Dr Michelle Barrack, associate professor of nutrition and dietetics at California State University, fell in love with running in high school. While she played other sports like football and tennis, there was nothing like lacing up her spikes and racing on the track. And she excelled.

But bone stress injuries and low bone density limited her training and eventually forced Barrack to quit running competitively while at varsity. Her experience sparked a new passion. She wanted to understand the risk factors associated with bone health in runners and help others, especially young women, avoid a similar experience with low bone density and injury.

Barrack isn’t the only scientist whose personal interest inspired their research. Dr Shefali Christopher, associate professor at Tufts University and a former collegiate athlete, was competing in triathlons when she got pregnant with her first child. She wanted to keep training but when she searched for advice on exercising while pregnant, she came up empty-handed.

Barrack and Christopher are part of a growing group of women who are studying female athletes and closing the gender data gap in sports science research. Currently, only 6 percent of sports science studies focus exclusively on women. That means that most training and nutrition guidelines, along with injury prevention protocols, are based on studies of men and how male bodies adapt and perform.

For example, Dr Christa Wille, who studies biomechanics at the University of Wisconsin-Madison, insists on including women in her data sets even though it makes her work more challenging. The female body’s fluctuating hormones can add more “noise” to the data, a main reason why women are excluded from scientific studies. “Why not include women? Why not let them be a part of this? Why not let them benefit from this research as well? We’ve got to start somewhere,” she says.

On an Instagram post, celebrating her successful defence of her Ph.D, Dr Megan Roche, research lead for the Stanford Female Athlete Science and Translational Research (FASTR) Program and ultrarunning coach wrote, “I hope this research plays a small part in building more complete female athletes, with strong physical and mental health. Female athletes and coaches are the future. And I’m so excited to help the research catch up.”

Runner’s World talked to seven women scientists and researchers who are helping to bring better guidance to girls and women in sport. They’re also debunking myths and setting the record straight about the best way women should train.

Bone Health Isn’t Just an Older Person’s Problem
While osteoporosis seems like a concern only for older adults, low bone density is a problem among young runners, as Barrack’s experience shows. Approximately 20 percent of collegiate runners suffer from one or more bone stress injuries per year. What’s more, when Barrack looked at the data on female high school runners, she found that low bone density was prevalent in these athletes too.

Among this younger population, Barrack and her colleagues identified three factors associated with poor bone health. Athletes with fewer menstrual cycles per year or no cycle had lower bone density. Those who ran more than five or more seasons — a sign they may be training year-round — and those who exhibited higher levels of dietary restraint also had lower bone density.

The findings surprised Barrack, suggesting that you don’t have to be a high-level athlete, like collegiate or pro runners, to suffer from low bone density. Barrack worries because adolescence is a critical bone-building period when you accrue the majority of your adult bone mass. Once bone density has decreased, it’s challenging to recover. Among high school runners who had poor bone health, researchers found nearly 90 percent still had low bone density three years later.

Barrack says these trends are showing up in middle school athletes too. “Prevention is just really important to optimize bone health,” she says. “We can’t start young enough.”

For young athletes who are girls, expand your horizons beyond just running and play multiple sports, especially high-impact, multi-directional sports. (Parents should encourage this too.) For instance, studies have found that ball sports improve bone health in young athletes. Strength training can also help. In Barrack’s research, she found that more muscle mass was beneficial to bone.

Fueling Plays an Even Bigger Role in Injury Prevention Than Most People Realise
Researchers have identified inadequate nutrition as the key factor in the persistent problem of low bone density among runners. “We know it’s likely low energy availability that is contributing and affecting hormone function, which will impact bone health,” Barrack says. When athletes are under-fueled, the body prioritises essential systems and suppresses the menstrual cycle and other hormones that are essential for bone health.

But, if athletes improved their nutrition and maintained a positive energy balance, would that reduce the number of bone stress injuries among female runners?

Barrack and Roche were both part of a seven-year study involving collegiate runners  that set out to answer that question. Athletes received nutrition education combined with individual consultations with a sports dietitian. Sessions focused on helping athletes optimise energy intake and supporting athletes identified as high-risk for bone stress injury, based on menstrual health, previous injury and bone health history, and eating behaviour and attitudes.

They found a clear link between nutrition, hormones, and bone health. When athletes ate enough to support their training, they maintained healthy levels of hormones (like estrogen) that are critical for building and maintaining bone. They saw fewer bone stress injuries in female middle- and long-distance runners, specifically in the pelvis, sacrum, and femoral neck. Bone tissue in these areas is more hormone-sensitive and likely to be more resilient because of the healthy hormone levels.

Roche says paying attention to a stress fracture’s location could provide insight into an athlete’s hormonal health. If the injured bone tissue is more hormone-sensitive, it may suggest that the athlete and her healthcare team should take a closer look at hormonal health and nutrition.

While the answer to improving bone health seems simple — eat more — it’s not always easy. Barrack says runners may not meet their calorie requirements because they don’t know how many calories they actually need or they aren’t hungry after exercising, a time when they should refuel. Plus, it’s hard to fit meals and snacks into a busy schedule.

The key is intentional planning. “What’s my next day look like? How can I make sure that I have food available to me throughout the day?” Barrack says. If you don’t have time for a full breakfast, think of grab-and-go options.

The goal is to distribute your calories frequently throughout the day and avoid long periods of time without eating. Aim to eat every two to four hours. And Barrack says don’t skip the carbs. It’s an essential macronutrient for overall health and athletic performance.

