It is well known that women are more likely to sustain certain connective tissue injuries than men during physical activities (Jones et al. 1993; Bijur et al. 1997). Females injure their ACL (anterior cruciate ligament) in their knees of 4-6 times more frequently than men. Females experience more ankle injuries, overuse wrist injuries and stress fractures than males (Ristolainen, 2009).
A review of 1,382 original research articles from 3 sports and exercise medicine Journals over a 3-year period between 2011 and 2013 included 6,076,580 participants (Taunton et al., 2002). The average percentage of female participants per article across the journals ranged from 35% to 37%. This raise the question of whether or not injury and rehab conclusion gained from the research can be equally applied to females.
Many factors can influence injury including external factors such as type of sport, equipment used, environmental issues, conditioning, experience, and skill of the athlete. Internal factors related to injury include ligamentous laxity, hormonal influences, biomechanical alignment, skeletal features.
In this article we unpack research looking at responses to exercise and rest and their impact on the strength of tendons and ligaments and how this different between males and females. This information may impact training progressions between genders.
Strength training results do not produce the same effects in men and women. Magnusson et al. found that habitual training resulted in a larger patellar tendon in men but not in women. Women have a lower rate of new connective tissue formation in tendon tissue, respond less to mechanical loading, and have a lower mechanical strength of isolated collagen fascicles, which may leave the tissue more susceptible to injury (Magnusson, 2007).
Estrogen was found to inhibit the acute exercise-related increase in tendon collagen synthesis. In women there was no difference shown in gross magnitude of Achilles and patellar tendons between trained and untrained females. The Findings in males were in line with common beliefs that trained subjects do demonstrate larger tendons than untrained males (Kjaer & Hansen, 2008)
However, at rest, Estrogen does appear to have a stimulating effect on tendon collagen synthesis. During inactivity prolonged inactivity women are more resistant to losing their supportive tendon structure.
Considering these finding that Estrogen appears to have a diminishing effect on exercise response to collagen syntheses but an enhancing effect of stimulating collagen at rest females might consider that they may adapt slower than males to training and should take this into account in designing their training programs in order to minimise the incidence of injuries and allows adequate rest built into training progressions.
Furthermore, research comparing females using oral contraceptives to females not on the pill, found further insights on the impact of estrogen. Women on the pill typically maintain estradiol levels at ∼25 pg/ml and decrease the ovulatory rise in estrogen (Mishell et al., 1972). This daily dose of estrogen and or progesterone also eliminates the cyclic rise in LH and FSH (Chidi-Ogbolu & Baar, 2019).
However, during the early follicular phase of the menstrual cycle women have significant drop in estrogen to levels, lower than the continuous does of estrogen offered in oral contraceptives. The women in the non-pill group tested during this phase of the menstrual cycle responded to the acute bout of exercise with an elevated collagen synthesis compared to compared to the group taking oral contraceptives. These data further the idea that estradiol can influence collagen metabolism by reducing the acute exercise induced response of collagen synthesis. It also may indicate that females should train relatively more during this phase of their cycle and rest more just prior to ovulation when their estrogen levels are at a peak. (Chidi-Ogbolu & Baar, 2019)
References:
Barrack MT, Gibbs JC, De Souza MJ, et al. Higher incidence of bone stress injuries with increasing female athlete triad-related risk factors: a prospective multisite study of exercising girls and women [published online February 2014]. Am J Sports Med.
Bennell K, Matheson G, Meeuwisse W, Brukner P. Risk factors for stress fractures. Sports Med. 1999;28:91-122.
Ristolainen, Leena, et al. “Gender differences in sport injury risk and types of injuries: a retrospective twelve-month study on cross-country skiers, swimmers, long-distance runners and soccer players.” Journal of sports science & medicine 8.3 (2009): 443.
Chidi-Ogbolu, N., & Baar, K. (2019). Effect of Estrogen on Musculoskeletal Performance and Injury Risk. Frontiers in Physiology, 9(1834). doi:10.3389/fphys.2018.01834
Kjaer, M., & Hansen, M. (2008). The mystery of female connective tissue. J Appl Physiol (1985), 105(4), 1026-1027. doi:10.1152/japplphysiol.91008.2008
Magnusson, S. P. (2007). The adaptability of tendon to loading differs in men and women (Vol. 88). International Journal of Experimental Pathology.
Taunton, J. E., Ryan, M. B., Clement, D. B., McKenzie, D. C., Lloyd-Smith, D. R., & Zumbo, B. D. (2002). A retrospective case-control analysis of 2002 running injuries. Br J Sports Med, 36(2), 95-101. doi:10.1136/bjsm.36.2.95
Comments