Knees, Hormones and Women's Health: A Traditional Chinese Medicine Perspective
Why are teenage girls more vulnerable to ACL injuries and what do the Kidneys, Liver, menstruation, nutrition and keeping warm have to do with knee health?
In clinic, I treat a lot of sports injuries and recently I've been treating a teenage footballer recovering from an anterior cruciate ligament (ACL) tear in her knee. As you can imagine, for a young, active girl who loves her football, an injury like this can be incredibly frustrating. There's the pain, swelling and stiffness but also the emotional side of being unable to do something she loves.
She's receiving physiotherapy to rebuild muscle strength and stability around her knee and I've been supporting her recovery with acupuncture and electroacupuncture. It's also got me thinking about something I find particularly interesting. Why are teenage girls and women more vulnerable to ACL injuries in sports such as football and could there be a connection with their hormonal health?
Research has shown that teenage girls playing sports such as football and basketball experience higher rates of ACL injuries than boys participating in the same sports. A systematic review published in Arthroscopy in 2025 found that adolescent female athletes had a 1.56 times greater overall risk of ACL injury than their male counterparts across the sports studied.
There are several possible explanations for this, including anatomical differences, biomechanics, muscle strength, movement patterns and hormonal influences. The role of hormonal fluctuations throughout the menstrual cycle is attracting increasing attention, although research has yet to establish a consistent relationship between particular phases of the cycle and ACL injury risk.
What I find particularly interesting is that Traditional Chinese Medicine (TCM) has long considered women's reproductive health, nourishment and musculoskeletal wellbeing to be interconnected. From a TCM perspective, there is a fascinating relationship between the knees, the Kidneys, the Liver, menstruation and the importance of keeping the body well nourished and warm.
The relationship between the Kidneys, Liver and knee health
In Chinese medicine, the Kidneys are considered the foundation of our constitutional vitality. They store Jing, or Essence, which is traditionally associated with growth, development, reproduction and ageing. The Kidneys are also said to govern the bones and have a particularly close relationship with the knees and lower back. This doesn't simply refer to our anatomical kidneys but to a much broader functional system within Chinese medicine.
The Kidneys are also considered fundamental to reproductive health, particularly the development and regulation of the menstrual cycle. When I see someone with knee problems, I therefore don't necessarily think only about the joint itself. I'm also interested in their overall constitution, energy levels, recovery, diet and, where relevant, their menstrual health.
The Liver is another important organ system in Chinese medicine and is said to store Blood and nourish the sinews, a traditional term encompassing tendons and ligaments. Blood is considered essential for nourishing the tissues and maintaining flexibility and healthy movement, while Qi and Yang provide the movement and warmth needed for healthy function. When nourishment is insufficient, TCM describes patterns such as Blood Deficiency, which may be associated with fatigue, muscle tightness, cramping or a feeling of weakness.
When an injury occurs, we often describe the resulting pain, swelling and restricted movement through patterns such as Qi and Blood stagnation. These are traditional Chinese medicine concepts rather than direct equivalents of modern medical diagnoses but they help explain why I take a wider view when supporting someone with a musculoskeletal injury.
Menstruation, Blood and the importance of nourishment
One aspect of women's health that I feel deserves more attention is the importance of nourishment throughout the menstrual cycle, particularly during the teenage years. At this stage, the body is still growing and developing while often juggling the demands of school, sport and busy social lives. Add monthly menstruation into the mix and adequate nutrition becomes even more important.
In Traditional Chinese Medicine, menstruation is closely connected to the Kidneys, Liver and two extraordinary channels known as the Chong Mai and Ren Mai. The Chong Mai is traditionally known as the Sea of Blood while the Ren Mai is associated with reproductive health. Together, these systems are considered important in regulating the menstrual cycle and maintaining the body's natural rhythms.
From a TCM perspective, maintaining and replenishing Blood is essential for nourishment and vitality. This is particularly relevant for teenage girls who are training regularly and need sufficient nutrition to support their growth, recovery and menstrual health.
Of course, menstruation doesn't automatically lead to deficiency and TCM Blood Deficiency is different from medically diagnosed iron deficiency. However, menstruating girls have increased iron requirements and heavier periods can increase the risk of deficiency, particularly when nutritional intake is inadequate.
It does make me wonder: Are we doing enough to teach young girls how to nourish their bodies throughout their cycle, especially when they're training hard and leading such busy lives?
What I'm seeing with teenage girls in clinic
Something I notice quite frequently in clinic is that many teenage girls simply aren't eating the sort of substantial, nourishing meals that I would love to see them having. And this is often despite their parents' very best efforts and, I'm sure, quite a lot of nagging along the way! Between school, homework, sport, socialising and everything else going on in their lives, it's easy for meals to become rushed, skipped or replaced with quick snacks.
I also notice a tendency towards cold foods, smoothies, salads or meals grabbed on the go. Of course, these foods can be part of a perfectly healthy diet but from a Chinese medicine perspective, I like to encourage warm, cooked and nourishing meals, particularly for girls who are growing, menstruating and training regularly. Warming porridge in the morning, homemade soups, nourishing stews, lentils, beans, eggs, fish, meat or tofu, cooked vegetables and plenty of healthy carbohydrates are all examples of foods that can provide valuable nourishment.
