Injury Causes and Recovery Management Strategies among Singapore CrossFitters
Keywords:
CrossFit, sport injuries, injury management, injury recovery, Singapore
Abstract
CrossFit is a combination of movements from various sport disciplines such as Olympic Weightlifting, Powerlifting and Gymnastics executed at high intensity. It has shown to bring about physiological and psycho-social benefits to members, increasing exercise adherence. Established in 2005, CrossFit has seen an exponential growth since, with 13,991 CrossFit affiliates worldwide. The popularity of the program despite its disposition to injury requires greater attention to its safety. This research aims to understand (1) reasons of injury among CrossFitters; (2) Injury management techniques among CrossFitters. In-depth interviews were conducted with nine CrossFitters from five Singapore CrossFit affiliates. Data was transcribed and thematically analyzed. Findings revealed that causes of injury include poor workout program designs, insufficient physiological knowledge passed down from coaches to athletes, athlete’s impatience when learning new skills as well as athletes conforming to performance and peer pressures. Further, Crossfitters manage their injuries through self-care physiological means and with professional guidance. The study concludes that coaches play a vital role in both the prevention and management of injuries. Therefore, they should design their programs with the athlete’s safety in mind and foster an environment that values patience, strength building discipline and safety. Athletes should also pay extra attention to their movement technique and be self-reflective in their physical capabilities. All athletes should regularly practice conservative physiological recovery methods and seek treatment or diagnosis from medical practitioners when necessary.
References
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Aune, K.T. & Powers, J.M. 2017. Injuries in an Extreme Conditioning Program. Sports Health, 9 (1): 52-58. https://doi.org/10.1177/1941738116674895
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Bandy, W.D., Irion, J. M. & Briggler, M. 1998. The Effect of Static Stretch and Dynamic Range of Motion Training on the Flexibility of the Hamstring Muscles. Journal of Orthopaedic & Sports Physical Therapy, 27 (4): 295-300. https://doi.org/10.2519/jospt.1998.27.4.295
Bergeron, M.F., Nindl, B.C., Deuster, P.A., Baumgartner, N., Kane, S.F., Kraemer, W.J. & O'Connor, F.G. 2011. Consortium for Health and Military Performance and American College of Sports Medicine Consensus Paper on Extreme Conditioning Programs in Military Personnel. Current Sports Medicine Reports, 10 (6): 383-389. https://doi.org/10.1249/jsr.0b013e318237bf8a
Braun, V. & Clarke, V. 2006. Using Thematic Analysis in Psychology. Qualitative Research in Psychology, 3 (2): 77-101. https://www.tandfonline.com/doi/abs/10.1191/1478088706qp063oa
Cheatham, S.W., Kolber, M.J., Cain, M. & Lee, M. 2015. The Effects of Self-Myofascial Release Using a Foam Roll or Roller Massager on Joint Range of Motion, Muscle Recovery, and Performance: a Systematic Review. International Journal of Sports Physical Therapy, 10 (6): 827. https://pubmed.ncbi.nlm.nih.gov/26618062/
Claudino, J.G., Gabbett, T.J., Bourgeois, F., de Sá Souza, H., Miranda, R.C., Mezêncio, B. & Amadio, A.C. 2018. Crossfit Overview: Systematic Review and Metaanalysis. Sports Medicine-Open, 4 (11): 1-14. https://doi.org/10.1186/s40798-018-0124-5
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Crockett, M.C. & Butryn, T. 2018. Chasing Rx: A spatial Ethnography of the CrossFit Gym. Sociology of Sport Journal, 35 (2): 98-107. https://doi.org/10.1123/ssj.2017-0115
CrossFit Level 1 Training Guide. 2019. CrossFit Inc.