Surprising Factors Hold Women Back from Exercise After Childbirth
According to a recent survey, only a third of new moms received any guidance on physical activity. For those looking for sport-specific advice like how to resume running, there’s little to no information.

Dr Izzy  Moore, associate professor in human movement and sports medicine at Cardiff Metropolitan University, wanted to fix that. She, along with her colleagues, set out to understand what factors contribute to postpartum women’s return to running and what hinders it.

In her research, she found that women were hesitant to resume running because they didn’t know “what happened down there.” If they felt heaviness in the vaginal area (a sign of possible pelvic organ prolapse), they didn’t lace up their shoes. The lack of guidelines compounded this uncertainty because it led women to catastrophise every twinge or ache and left them scared to run. Moore says this fear of movement has been identified as a factor related to anterior cruciate ligament (ACL) injuries but hadn’t previously been linked to postpartum runners.

Pain is also a barrier to running and Christopher’s research was one of the first to examine the risk factors that lead to running pain in postpartum women. She found that incontinence, fatigue, lack of sleep (less than an average of 6.8 hours per night), and a previous running injury all increased the odds of experiencing pain.

Returning to running postpartum will depend on personal experience: How much did you used to run? Did you run during pregnancy? Did you experience any pregnancy or childbirth complications? Are you experiencing symptoms of incontinence?

Both Moore and Christopher recommend consulting with a physical therapist first — ideally one who works with postpartum runners or a pelvic floor specialist. Concrete guidance may alleviate some of the fear of movement and uncertainty women may experience.

If something doesn’t feel right in your pelvic region, consult a pelvic floor physical therapist. “A lot of women run and leak urine and think it’s normal, but we confuse common with normal,” Moore says. “Women shouldn’t have to accept that. It can be treated and managed.”

Physical therapists can also identify areas of weakness and develop a strength-building program to support your running. “Your body will be de-conditioned after pregnancy,” Moore says. Start with gentle core and hip-strengthening exercises, like pelvic tilts and hip bridges, before progressing to moves like squats and lunges.

From there, be sensible. “If you used to run a 5K in 20 minutes, don’t do that straightaway,” Moore says. Stick with a plan that gradually builds your run volume like a couch-to-5K program.

While lack of sleep is inevitable for new parents, Christopher says you can adapt your training based on your level of fatigue. You can also reimagine your goals. “If you want to breastfeed and wake up to feed at night, maybe your baseline for running is lower than normal. Maybe you’re running for exercise but not competing because your goals are different right now,” she says.

Women Shouldn’t Be Afraid of High Intensity, Especially During Menopause
There’s no denying that bodies change as we get older and running can feel different. During perimenopause, the phase leading up to the final menstrual period, many women notice an increase in body fat along with hot flashes, fatigue, and brain fog, symptoms that can be debilitating. While changes in body composition can play a role in the change in fitness you feel, research suggests that body fat isn’t entirely to blame.

In a recent study, Sam Moore, a doctoral student at the University of North Carolina Chapel Hill, found that higher body fat percentage was linked to more symptoms in perimenopausal women. But she’s quick to note that the actual percentage isn’t what’s important. Rather it’s maintaining a steady body fat percentage. “Even women who enter [perimenopause] with a higher percent body fat, if their percent body fat was stable across the menopause transition, it was indicative of lower symptoms,” she says.

“Percent body fat is the relationship between fat and muscle. Women are maintaining or increasing fat but more importantly, they’re losing muscle,” says Abbie Smith-Ryan, professor of exercise physiology at the University of North Carolina Chapel Hill, who’s working with Moore. Muscle mass and quality declines because of age and decreasing hormones. “That’s the conversation we should be having,” she adds.

Studies from Smith-Ryan’s lab show that women who engaged in vigorous exercise had fewer menopause symptoms. They believe it’s because high-intensity exercise activates muscle, potentially blunting the loss of muscle and keeping body fat percentage more stable. “It also targets visceral fat, which is likely linked to increased symptoms,” Smith-Ryan says.

While researchers continue to tease apart the cause of menopause symptoms, Smith-Ryan says a great step is to focus on building and maintaining muscle. “Running long distance is good for your mental and cardiovascular health but doing higher-intensity work like intervals stimulates muscle, which is what we see changing the most in perimenopausal women,” she says. Target 75 minutes of vigorous physical activity per week and strength train twice a week.

Your Body Needs New Challenges Beyond Running
Runners can be creatures of habit. We love moving our bodies on the roads and trails. Why wouldn’t we run all the time? Well, there can be too much of a good thing, especially for women in peri- and post-menopause.

“One of the things with runners is our mitochondria are really efficient,” Smith-Ryan says when describing the energy centre in our cells. While efficiency sounds like a good thing, it means that if you run regularly, your body burns less calories than when you were a new runner.

Plus, Smith-Ryan says perimenopausal women show greater signs of metabolic inflexibility, meaning your body has a harder time switching between burning carbohydrates and burning fat, which is key to health. Taken together, this can lead to weight gain and potentially more menopause-related symptoms.

You don’t have to give up running. Instead, Smith-Ryan recommends picking something you’re not good at whether it’s swimming, lifting weights, or doing intervals. Being a beginner will challenge your body — and metabolism — and can help you feel more like you. And while this is true especially for peri- and post-menopausal women, almost everyone will benefit from trying fresh forms of exercise and challenging the body in new ways.

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