Most of the research in sport and exercise medicine has been geared towards men, but attention in women’s sport is changing the game.
Kathy Skantzos reports
All eyes have been on women’s elite sports this year, with the frenzy over the Matildas in the Women’s World Cup and a string of women’s world-league events in cycling, tennis, rugby, golf and cricket.
When it comes to research in sport and exercise medicine, women have largely been left on the sidelines. Female athletes, their coaches and physicians have relied mostly on anecdotal reports and science focused on male athletes to navigate performance and injury in women’s elite sport.
Dr Carmel Goodman, sport and exercise medicine physician and chief medical officer for the Western Australian Institute of Sport (WAIS), says the research on female athletes is starting to catch up only now.
“Men’s sport has always been rated as much more important than women’s sport. It’s only been as women’s sport has become more popular that the money and interest has gone into research,” she said.
Dr Goodman has worked with elite athletes over her expansive three-decade career, including being a long-time physician for the Hockeyroos and Rowing Australia and a team doctor at the Olympic and Commonwealth Games since 2000.
Emerging research is uncovering how the menstrual cycle is a significant factor on physical performance, psychological stress, mental focus, and rates of injury among elite female athletes.
“We know that athletes are performing at their worst a few days premenstrual because they’re feeling fatigued,” Dr Goodman said.
Fluctuating fortunes
Hormonal changes at various times of the menstrual cycle, particularly during the premenstrual and menstrual phases, can alter mood, motivation, focus and sleep, and can bring on cramps, pain, inflammation, muscle soreness, stress, and fatigue.
Every elite female football player involved in a 2021 interview-based study said changes in their menstrual cycle negatively impacted their competitive performance, noting fatigue, impaired strength, lower confidence and reduced focus, particularly during menstruation.
A 2022 systematic review with meta-analysis showed changes in motivation and competitiveness during the menstrual cycle and better outcomes in the ovulation phase compared to follicular and luteal phases. The review showed an increase in mood disturbance in the premenstrual phase (versus mid-cycle), decreased vigour during menses (versus luteal phase), increased menstrual symptoms in the follicular phase (versus ovulation), increased fatigue and decreased sleep quality in the luteal phase (versus follicular).
Female athletes reported their sport performance was particularly worse during the early follicular and late luteal phases. During the luteal phase (post-ovulation before the next cycle begins), after oestrogen levels peak and then drop as progesterone levels rise, women can typically feel more mentally and physically tired, with higher progesterone causing low energy and low mood.
A 2021 study in Medicine & Science in Sport & Exercise found that in a 20-minute cycling time trial, active women had lower performance and higher fatigue during the luteal phase.
Menstrual tracking
Tracking menstrual cycles has only recently been introduced to leading sports institutes to help female athletes, their coaches and medical practitioners understand how to avoid injury and fatigue and
improve performance.
WAIS started menstrual cycle tracking as part of its injury reporting system earlier this year as a recent addition to Australia-wide medical records.
“It’s only been the last four or five months that the menstrual cycle tracking has been added to day-to-day tracking. Prior to that we never tracked the female menstrual cycle,” Dr Goodman says.
WAIS uses the menstrual tracking data to modify training and reduce injury.
“Every new female athlete that comes to WAIS needs to record their menstrual cycle and every few months when they do their medical review, we see if it correlates with injury and illness, and we share that information with the coaches who are advised to reduce vigorous exercise when hormonal symptoms arise to avoid injury.
“We’re recognising more and more that mental and physical performance is certainly affected at different times of the menstrual cycle and that is something that has previously not been taken into account.”
Common injuries in women
Research published in the BMJ suggests women have higher rates of concussion compared with men, and Dr Goodman adds that women can take longer to recover.
“We don’t know if it’s related to hormonal changes because no one has done enough research to determine it,” Dr Goodman said.
A preliminary study showed that while progesterone is shown to be neuroprotective against concussion, women injured during the luteal phase of their menstrual cycle, when progesterone is highest, had worse post-concussion symptoms possibly due to the sudden drop in the hormone after injury.
As well as concussion, women athletes are more prone to anterior cruciate ligament (ACL) tears at certain times of their menstrual cycle and Dr Goodman said this
was another line of inquiry.
For elite female cyclists, who now have European grand tours on their competitive calendar, saddle sores and UTIs are common in greater number than male cyclists.
Dr Goodman says around 40% of female athletes are on the pill for contraceptive reasons, and about 60% are taking it to control their cycle and reduce the severity of premenstrual symptoms.