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Dawson, M.C. 2017. CrossFit: Fitness Cult or Reinventive Institution?. International Review for the Sociology of Sport, 52 (3): 361-379. https://doi.org/10.1177%2F1012690215591793
Feito, Y., Burrows, E.K. & Tabb, L.P. 2018. A 4-Year Analysis of the Incidence of Injuries among CrossFit-Trained Participants. Orthopaedic Journal of Sports Medicine, 6(10). https://dx.doi.org/10.1177%2F2325967118803100
Fisher, J., Sales, A., Carlson, L. & Steele, J. 2016. A Comparison of the Motivational Factors between CrossFit Participants and Other Resistance Exercise Modalities: a Pilot Study. Journal of Sports Medicine and Physical Fitness, 57 (9): 1227-1234. https://doi.org/10.23736/s0022-4707.16.06434-3
Fletcher, J. 31 May 2018. Dry Needling vs. Acupuncture: Benefits and Uses. Retrieved from https://www.medicalnewstoday.com/articles/321989.php.
Fullagar, H.H., Skorski, S., Duffield, R., Hammes, D., Coutts, A.J. & Meyer, T. 2015. Sleep and Athletic Performance: the Effects of Sleep Loss on Exercise Performance, and Physiological and Cognitive Responses to Exercise. Sports Medicine, 45 (2): 161-186. https://doi.org/10.1007/s40279-014-0260-0
Hackney, R.G. 1994. Nature, Prevention, and Management of Injury in Sport (ABC of Sports Medicine. British Medical Journal, 308 (6940): 1356-1360. https://doi.org/10.1136/bmj.308.6940.1356
Hak, P.T., Hodzovic, E. & Hickey, B. 2013. The Nature and Prevalence of Injury during CrossFit Training. Journal of Strength and Conditioning Research, 22. https://doi.org/10.1519/jsc.0000000000000318
Heinrich, K.M., Patel, P.M., O’Neal, J.L. & Heinrich, B.S. 2014. High-Intensity Compared to Moderate-Intensity Training for Exercise Initiation, Enjoyment, Adherence, and Intentions: an Intervention Study. BMC Public Health, 14 (1): 789. https://doi.org/10.1186/1471-2458-14-789
Huzar, T. 28 March 2019. Does Cupping Therapy Work and What are the Benefits? Retrieved from https://www.medicalnewstoday.com/articles/324817.php.
Järvinen, M.J. & Lehto, M.U. 1993. The effects of Early Mobilisation and Immobilisation on the Healing Process Following Muscle Injuries. Sports Medicine, 15 (2): 78-89. https://doi.org/10.2165/00007256-199315020-00002
Järvinen, T.A., Järvinen, T.L., Kääriäinen, M., Äärimaa, V., Vaittinen, S., Kalimo, H. & Järvinen, M. 2007. Muscle Injuries: Optimising Recovery. Best Practice & Research Clinical Rheumatology, 21 (2): 317-331. https://doi.org/10.1016/j.berh.2006.12.004
Keogh, J.W. & Winwood, P.W. 2017. The Epidemiology of Injuries Across the Weight-Training Sports. Sports Medicine, 47 (3): 479-501. https://doi.org/10.1007/s40279-016-0575-0
Klimek, C., Ashbeck, C., Brook, A.J. & Durall, C. 2018. Are Injuries More Common with CrossFit Training than Other Forms of Exercise?. Journal of Sport Rehabilitation, 27 (3): 295-299. https://doi.org/10.1123/jsr.2016-0040
Kraemer, W.J., Adams, K., Cafarelli, E., Dudley, G.A., Dooly, C., Feigenbaum, M.S. & Newton, R.U. 2002. American College of Sports Medicine. American College of Sports Medicine Position Stand. Progression Models in Resistance Training for Healthy Adults. Medicine & Science in Sports & Exercise, 34 (2): 364-80. https://doi.org/10.1249/mss.0b013e3181915670
Kuhn, S. 2013. The Culture of CrossFit: A Lifestyle Prescription for Optimal Health and Fitness. Senior Theses. United States: Illionis State University.
Langdridge, D. 2004. Introduction to Research Methods and Data Analysis in Psychology. Harlow: Pearson Education.