In TCM dietary theory, warm and cooked foods are traditionally considered supportive of the Spleen and Stomach systems, which are responsible for transforming food into Qi and Blood. The emphasis is on supporting digestion and providing the body with the nourishment it needs. This doesn't mean that cold or raw foods are unhealthy or that eating them causes knee injuries. Rather, I believe there is value in encouraging girls to eat regular, substantial meals and understand why nourishing their bodies matters.
I think we should also be teaching girls much more about eating to support their menstrual cycles. Not through restrictive diets or complicated rules about what to eat on particular days but by helping them understand the importance of adequate energy, iron, protein, carbohydrates and other essential nutrients throughout the month. Their bodies are not only recovering from exercise but are still growing and developing.
Modern sports nutrition recognises the importance of adequate fuelling too. When young athletes consistently consume less energy than their bodies need, it can affect hormonal function, bone health and recovery. This is sometimes described as Relative Energy Deficiency in Sport, or REDs. It is particularly important that girls who are training regularly understand the value of eating enough rather than feeling pressure to restrict their food intake.
For me, the message is simple. Teenage girls need to be properly nourished, not just for their sport but for their growth, menstrual health and general wellbeing. Eating well isn't simply about having enough energy for today's training session. It's about supporting their bodies throughout the month and for the years ahead.
Cold knees, bare midriffs and the importance of keeping warm
Another thing I notice, particularly with teenagers, is how often their knees, lower backs and midriffs are exposed to the cold. Whether it's playing football in shorts on a freezing winter's day, wearing cropped tops or wandering around with bare ankles, keeping warm doesn't always seem to be high on the priority list!
From a Chinese medicine perspective, this is something I pay attention to. In TCM, Cold is traditionally considered a factor that can obstruct the smooth movement of Qi and Blood. It is associated with contraction, restricted movement, stiffness and certain patterns of joint discomfort. Blood is said to nourish the tissues while Yang energy provides warmth, helping the body maintain comfortable movement and function.
The Kidneys and lower back also have a particularly close relationship in Chinese medicine. Kidney Yang is traditionally associated with the body's warming functions, so protecting the lower back from cold is a longstanding principle within TCM. When someone is already experiencing fatigue or a pattern of deficiency, Chinese medicine places additional importance on supporting warmth and nourishment.
Interestingly, women's core body temperatures also fluctuate slightly throughout the menstrual cycle, largely in response to changes in progesterone. From a TCM perspective, I find this another fascinating reason to consider a woman's individual experience of warmth, energy and comfort throughout the month. These normal temperature fluctuations are not themselves evidence of an increased risk of knee injury but they remind us that the female body is constantly adapting to its natural hormonal rhythms.
This is why I encourage my younger patients to think about simple things such as keeping warm before and after sport, changing out of cold or damp clothing and protecting their lower backs and knees during colder weather. Of course, there is no good scientific evidence that exposed knees, bare midriffs or cold weather directly cause ACL tears. However, within TCM, maintaining warmth is an important part of looking after the body's comfort and balance.
Personally, I think a little more warmth, a good nourishing meal and sufficient recovery time are sensible things to encourage, particularly during our colder months.
How acupuncture and electroacupuncture can support knee recovery
When treating sports injuries, my aim is to support the whole person throughout their recovery rather than simply focusing on the injured area. With electroacupuncture, I use gentle electrical pulses through acupuncture needles to provide a more sustained level of stimulation. From a Chinese medicine perspective, the intention is to encourage the movement of Qi and Blood, address stagnation and support the nourishment of the surrounding sinews.
Electroacupuncture may offer additional support in managing pain and some symptoms associated with knee injuries, although research specifically relating to ACL rehabilitation remains limited. It's important to understand that acupuncture does not repair a torn ACL or replace the strengthening and rehabilitation needed following an injury.
With the teenage footballer I'm treating, acupuncture is only one part of her recovery. She's also receiving physiotherapy to strengthen the muscles around her knee, improve stability and movement and gradually rebuild the strength and confidence she'll need to return to football safely. For me, these approaches can work alongside one another, with physiotherapy addressing the physical demands of rehabilitation and acupuncture potentially providing additional symptom relief and support for her wider wellbeing.
Looking after our knees and the whole person
I think one of the most valuable aspects of Chinese medicine is that it encourages us to look beyond the site of an injury. A painful knee is not simply a knee. It's part of a person whose health and recovery are influenced by activity levels, nutrition, sleep, stress and overall wellbeing.
For teenage girls, I feel we should be paying much more attention to menstrual health, adequate nourishment and the importance of supporting their changing bodies. Research into the higher rates of ACL injuries among female athletes is continuing and we cannot say that menstrual fluctuations, exposure to cold or TCM patterns of deficiency are responsible for these injuries. However, Chinese medicine offers a complementary perspective that encourages us to think about the wider person and the importance of warmth, nourishment and balance.
If there's one thing I'd love more young girls to understand, it's that their bodies need to be fuelled, nourished and supported, particularly when they're growing, menstruating and playing competitive sport. Helping them develop these habits early in life can be valuable for their long-term health and wellbeing.
And sometimes, a little extra knee-dling can be one supportive part of that journey too!
Nickila x