Relative Energy Deficiency in Sports (RED-S)

By Dr Kaidra Connor – CC’s Staff

Relative Energy Deficiency in Sports

Relative energy deficiency in sports is a term that used to be called Female Athlete Triad. This can be seen in both men and women but is more common in females. It is a condition that occurs when an athlete’s energy intake is insufficient to meet the demands of their training, competition, and overall physiological needs. This imbalance between energy intake (calories consumed) and energy expenditure (calories burned) can negatively impact an athlete’s health and performance.

1. Fueling
   1. An empty tank leads to a leaky faucet. Or otherwise said, if you don’t have any energy to burn, you will likely see the body start to have other symptoms of fatigue. Those who under fuel are 2x more likely to have urinary incontinence (UI), 3x more likely to have UI if one has a disordered eating issue. Pelvic floor physical therapy is a great place to help understand the coordination of your pelvic floor to mitigate symptoms and redirect towards the underlying problem.
   2. Calories > quality. The main goal is increasing caloric intake which can be assisted by your PT in finding an optimal basal metabolic rate (BMR). 
2. Bone density
   1. Estrogen is a key player for bone density where when it is low, it increases bone breakdown and slows rebuilding similar to menopause.
   2. 90% of bone mineral density is accumulated by 18, marking an important fueling window. This increases concern when young athletes are underfueling and increasing their likelihood of stress fractures and setting their future selves up for poor bone health. 
   3. Weight bearing exercises and resistance strengthening with weights is a great place to start working towards increased bone density and weight bearing activities with your PT. 
3. Hormonal imbalance
   1. Hormones are reduced affecting the endocrine system. Men can be seen as having low testosterone and women can have menstrual dysfunction sometimes going with a regular menstrual cycle. When without a regular cycle, this replicates the menopausal and postpartum hormonal environment. 
   2. Lean sports and endurance sports (longer distances) have higher incidences of menstrual disturbances in adolescent and collegiate level athletes – gymnastics, running, cycling.
   3. Physical therapists can recognize the signs of menstrual dysfunction and help encourage proper recovery strategies like sleep, hydration, and nutrition that support optimal performance and hormonal balance.

Overall, low energy availability can play a crucial role in an athlete’s life and needs to be addressed as it has quite a high prevalence but poor recognition and treatment. RED-S can lower bone mineral density, lower cross-sectional area of muscle, decrease strength/muscle mass, and decrease protein synthesis. Consequences can include bone stress injuries, reduced skeletal muscle repair, decreased muscle capacity, reduced maximal strength, reduced reaction time, decreased athlete availability. However, it takes an informed team and can include sports psychologists/ mental health specialists, sports medicine physicians, ObGyns, physical therapists, nutritionists, coaches/exercise specialists, and parents. If this is something that might be on your radar, reach out to your physical therapist for more information and get back to optimal performance!

To learn about how CC’s can help you, check out our team or give our office a call today! Learn more about RED-s by joining us on May 29th, 2025 for our event: Her Health: Health Concepts for Raising Young Women!