and mood. Physiology and Behavior, 63(2), 249-252. https://doi.org/10.1016/s0031-9384(97)00436-8

 

Lee-Harris, G., Timmers, R., Humberstone, N., & Blackburn, D. (2018). Music for Relaxation: A Comparison Across Two Age Groups. Journal of Music Therapy, 55(4), 439-462. https://doi.org/10.1093/jmt/thy016

 

Lee, M., Song, C.B., Shin, G.H., & Lee, S.W. (2019). Possible Effect of Binaural Beat Combined With Autonomous Sensory Meridian Response for Inducing Sleep. Frontiers in Human Neuroscience, 13(425), 1-16. https://doi.org/10.3389/fnhum.2019.00425

 

Lee, M., Lee, H.J., Ahn, J., Hong, J.K., & Yoon, I.Y. (2022). Comparison of autonomous sensory meridian response and binaural auditory beats effects on stress reduction: a pilot study. Scientific Reports, 12, 19521. https://doi.org/10.1038/s41598-022-24120-w

 

McConnell, P.A., Froeliger, B., Garland, E.L., Ives, J.C., & Sforzo, G.A. (2014). Auditory driving of the autonomic nervous system: Listening to theta-frequency binaural beats post-exercise increases parasympathetic activation and sympathetic withdrawal. Frontiers in Psychology, 5(1248), 1-10. https://doi.org/10.3389/fpsyg.2014.01248

 

Mekky, J., Said, S., Elsherif, S., Zeineldin, M., & Badreldin, T. (2017). Brain wave entrainment using alpha frequency binaural beats on adolescent swimmers. European Journal of Neurology, 24(8), 269. https://onlinelibrary.wiley.com/doi/epdf/10.1111/ene.13367

 

Parreira, R.B., Castro, N.F., Mendes, M.L.R., Salgado, A.I.S., Porter, P., & Cidral-Filho, F. (2020). Effect of Audio-Visual Brain Entrainment on Anxiety, General Health, Stress, Quality of Sleep and Work Productivity and Activity Impairment: A Pilot Study with Telemarketers. International Society for Neurofeedback and Research: NeuroRegulation, 7(4), 173-183.

 

Wahbeh, H., Calabrese, C., & Zwickey, H. (2007). Binaural beat technology in humans: a pilot study to assess psychologic and physiologic effects. Journal of Alternative and Complementary Medicine, 13(1), 25-32. https://doi.org/10.1089/acm.2006.6196

 

Wolanin, A., Gross, M., & Hong, E. (2015). Depression in Athletes: Prevalence and Risk Factors. Current Sports Medicine Reports, 14(1), 56-60. https://doi.org/10.1249/JSR.0000000000000123

 

Yefremenko, A., Shesterova, L., Krajnik, Y., Nasonkina, H., Shuttev, V., Shuteeva, T., Druz, V., & Pyatisotskaya, S. (2016). Correlation between physiological parameters and indicators of special physical readiness of trained sprinters under the influence of recovery means. Journal of Physical Education and Sport, 140, 897-900. https://doi.org/10.7752/jpes.2016.03140

Lecturas: Educación Física y Deportes, Vol. 28, Núm. 306, Nov. (2023)