Lei, F., Min, F., Shichao, J. & Hua, C. 2015. Optimization of Parameters of Yi Zhi Chan Tuina Manipulation Promotes Peripheral Circulation. Journal of Traditional Chinese Medicine, 35 (5): 558-563. http://dx.doi.org/10.1016/S0254-6272(15)30139-4
Gagnon, P. & Long, Z. 2019. Skills Progression Chart, The Barbell Physio. Retrieved from http://bit.ly/tbpchart
Ganfield, L. 2009. Myofascial Release Therapy- SPINE-Health. Available from https://www.spine-health.com/treatment/physical-therapy/myofascial-release-therapy
Maslow, A.H. 1943. A Theory of Human Motivation. Psychological Review, 50 (4): 370-396. https://psycnet.apa.org/doi/10.1037/h0054346
Mehrab, M., de Vos, R.J., Kraan, G.A. & Mathijssen, N.M. 2017. Injury Incidence and Patterns among Dutch CrossFit Athletes. Orthopaedic Journal of Sports Medicine, 5 (12), 2325967117745263. https://doi.org/10.1177/2325967117745263
Meyer, J., Morrison, J. & Zuniga, J. 2017. The Benefits and Risks of CrossFit: a Systematic Review. Workplace Health & Safety, 65 (12): 612-618. https://doi.org/10.1177/2165079916685568
Montalvo, A.M., Shaefer, H., Rodriguez, B., Li, T., Epnere, K. & Myer, G.D. 2017. Retrospective Injury Epidemiology and Risk Factors for Injury in CrossFit. Journal of Sports Science & Medicine, 16 (1): 53-59. https://pubmed.ncbi.nlm.nih.gov/28344451/
Mullins, N. 2015. CrossFit: Remember what You Have Learned: Apply What You Know. Journal of Exercise Physiology Online, 18 (6): 32-44. https://www.researchgate.net/publication/290123696_CrossFit_Remember_what_you_have_learned_apply_what_you_know
Paine, J., Uptgraft, J. & Wylie, R. 2010. CrossFit Study. Fort Leavenworth: Command and General Staff College. http://library.crossfit.com/free/pdf/CFJ_USArmy_Study.pdf
Parkkari, J., Kannus, P., Natri, A., Lapinleimu, I., Palvanen, M., Heiskanen, M. & Järvinen, M. 2004. Active Living and Injury Risk. International Journal of Sports Medicine, 25 (3): 209-216. https://doi.org/10.1055/s-2004-819935
Physiopedia. n.d. Rehabilitation in Sport. Retrieved from https://www.physiopedia.com/Rehabilitation_in_Sport
Poland, B.D. 2002. Transcription Quality. In J.F. Gubrium and J.A. Holstein (eds), Handbook of Interview Research: Context & Method. CA: Sage.
Reynolds, G. 2008. Stretching: the Truth. The New York Times. https://www.nytimes.com/2008/11/02/sports/playmagazine/112pewarm.html
Robertson, E. 2017. CrossFit's Dirty Little Secret. Retrieved from https://www.huffpost.com/entry/crossfitrhabdomyolysis_b_3977598?utm_hp_ref=mostpopular.
Ross, B. 2018. The Controversy behind CrossFit. Retrieved from https://www.livestrong.com/article/545200-the-fall-of-fitness/.
Safran, M.R., Garrett, W.E., Seaber, A.V., Glisson, R.R. & Ribbeck, B.M. 1988. The role of Warmup in Muscular Injury Prevention. The American Journal of Sports Medicine, 16 (2): 123-129. https://doi.org/10.1177/036354658801600206
Schneider, N.C., Coates, W. C. & Yarris, L.M. 2017. Taking Your Qualitative Research to the Next Level: a Guide for the Medical Educator. AEM Education and Training, 1 (4): 368-378. https://dx.doi.org/10.1002%2Faet2.10065
Schroeder, A.N. & Best, T.M. 2015. Is Self Myofascial Release an Effective Preexercise and Recovery Strategy? A Literature Review. Current Sports Medicine Reports, 14 (3): 200-208. https://doi.org/10.1249/jsr.0000000000000148
Simmons, E. 2014. Why I don't do CrossFit. Retrieved from https://www.huffpost.com/entry/why-i-dont-docrossfit_b_5411771?guccounter=1&guce_referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce_referrer_sig=AQAAABhYnVHT_0s4Gnd_vsPEYxydlnXW3-HLjtxK-kTKaNWDr21NlIfgfEEVVfkFZlbFuBgHHzN10_Fyh8wigV_3MVKwRlBfqesBGmJWQVGt5nYSXMbKbWFSSUYlycH0LLeOBZ4qxrRsR46dKKfKsl8Ww80QJ7Rz6zhOOgBmIXbQil.
