This article was written by one of our regular contributors; PhD student and founder of women’s health and performance in sport & exercise educational platform The Period of the Period – Kelly McNulty.
Anterior cruciate ligament (ACL) injuries, bone stress injuries, and concussions are all common sports injuries that occur in both males and females . It’s well understood that these injuries are a concern for all individuals in terms of time away from training or competing (or causing drop out and/or even ending careers entirely), long-term health effects, as well as financial costs. Even for those of us who are not competing at athlete level, injuries can have huge knock on effects to both our physical health and mental health – and social lives. Therefore, reducing the risk of sporting injuries and improving treatment for these injuries will have a major impact on sports participation, performance, and long‐term quality of life. But, whilst we recognise that these sports injuries are common and cause concern, less commonly recognised are the potential sex specific differences in prevalence, risk factors, and outcomes of these injuries. So, let’s dive in!
*Please note that sex differences relate to biological factors including X and Y gene expression, anatomy, and hormones, whereas gender is associated with societal behaviours and cultural factors. It’s important to highlight that it’s not always easy to separate the impact of sex and gender on sports injuries as they are often entangled and influence each other .
Anterior cruciate ligament injuries
The ACL is one of the major ligaments in the knee and plays an important role in the stabilisation of it. ACL injuries are one of the most sustained injuries in sports, particularly those involving contact or repetitive change of directions, such as rugby, football, and skiing. Interestingly, research investigating non-contact ACL injuries highlights that women and girls are at particularly high risk for ACL injuries with rates 3 to 6 times greater than men ! Despite this, the reasons for these sex differences in ACL injury risk are not well-known (usual caveat: we need more research!). However, various researchers have suggested differences in anatomy (i.e., a wider pelvis, which alters the alignment of the knee and ankle, although scientific evidence supporting this is limited), hormonal (i.e., the fluctuations in sex hormones across a female’s lifespan might influence risk. For example, it’s thought that the menstrual cycle might influence ACL injury risk with a recent review highlighting increased ligament laxity and ACL injury in the ovulatory phase of the menstrual cycle, but further high-quality research is needed ), and neuromuscular function (i.e., muscle imbalances and technique, such as landing mechanics) as potential reasons for the higher injury risk in women than men.
Bone stress injuries
Bone stress injuries are overuse injuries to bone that commonly occur in individuals who take part in repetitive exercise, such as regular gym work, as well as running activities. Whilst these injuries occur in both males and females, research reports that females are especially at risk, with bone stress injuries more common in females . Whilst the literature highlights that a lot of the risk factors for bone stress injuries are shared between males and females, including previous injury, age, participation in ‘lean’ sports (i.e., cross-country running and gymnastics), low body mass index, reduced dietary calcium and vitamin D intake and relative energy deficiency in sport (i.e., inadequate energy intake to meet the demands of sport and day-to-life contributes to impaired bone health and injury risk) , there are some risk factors specific to females. For example, research suggests that late menarche (i.e., first period occurring after 15 years old), irregular or absent periods and menopause (i.e., menopause is associated with an increased risk of injury, as oestrogen declines) can all influence bone stress injuries . To learn more about protecting your bone health see here.
A concussion is a form of traumatic brain injury which is characterised by pathophysiological alterations affecting brain function and are mostly reported in collision and contact sports. Again, although these injuries can happen to both sexes, research highlights that females are more susceptible to sport-related concussions and tend to have more severe and prolonged symptoms when compared to males [6-7], but interpreting these data can be difficult as both males and females tend to under-report symptoms. Additionally, it’s also of interest to note that this research shows that females are more likely to sustain a concussion due to contact with an object or the ground, whereas males ten to sustain a concussion due to player contact [6-7]. Possible factors that put females at this higher risk for concussions and worse outcomes, include anatomy and biomechanical differences (i.e., females have smaller head size and have less neck musculature to protect the head during impacts [6-7]) and hormonal differences (i.e., research reports that females who sustained a concussion during the follicular phase or were on hormonal contraception had better outcomes than those who sustained their injury in the luteal phase ), although again – you guessed it – further research is needed.
Despite sex-based differences being apparent in common sports injuries, females remain an understudied population resulting in a lack of sex-specific prevention and treatment guidelines. Therefore, to be able to effectively prevent, diagnose, and treat these common sports injuries in females, more research is required. That said, an important first step in preventing injuries is educating yourself on these sex differences in injury risk factors and what you can do to reduce them, based on the information we do have! Additionally, practitioners and medical staff should be aware that instead of applying a one-size-ﬁts-all prevention and treatment approach to these injuries, managing these injuries with an understanding of the sex-speciﬁc differences might help to optimise an individual’s recovery. Overall, injuries result from a multitude of factors which are often interlinked, therefore you’re not going to get an injury solely because of your sex, but it might be a contributing factor. As such, having an awareness of this can keep you participating in sport injury-free or get you back to the activity you love quickly and effectively post-injury.
- Lin, C. Y., Casey, E., Herman, D. C., Katz, N., & Tenforde, A. S. (2018). Sex differences in common sports injuries. PM&R, 10(10), 1073-1082.
- Parsons, J. L., Coen, S. E., & Bekker, S. (2021). Anterior cruciate ligament injury: towards a gendered environmental approach. British Journal of Sports Medicine.
- Hewett, T. E., Zazulak, B. T., & Myer, G. D. (2007). Effects of the menstrual cycle on anterior cruciate ligament injury risk: a systematic review. The American Journal of Sports Medicine, 35(4), 659-668.
- Herzberg, S. D., Motu’apuaka, M. L., Lambert, W., Fu, R., Brady, J., & Guise, J. M. (2017). The effect of menstrual cycle and contraceptives on ACL injuries and laxity: a systematic review and meta-analysis. Orthopaedic Journal of Sports Medicine, 5(7), 2325967117718781.
- Wentz, L., Liu, P. Y., Haymes, E., & Ilich, J. Z. (2011). Females have a greater incidence of stress fractures than males in both military and athletic populations: a systematic review. Military Medicine, 176(4), 420-430.
- McGroarty, N. K., Brown, S. M., & Mulcahey, M. K. (2020). Sport-related concussion in female athletes: A systematic review. Orthopaedic Journal of Sports Medicine, 8(7), 2325967120932306.
- Sanderson, K. (2021). Why sports concussions are worse for women. Nature, 596, 26-28.
- Wunderle, M. K., Hoeger, K. M., Wasserman, M. E., & Bazarian, J. J. (2014). Menstrual phase as predictor of outcome after mild traumatic brain injury in women. The Journal of Head Trauma Rehabilitation, 29(5), E1.