Anterior cruciate ligament (ACL) and hamstring injuries are not only prevalent in women’s sports of all levels but are also rising alongside the increase in women’s sport participation. ACL injuries are particularly devastating, requiring up to 12-24 months recovery. Combined with the average cost of ACL reconstructions being around £4000-£8000, these injuries put a considerable burden on NHS resources, negatively affecting both the mental and physical health of patients and potentially leading to long-term complications like arthritis.
Most ACL injuries are non-contact and stem from the athlete’s natural movements, involving the interaction of the hip, knee and ankle joints, such as landing badly or changing direction. These challenges are even greater for women athletes, as their unique physiological characteristics are often poorly understood. For example, women have wider pelvises compared to men, which comes with its own physiological challenges and leads to a higher risk of ACL injury. To address this growing issue, innovations like smart leggings—easy-to-use garments with built-in monitoring technology—have been developed to provide better insights and solutions for reducing injury risks.
The rising challenge of women’s sports injuries
Women are up to 3-6 times more at risk of non-contact ACL injuries compared to men. The reasons for this are poorly understood due to the challenges in accurately measuring lower limb movement, from the hips to the ankles, outside laboratory settings. Recently, women’s elite football has received high-profile media attention, driving many scientists to investigate this issue. One such investigation found hamstring injuries were the most frequent, whilst ACL injuries had the highest burden in terms of recovery time.
Evidence suggests that muscle imbalances in the lower limb —both in terms of muscle thickness (hypertrophy) and neuromuscular activation (the electrical signals that cause muscle contraction)— can increase both ACL and/or hamstring injury risk. However, there is evidence to suggest that we can reduce these risks.
Weakness in gluteal muscles can shift the alignment of the pelvis and thigh bone, which may cause the knee to collapse inward during movement, a condition known as dynamic knee valgus. This inward knee movement is a key factor linked to ACL injuries, particularly in women. Studies have shown that female athletes tend to exhibit more pronounced knee valgus during activities like squats, landing, and running compared to male athletes, increasing their risk of such injuries.
Injuries are caused by many different factors, but most previous studies have focused on just one in a laboratory setting. This makes it harder to understand how women’s movement patterns differ from men’s in continuous match-play and real-world training environments.
Currently, the study and measuring of movement is restricted to laboratory-based motion capture systems. These camera and marker systems are time-consuming to set up, disrupt athlete training schedules, and remove athletes from realistic sporting scenarios. To close this knowledge gap, we need to look at multiple factors together, including joint movement, nerve and muscle coordination, muscle size, and strength, all within the same group of people in one study.
New monitoring technologies have been developed to capture movement quality in real-world sporting scenarios and improve our knowledge of injuries in women’s sports.
Smart leggings: A game-changer for injury prevention research
Smart leggings are designed to fit and feel like regular sportswear while integrating discreet sensors to measure joint angles, speed, and direction. Users report these sensors are virtually undetectable when worn.
Early findings show the data collected from smart leggings is comparable to gold-standard motion capture systems, but with increased practicality. These garments are washable, scalable for mass production and are sustainable by design – allowing for dismantling and repurposing of their components.
This technology isn’t limited to improving athlete performance and preventing injuries, it also has huge potential in healthcare. Smart leggings can be tailored to patients in their recovery after a stroke, hip replacement, or knee surgery. This can help doctors and therapists guide patients through safer and more effective recoveries.
Another application tracks movement and provides feedback through a phone app, enabling users to monitor their movements, exercise safely, and stay active while reducing the risk of pain or injury. This is especially important for older women who often experience more pain and injuries during everyday activities, and may lose confidence in moving and exercising. Staying active as we age boosts happiness, mental health, bone strength, and muscle health while helping prevent and control conditions like Type 2 diabetes and high blood pressure.
This research aims to enable a better understanding of women-specific injury risks by measuring activity in real-world scenarios and revealing the body’s mechanics and movements that contribute to these risks. Identifying the key, modifiable risk factors will enable the design and testing of prescriptive training interventions that could mitigate injury risk for women athletes. This will positively impact the lives of women of all ages. By investing in female-centric technology, we will help to close the gender gap that currently exists in health research.
Lucinda Abell Black
Lucinda Abell Black is a recipient of the prestigious Industrial Fellowship from the Royal Commission for the Exhibition of 1851, which supports the development of cutting-edge technologies to position the UK as a global leader in science and engineering. She works with KYMIRA Ltd, a leading electronic-textiles company, and Loughborough University, to bridge academia and industry, ensuring her research delivers real-world impact.