Smith, M.M., Sommer, A.J., Starkoff, B.E. & Devor, S.T. 2013. Crossfit-based Highintensity Power Training Improves Maximal Aerobic Fitness and Body Composition. The Journal of Strength & Conditioning Research, 27 (11): 3159-3172. https://doi.org/10.1519/jsc.0b013e318289e59f
Sprey, J.W., Ferreira, T., de Lima, M.V., Duarte Jr, A., Jorge, P.B. & Santili, C. 2016. An Epidemiological Profile of Crossfit Athletes in Brazil. Orthopaedic Journal of Sports Medicine, 4 (8). https://doi.org/10.1177/2325967116663706
Summitt, R.J., Cotton, R.A., Kays, A.C. & Slaven, E.J. 2016. Shoulder Injuries in Individuals who Participate in CrossFit Training. Sports Health, 8 (6): 541-546. https://doi.org/10.1177/1941738116666073
Tabata Times. 2014. How Fast are the CrossFit Games Growing? The Numbers Tell the Story. Retrieved from: https://web.archive.org/web/20140709055050/http://www.tabatatimes.com/how-fastare-the-crossfit-games-growing-the-numbers-tell-the-story/
Tang, S., Qian, X., Zhang, Y. & Liu, Y. 2016. Treating Low Back Pain Resulted from Lumbar Degenerative Instability Using Chinese Tuina Combined with Core Stability Exercises: a Randomized Controlled Trial. Complementary Therapies in Medicine, 25: 45-50. https://doi.org/10.1016/j.ctim.2016.01.001
Three Dimensional Physical Therapy. 30 July 2019. How to Improve Joint Range of Motion When Stretching Isn't Enough. Retrieved from https://3dpt.com/how-toimprove-joint-range-of-motion-when-stretching-isnt-enough/.
Weisenthal, B.M., Beck, C.A., Maloney, M.D., DeHaven, K.E. & Giordano, B.D. 2014. Injury Rate and Patterns among CrossFit Athletes. Orthopaedic Journal of Sports Medicine, 2 (4). https://doi.org/10.1177/2325967114531177
Aune, K.T. & Powers, J.M. 2017. Injuries in an Extreme Conditioning Program. Sports Health, 9 (1): 52-58. https://doi.org/10.1177/1941738116674895
Balf, C. 2019. 2020 CrossFit Open Registration Numbers Show Drop from 2019. Retrieved from: https://barbend.com/2020-crossfit-open-numbers/
Bandura, A. & Walters, R.H. 1977. Social Learning Theory (Vol. 1). US: Englewood Cliffs, NJ, Prentice-hall.
Bandy, W.D., Irion, J. M. & Briggler, M. 1998. The Effect of Static Stretch and Dynamic Range of Motion Training on the Flexibility of the Hamstring Muscles. Journal of Orthopaedic & Sports Physical Therapy, 27 (4): 295-300. https://doi.org/10.2519/jospt.1998.27.4.295
Bergeron, M.F., Nindl, B.C., Deuster, P.A., Baumgartner, N., Kane, S.F., Kraemer, W.J. & O'Connor, F.G. 2011. Consortium for Health and Military Performance and American College of Sports Medicine Consensus Paper on Extreme Conditioning Programs in Military Personnel. Current Sports Medicine Reports, 10 (6): 383-389. https://doi.org/10.1249/jsr.0b013e318237bf8a
Braun, V. & Clarke, V. 2006. Using Thematic Analysis in Psychology. Qualitative Research in Psychology, 3 (2): 77-101. https://www.tandfonline.com/doi/abs/10.1191/1478088706qp063oa
Cheatham, S.W., Kolber, M.J., Cain, M. & Lee, M. 2015. The Effects of Self-Myofascial Release Using a Foam Roll or Roller Massager on Joint Range of Motion, Muscle Recovery, and Performance: a Systematic Review. International Journal of Sports Physical Therapy, 10 (6): 827. https://pubmed.ncbi.nlm.nih.gov/26618062/
Claudino, J.G., Gabbett, T.J., Bourgeois, F., de Sá Souza, H., Miranda, R.C., Mezêncio, B. & Amadio, A.C. 2018. Crossfit Overview: Systematic Review and Metaanalysis. Sports Medicine-Open, 4 (11): 1-14. https://doi.org/10.1186/s40798-018-0124-5
Cosio, D. & Lin, E.H. n.d. Traditional Chinese Medicine Techniques. Retrieved from https://www.practicalpainmanagement.com/patient/treatments/alternative/6-traditional-chinese-medicine-techniques
Crockett, M.C. & Butryn, T. 2018. Chasing Rx: A spatial Ethnography of the CrossFit Gym. Sociology of Sport Journal, 35 (2): 98-107. https://doi.org/10.1123/ssj.2017-0115
CrossFit Level 1 Training Guide. 2019. CrossFit Inc.
