Research highlights importance of performance nutrition
Neglection of females in study also being tackled
— Mount Royal University | Posted: February 27, 2023
Runners can work with a sports dietitian to develop a personalized plan addressing their unique nutritional requirements, including custom meal plans, hydration strategies and the identification and correction of nutrient deficiencies.
There is no doubt that running has many benefits for overall health and well-being.
Running strengthens the heart and lungs, burns calories and has been shown to reduce stress, improve mood and boost self-esteem. It can also help to relieve symptoms of anxiety and depression.
For some, however, running stresses the gastrointestinal tract, causing symptoms such as abdominal cramps, nausea and diarrhea. These symptoms can affect a runner's performance plus their ability to cover long distances and to race.
Dr. Jill Parnell, PhD, is chair of the Department of Health and Physical Education at Mount Royal University. As an associate professor of physical literacy, Parnell is investigating the connection between running, nutrition and the gut.
Her research has found that individuals with inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) frequently experience gastrointestinal symptoms (GIS) during high-intensity running. The study surveyed 53 runners with IBS/IBD and 37 runners with reflux against a control group of 375 runners with no known health challenges. Commonly reported were stomach pain, cramps, bloating and diarrhea.
It was noted that in pre-exercise meals, runners with IBS/IBD avoided milk products, legumes and meat, while runners with reflux avoided milk, meat and high-fibre foods.
The study suggests that nutrition advice may be helpful for runners so they can avoid foods that aggravate symptoms.
Nutrition is the key
Performance nutrition is a crucial component for runners and active individuals looking to optimize their physical performance and maintain overall health. This involves a strategic approach to nutrient intake, meal timing and supplement use, tailored to an individual's specific needs and goals.
“It’s about optimizing the foods and the timing of meals and snacks to support the body in performing the physical tasks required for exercise to the best of the individual's ability,” Parnell says.
“The second component is ensuring that the dietary intakes help athletes maintain their health under the pressures of training and competing.”
Runners can work with a sports dietitian to develop a personalized plan addressing their unique nutritional requirements, including custom meal plans, hydration strategies and the identification and correction of nutrient deficiencies.
“With the right approach to performance nutrition, athletes can achieve optimal performance and sustain their overall well-being,” Parnell explains.
Dr. Stephen Price, PhD, dean of the Faculty of Health, Community and Education, says that Dr. Parnell's research is helping augment knowledge connecting physical activity and digestion.
“The research will augment our understanding of the impact of diet on gastrointestinal symptoms in runners; notably female runners who have traditionally been excluded from performance nutrition research.”
Research gap between male and female athletes
When it comes to fitness, Parnell says that females are not studied as often as males, meaning half of the athlete population is essentially being ignored.
“The primary argument is that the changes in hormonal cycles would interfere with the clarity of the results,” she says.
“While this is definitely a factor, it can be controlled for by testing at similar times in the cycle and considering birth control and other factors,” Parnell says. “Challenges can be overcome with good study design.”
There is a clear need for diversity in this area of research as female participation in sport is increasing. As an example, the number of female athletes participating in the Olympics has been growing each year, reaching 48 per cent in 2020.
Parnell also argues that females require their own kind of performance nutrition and that iron and energy availability are two key areas that have been extensively studied in female athletes.
“Females lose iron through menstruation and therefore are at a higher risk of sub-optimal iron levels, iron deficiency or anemia. This is particularly important for athletes, as low iron results in fatigue and decreased performance.”
Parnell explains that females also need to maintain a higher level of body fat than males.
“If their body fat declines too much it will affect their menstrual cycle and consequent bone density.”
Price says the focus on female runners is much needed. “This will help practitioners and professionals support high-performance athletics and have benefits for athletes at all ages and levels.”