Relative Energy Deficiency in Sport (RED-S) | Guelph Nutrition

Feb 9th, 2022

Relative Energy Deficiency in Sport (RED-S) | Guelph Nutrition

What is Relative Energy Deficiency in Sport (RED-S)?

As an athlete, you want to perform your best. In order to play your best, you need to make sure you are properly fueling your body. When you are very active, it is imperative that you eat and drink enough (specifically carbohydrates) to provide your body with the energy it needs to perform and recover.  

Energy availability is the amount of dietary energy remaining after exercise, available for other physiological functions such as growth, muscle recovery and homeostasis. 

Low energy availability (LEA) occurs when the calorie intake of an athlete is insufficient to meet the energy required for daily living plus the demands of training. Energy intake should never drop below resting metabolic rate.  

LEA is associated with most consequences of relative energy deficiency in sport (RED-S) and the Female Athlete Triad (the combination of disordered eating, amenorrhea and osteoporosis).  

What are the Consequences of RED-S

Consequences include but are not limited to:  

  • suppressed metabolic rate 
  • menstrual dysfunction 
  • impairments of bone health, immunity, protein synthesis and cardiovascular health 

The consequences can occur in as little as five days and be acute, intermittent or chronic. 

What are the Signs and Symptoms of RED-S?

Signs and Symptoms of RED-S include: 

  1. Reduced training capacity 
  2. Repeated injury or illness (especially bone stress injuries like stress reactions/fractures)  
  3. Delayed or prolonged recovery times 
  4. Change in mood state 
  5. Failure to lose weight 
  6. Reduced or low bone density 
  7. Reduced libido 
  8. Cessation or disruption in menstrual cycle 
  9. Excessive fatigue 

For more information about RED-S and nutrition recommendations to ensure that you are providing your body with enough energy to preform your best, book an appointment with our registered dietitian, Rachel Hannah.   

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Mountjoy et al., 2018 – IOC consensus statement on Relative Energy Deficiency in Sport (RED-S)