“We can modify training but that doesn’t help us when it’s competition time. What we can do is make sure they are not in their menstrual or premenstrual phase
at the time of major competition,” she said.
Using the contraceptive pill to reduce premenstrual symptoms, such as fatigue, cramps and muscular pains, can be beneficial during competitions and elite training if symptoms impact athletic performance.
“For women who get significant menstrual cramps and pains, the pill has been used to decrease those symptoms,” Dr Goodman said.
A 2020 meta-analysis in Sports Medicine that found oral contraceptives “might result in slightly inferior exercise performance on average when compared to naturally menstruating women” but stated that “effects tended to be trivial and variable across studies”.
While Dr Goodman says hormonal fluctuations in the menstrual cycle “absolutely can” impact athletic performance, she notes the complexity and variability of the menstrual cycle between individual women, which can show up differently in their athletic performance.
“Performance, fatigue and injury seem to be heightened during pre-menstrual or follicular stage of their cycle, but it’s important to note that all women are impacted differently by their individual cycle,” she says.
High-performance athletes push themselves hard, but some can train so intensely that it can cause them to stop menstruating altogether, a condition called RED-S (relative energy deficiency in sport). Symptoms include periods stopping or becoming irregular, reduced performance, mood changes, and recurrent illnesses and injuries including stress fractures.
Almost 80% of elite and pre-elite female athletes in a 2020 Australian research study demonstrated at least one symptom consistent with RED-S, and almost 40% experienced at least two symptoms.
A combination of physical and mental stressors, such as personal conflicts, relationships, bullying, and busyness outside of training, can add to overtraining.
“Overtraining isn’t only training at a high level but it’s everything else that’s going on in an athlete’s life at the time,” Dr Goodman said.
“This is partly because elite athletes, by nature, are driven and competitive in many areas of their life. They are trying to achieve as much success at a school or university level as they are at a sporting level. They are pushing themselves to achieve all the time.”
WAIS has three in-house psychologists regularly checking in on the mental health of athletes and coaches are advised to reduce training loads if necessary.
“I often see athletes presenting with fatigue, which is not only a decrease in performance but general life fatigue and that is a combination of a lot of factors. That’s when looking into their menstrual tracking and see if their cycle is playing a part,” Dr Goodman says.
Eating disorders
Young female athletes also are vulnerable to eating disorders, with Dr Goodman saying that at least 90% of the eating disorders WAIS sees are in women.
“We see eating disorders presenting much more frequently and at a much younger age than we have ever had before. We’re seeing girls as young as 11 or 12 presenting with disordered eating,” she said.
WAIS has refined its eating disorder policy which now requires coaches to speak to medical staff or a nutritionist if they believe weight is impacting an athlete’s sporting performance rather than approaching the athlete directly about their weight.
“Nobody is allowed to comment to an athlete about their weight nor advise them how to lose weight. We’re trying to educate coaches and all those involved with a female athlete that they can’t be told they need to lose weight,” she said.
“Previously, coaches persuading athletes to lose weight may have contributed to eating disorders, so we’re very focused on preventing and managing eating disorders. It is probably the biggest single issue I see at the moment in female athletes.”
Dr Goodman believes more research will have a positive impact on women athletes’ performances.
“As we do more research into what’s happening during women’s hormonal cycles and in their brains, their mental health as well as physical performance will improve,” she said.
The AIS launched the Female Performance & Health Initiative in late 2019, aiming to improve female athlete performance, health and support systems. In 2022, the AIS conducted a landmark camp in collaboration with the National Women’s Rugby League to study the correlations between sport performance and female health, including the influence of the menstrual cycle and hormonal contraceptives on injury prevention, energy levels, recovery and sleep.
Women athletes all over the world have come forward to talk about period pain being a major cause of discomfort that affects performance. Chloe Dalton, GWS Giants AFLW player and founder of The Female Athlete Project, has reported she suffers nausea and pain every month due to her period. Sprinter Dina Asher-Smith spoke up at the 2022 European Championships about being unable to complete a race due to period pain.
“More people need to actually research it from a sports science perspective,” Asher-Smith told the BBC. “It’s absolutely huge and people don’t always talk about it either. Sometimes you see girls who are so consistent and yet behind the scenes they’ve been really struggling. I feel like if it was a men’s issue, we’d have a million different ways to combat things, but with women there just needs to be more funding.”