CrossFit Inc. n.d. Official CrossFit Affiliate Map. Retrieved from https://map.crossfit.com/?_ga=2.60663213.102027535.1571933800-563792764.1570185148.
Dawson, M.C. 2017. CrossFit: Fitness Cult or Reinventive Institution?. International Review for the Sociology of Sport, 52 (3): 361-379. https://doi.org/10.1177%2F1012690215591793
Feito, Y., Burrows, E.K. & Tabb, L.P. 2018. A 4-Year Analysis of the Incidence of Injuries among CrossFit-Trained Participants. Orthopaedic Journal of Sports Medicine, 6(10). https://dx.doi.org/10.1177%2F2325967118803100
Fisher, J., Sales, A., Carlson, L. & Steele, J. 2016. A Comparison of the Motivational Factors between CrossFit Participants and Other Resistance Exercise Modalities: a Pilot Study. Journal of Sports Medicine and Physical Fitness, 57 (9): 1227-1234. https://doi.org/10.23736/s0022-4707.16.06434-3
Fletcher, J. 31 May 2018. Dry Needling vs. Acupuncture: Benefits and Uses. Retrieved from https://www.medicalnewstoday.com/articles/321989.php.
Fullagar, H.H., Skorski, S., Duffield, R., Hammes, D., Coutts, A.J. & Meyer, T. 2015. Sleep and Athletic Performance: the Effects of Sleep Loss on Exercise Performance, and Physiological and Cognitive Responses to Exercise. Sports Medicine, 45 (2): 161-186. https://doi.org/10.1007/s40279-014-0260-0
Hackney, R.G. 1994. Nature, Prevention, and Management of Injury in Sport (ABC of Sports Medicine. British Medical Journal, 308 (6940): 1356-1360. https://doi.org/10.1136/bmj.308.6940.1356
Hak, P.T., Hodzovic, E. & Hickey, B. 2013. The Nature and Prevalence of Injury during CrossFit Training. Journal of Strength and Conditioning Research, 22. https://doi.org/10.1519/jsc.0000000000000318
Heinrich, K.M., Patel, P.M., O’Neal, J.L. & Heinrich, B.S. 2014. High-Intensity Compared to Moderate-Intensity Training for Exercise Initiation, Enjoyment, Adherence, and Intentions: an Intervention Study. BMC Public Health, 14 (1): 789. https://doi.org/10.1186/1471-2458-14-789
Huzar, T. 28 March 2019. Does Cupping Therapy Work and What are the Benefits? Retrieved from https://www.medicalnewstoday.com/articles/324817.php.
