Relative Energy Deficiency in Sport (RED-S)/ The Female Triad – What every athlete should be aware of
Now that summer is wrapping up and we begin to fall back into our usual routines (see what I did there?), it’s not surprising that many people may be trying a new diet, cleanse, detox, or ramping up the intensity at the gym. As a Sports Dietitian my thoughts on severe dietary restrictions are not positive, but that isn’t the purpose of this blog. With the drastic lifestyle changes many individuals attempt at this time of year, I thought it a perfect time to shed light on a topic that is prevalent in the female athletic community and can lead to serious health consequences.
Relative Energy Deficiency in Sports (RED-S and previously known as the female athlete triad) is a health concern for very active individuals who are driven to excel in sport, however it was previously known to primarily affect female athletes. The triad involves the three following conditions: disordered eating, amenorrhea (irregular or absent menstrual periods), and osteoporosis (low bone density which can increase risk of fracture) (Hertz & Weiss, 2009). Now, RED-S refers to impaired physiological function, which includes, but isn’t limited to reduced/ impaired; metabolic rate, menstrual function, bone health, immunity, protein synthesis and cardiovascular health caused by relative energy deficiency in both men and women (Mountjoy et al. 2014).
If you want to be successful in your training, following a controlled diet is important and can lead to enormous improvements in sport, however you can go too far. Severely restricting your calories will not do any good for your body. Below are some consequences of long-term caloric restriction:
A study that analyzed competitive female long-distance runners found that long-term energy restriction with chronic high-intensity exercise correlated with irregular menstrual cycles, characteristics of disordered eating, and low bone mineral density (Cobb et al, 2003). The American College of Sports Medicine states “energy availability is the cornerstone on which the other two components of the triad rest. Without correction of this key component, full recovery from the female athlete triad is not possible” (Nattiv et all, 2007). Following a balanced, nourishing diet that is rich in complex carbohydrates, lean protein and healthy fats is the way to get you to your peak level of fitness.
Exercising at a high intensity along with restricting calories can cause a decrease in the hormones that help regulate the menstrual cycle. Stafford (2005) explains in her article, Altered Hypothalamic-Pituitary-Ovarian Axis Function in Young Female Athletes, that females who suffer from the female triad have lower levels of estrogen than their peers. Experts believe that a woman stops ovulating and menstruating to guard against pregnancy during extreme physiological stress and in turn conserves her energy to support necessary physiological processes for survival (Stafford, 2005).
Stafford (2005) suggests that long-term energy restriction and extreme exercise disturbs the hypothalamic-pituitary-ovarian axis. Basically this means that a decrease in hormones also affects bone formation and remodeling and encourages the withdrawal of calcium from bone. Despite performing resistance training that is thought to stimulate bone resorption, it can actually increase the risk for developing premature osteoporosis (Stafford, 2005). Even if you don’t experience a fracture now, low estrogen levels during the most important years of bone-building can affect bone density for the rest of your life. Women may further increase their risk with a diet that is low in calcium and vitamin D.
As previously stated RED-S primarily affected women, which was why it was infamously called the female athlete triad until recently. RED-S also affects men, however men are at lower risk but still face many of the already mentioned complications (Mountjoy et al, 2014). It should also be noted that there are specific sports in which there is a higher prevalence for in men, these include: running, cycling, male jockeys, skiiers, gravitational and weight class sports (Mountjoy et al, 2014). Mountjoy (et al, 2014) further report that RED-S can have serious implications for additional body systems with both short and long term effects on health and athletic performance. Athletes with long term low Energy Availability may be at risk at developing nutrient deficiencies, chronic fatigue and reduced immune function (Mountjoy et al, 2014). Physiologically, RED-S can cause medical complications in the cardiovascular, gastrointestinal, endocrine, reproductive, skeletal, renal and central nervous systems, as well as increase the risk for psychological stress and depression (Mountjoy et al, 2014). If that wasn’t enough, carbohydrate deficiency can lead to a reduction in glucose/ blood sugar use, mobilization of fat stores, slowed metabolic rate and a decrease in growth hormone production.
RED-S can affect both men and women. For Women, losing your period is not a convenience — rather, it signals that something is wrong. If you believe you are suffering from RED-S/ the female triad or have been experiencing some of these symptoms, the first thing you can do is to improve your nutrition status by increasing caloric intake and your recovery time in your training schedule. The next step is to seek guidance from your Sports Dietitian and family physician to help prevent the adverse long-term effects of RED-S/ the female athlete triad.
Emilie Trottier, Registered Dietitian
Hurvitz M, Weiss R. The young female athlete. Pediatric Endocrinology Rev. 2009 Dec: 7(2):43-9
Mountjoy, M., Sundgot-Borgen, J., Burke, L., Carter, S., Constantini, N., Lebrun, C., Meyer, N., Sherman, R.,Steffan, K., Budgett, R., Ljungqvist, A. (2014). The IOC consensus statement: Beyond the Female Athlete Triad--Relative Energy Deficiency in Sport (RED-S). British Journal of Sports Medicine, 48, 491-497.
Nattiv A, Loucks AB, Manore MM, et al. American College of Sports Medicine position stand. The Female Athlete Triad. Medicine & Science in Sports Nutrition. Oct 2007;39(10):1867-82.
Cobb, K., Bachrach, L., Greendale, G. et al. Disordered Eating, Menstrual Irregularity, and Bone Mineral Density in Female Runners. American College of Sports Medicine. 2003:711-19.
Stafford, D. Altered Hypothalamic-Pituitary-Ovarian Axis Function in Young Female Athletes. Implications and Recommendations for Management. Treatments in Endocrinology. June 2005; 4(3):147-54.