Järvinen, M.J. & Lehto, M.U. 1993. The effects of Early Mobilisation and Immobilisation on the Healing Process Following Muscle Injuries. Sports Medicine, 15 (2): 78-89. https://doi.org/10.2165/00007256-199315020-00002
Järvinen, T.A., Järvinen, T.L., Kääriäinen, M., Äärimaa, V., Vaittinen, S., Kalimo, H. & Järvinen, M. 2007. Muscle Injuries: Optimising Recovery. Best Practice & Research Clinical Rheumatology, 21 (2): 317-331. https://doi.org/10.1016/j.berh.2006.12.004
Keogh, J.W. & Winwood, P.W. 2017. The Epidemiology of Injuries Across the Weight-Training Sports. Sports Medicine, 47 (3): 479-501. https://doi.org/10.1007/s40279-016-0575-0
Klimek, C., Ashbeck, C., Brook, A.J. & Durall, C. 2018. Are Injuries More Common with CrossFit Training than Other Forms of Exercise?. Journal of Sport Rehabilitation, 27 (3): 295-299. https://doi.org/10.1123/jsr.2016-0040
Kraemer, W.J., Adams, K., Cafarelli, E., Dudley, G.A., Dooly, C., Feigenbaum, M.S. & Newton, R.U. 2002. American College of Sports Medicine. American College of Sports Medicine Position Stand. Progression Models in Resistance Training for Healthy Adults. Medicine & Science in Sports & Exercise, 34 (2): 364-80. https://doi.org/10.1249/mss.0b013e3181915670
Kuhn, S. 2013. The Culture of CrossFit: A Lifestyle Prescription for Optimal Health and Fitness. Senior Theses. United States: Illionis State University.
Langdridge, D. 2004. Introduction to Research Methods and Data Analysis in Psychology. Harlow: Pearson Education.
Lei, F., Min, F., Shichao, J. & Hua, C. 2015. Optimization of Parameters of Yi Zhi Chan Tuina Manipulation Promotes Peripheral Circulation. Journal of Traditional Chinese Medicine, 35 (5): 558-563. http://dx.doi.org/10.1016/S0254-6272(15)30139-4
Gagnon, P. & Long, Z. 2019. Skills Progression Chart, The Barbell Physio. Retrieved from http://bit.ly/tbpchart
Ganfield, L. 2009. Myofascial Release Therapy- SPINE-Health. Available from https://www.spine-health.com/treatment/physical-therapy/myofascial-release-therapy
Maslow, A.H. 1943. A Theory of Human Motivation. Psychological Review, 50 (4): 370-396. https://psycnet.apa.org/doi/10.1037/h0054346
Mehrab, M., de Vos, R.J., Kraan, G.A. & Mathijssen, N.M. 2017. Injury Incidence and Patterns among Dutch CrossFit Athletes. Orthopaedic Journal of Sports Medicine, 5 (12), 2325967117745263. https://doi.org/10.1177/2325967117745263
Meyer, J., Morrison, J. & Zuniga, J. 2017. The Benefits and Risks of CrossFit: a Systematic Review. Workplace Health & Safety, 65 (12): 612-618. https://doi.org/10.1177/2165079916685568
Montalvo, A.M., Shaefer, H., Rodriguez, B., Li, T., Epnere, K. & Myer, G.D. 2017. Retrospective Injury Epidemiology and Risk Factors for Injury in CrossFit. Journal of Sports Science & Medicine, 16 (1): 53-59. https://pubmed.ncbi.nlm.nih.gov/28344451/
Mullins, N. 2015. CrossFit: Remember what You Have Learned: Apply What You Know. Journal of Exercise Physiology Online, 18 (6): 32-44. https://www.researchgate.net/publication/290123696_CrossFit_Remember_what_you_have_learned_apply_what_you_know
Paine, J., Uptgraft, J. & Wylie, R. 2010. CrossFit Study. Fort Leavenworth: Command and General Staff College. http://library.crossfit.com/free/pdf/CFJ_USArmy_Study.pdf
Parkkari, J., Kannus, P., Natri, A., Lapinleimu, I., Palvanen, M., Heiskanen, M. & Järvinen, M. 2004. Active Living and Injury Risk. International Journal of Sports Medicine, 25 (3): 209-216. https://doi.org/10.1055/s-2004-819935
Physiopedia. n.d. Rehabilitation in Sport. Retrieved from https://www.physiopedia.com/Rehabilitation_in_Sport
Poland, B.D. 2002. Transcription Quality. In J.F. Gubrium and J.A. Holstein (eds), Handbook of Interview Research: Context & Method. CA: Sage.
Reynolds, G. 2008. Stretching: the Truth. The New York Times. https://www.nytimes.com/2008/11/02/sports/playmagazine/112pewarm.html
Robertson, E. 2017. CrossFit's Dirty Little Secret. Retrieved from https://www.huffpost.com/entry/crossfitrhabdomyolysis_b_3977598?utm_hp_ref=mostpopular.
Ross, B. 2018. The Controversy behind CrossFit. Retrieved from https://www.livestrong.com/article/545200-the-fall-of-fitness/.
Safran, M.R., Garrett, W.E., Seaber, A.V., Glisson, R.R. & Ribbeck, B.M. 1988. The role of Warmup in Muscular Injury Prevention. The American Journal of Sports Medicine, 16 (2): 123-129. https://doi.org/10.1177/036354658801600206
Schneider, N.C., Coates, W. C. & Yarris, L.M. 2017. Taking Your Qualitative Research to the Next Level: a Guide for the Medical Educator. AEM Education and Training, 1 (4): 368-378. https://dx.doi.org/10.1002%2Faet2.10065
Schroeder, A.N. & Best, T.M. 2015. Is Self Myofascial Release an Effective Preexercise and Recovery Strategy? A Literature Review. Current Sports Medicine Reports, 14 (3): 200-208. https://doi.org/10.1249/jsr.0000000000000148
Simmons, E. 2014. Why I don't do CrossFit. Retrieved from https://www.huffpost.com/entry/why-i-dont-docrossfit_b_5411771?guccounter=1&guce_referrer=aHR0cHM6Ly93d3cuZ29vZ2xlLmNvbS8&guce_referrer_sig=AQAAABhYnVHT_0s4Gnd_vsPEYxydlnXW3-HLjtxK-kTKaNWDr21NlIfgfEEVVfkFZlbFuBgHHzN10_Fyh8wigV_3MVKwRlBfqesBGmJWQVGt5nYSXMbKbWFSSUYlycH0LLeOBZ4qxrRsR46dKKfKsl8Ww80QJ7Rz6zhOOgBmIXbQil.
Smith, M.M., Sommer, A.J., Starkoff, B.E. & Devor, S.T. 2013. Crossfit-based Highintensity Power Training Improves Maximal Aerobic Fitness and Body Composition. The Journal of Strength & Conditioning Research, 27 (11): 3159-3172. https://doi.org/10.1519/jsc.0b013e318289e59f
Sprey, J.W., Ferreira, T., de Lima, M.V., Duarte Jr, A., Jorge, P.B. & Santili, C. 2016. An Epidemiological Profile of Crossfit Athletes in Brazil. Orthopaedic Journal of Sports Medicine, 4 (8). https://doi.org/10.1177/2325967116663706
Summitt, R.J., Cotton, R.A., Kays, A.C. & Slaven, E.J. 2016. Shoulder Injuries in Individuals who Participate in CrossFit Training. Sports Health, 8 (6): 541-546. https://doi.org/10.1177/1941738116666073
Tabata Times. 2014. How Fast are the CrossFit Games Growing? The Numbers Tell the Story. Retrieved from: https://web.archive.org/web/20140709055050/http://www.tabatatimes.com/how-fastare-the-crossfit-games-growing-the-numbers-tell-the-story/
Tang, S., Qian, X., Zhang, Y. & Liu, Y. 2016. Treating Low Back Pain Resulted from Lumbar Degenerative Instability Using Chinese Tuina Combined with Core Stability Exercises: a Randomized Controlled Trial. Complementary Therapies in Medicine, 25: 45-50. https://doi.org/10.1016/j.ctim.2016.01.001
Three Dimensional Physical Therapy. 30 July 2019. How to Improve Joint Range of Motion When Stretching Isn't Enough. Retrieved from https://3dpt.com/how-toimprove-joint-range-of-motion-when-stretching-isnt-enough/.
Weisenthal, B.M., Beck, C.A., Maloney, M.D., DeHaven, K.E. & Giordano, B.D. 2014. Injury Rate and Patterns among CrossFit Athletes. Orthopaedic Journal of Sports Medicine, 2 (4). https://doi.org/10.1177/2325967114531177
