5.3 RED-S, Disordered Eating, and Referral

DCO 1.D.3–4: recognize, then refer

The July 2025 outline is explicit. The CPT must recognize the signs and symptoms of relative energy deficiency in sport (RED-S), disordered eating, and eating disorders, then refer the client to—and collaborate with—an appropriate healthcare professional based on the wellness review. Those verbs are the exam. You will see client vignettes that look like “just a dedicated athlete.” The correct next step is almost never “diagnose anorexia and cut another 300 kcal.”

NSCA Coach (November 2025) uses REDs and notes the literature also says RED-S. The DCO prints RED-S. Know both spellings; use the concept, not the hyphen, as the scoring issue.

Low energy availability, not “looking thin”

Energy availability (EA) is dietary energy left for physiologic function after exercise energy is subtracted, often discussed relative to fat-free mass. Low energy availability (LEA) means intake does not cover training plus basic physiology (hormones, bone remodeling, immunity, thermoregulation, growth). LEA can be:

• Intentional (restriction, skipping meals, “making weight,” sport leanness pressure)
• Unintentional (appetite suppression in endurance sport, poor planning, high volume with no extra food, GI issues)

The International Olympic Committee (IOC) defined RED-S / REDs in 2014, with updates in 2018 and 2023, as impaired physiological and/or psychological function from prolonged or severe LEA in female and male athletes. Health effects include—but are not limited to—suppressed resting metabolism, reproductive disruption, bone loss, immune suppression, poorer glycogen synthesis, and cardiovascular / hematologic changes. Performance effects include decreased endurance and training response, increased injury (especially bone stress), slower recovery, and impaired well-being. The 2023 update also highlights sleep disturbance, growth impairment in adolescents, and the role of low carbohydrate availability alongside total energy.

A client does not have to be underweight. Atypical restriction and LEA occur at “normal” BMI. Aesthetic sports (gymnastics, dance, physique), endurance sports (distance running, cycling), and weight-class sports are higher risk—but RED-S is not limited to those sports or to elites. Recreational clients who add two-a-days while “eating clean” (high-fiber, low-calorie) present in personal training all the time.

Female athlete triad: historical related concept

Before RED-S, the female athlete triad described three related conditions in exercising women:

1. Low energy availability (with or without disordered eating)
2. Menstrual dysfunction (oligomenorrhea or amenorrhea, including functional hypothalamic amenorrhea)
3. Low bone mineral density (end of the spectrum: osteoporosis and bone stress injuries)

Any one component was enough to raise concern. Treatment centered on raising EA, usually with nutrition, sometimes with a temporary training cut.

A male athlete triad analog—LEA, reduced sex-hormone production (low testosterone), and low BMD—has been described because men lack a monthly “alarm” comparable to a missed period.

RED-S is broader than the triad. It keeps LEA at the center but expands to multiple systems (endocrine, metabolic, immune, GI, cardiovascular, psychological, growth) and explicitly includes males and para-athletes. Do not say the triad was “fake.” Say it is the older three-component female model; RED-S is the umbrella the NSCA DCO now names. Domain 1.C already allows women’s health / menstrual cycle in a structural evaluation—use that information as a red-flag input, not as gossip, and keep it private.

Disordered eating versus eating disorders (recognition only)

Disordered eating is a subclinical pattern: rigid rules, skipping meals, guilt, compensatory extra exercise, occasional binges, or “I’ll earn food in the gym.” It may or may not meet full diagnostic criteria, and it is still a RED-S risk.

Eating disorders are clinical diagnoses made by qualified clinicians. A CPT learns warning patterns, not DSM checklists to brand the client:

Other specified feeding or eating disorders exist; you do not need to name them. Purging, laxative talk, weighing multiple times per day, hiding food, avoiding team or family meals, and unsupervised extra sessions after already completing your program are operational red flags.

NSCA Coach lists additional observable clues coaches see first: stalled or falling strength despite stimulus, prolonged soreness, recurrent illness, stress fractures, menstrual irregularity, adolescent growth concerns, anxiety around food, and withdrawal from social eating. Males may show low libido, reduced beard/body hair vigor over time, or lab patterns (low testosterone, high cortisol) that only a physician interprets. Mood changes overlap section 5.2—refer rather than picking one label.

Do not diagnose. Wrong labels harm clients and create legal exposure. “I’m concerned about your energy availability and recovery; I want you to see a physician and an RDN who work with athletes” is in-scope language.

Referral and collaboration (1.D.4)

Build the same allied network as 1.B.5, with eating-disorder competence when possible:

• Physician (primary care, sports medicine, gynecology, or endocrinology as the medical team directs) for medical stability, labs, bone health, and return-to-train decisions
• RDN, ideally with sports or eating-disorder experience, for restoring EA—not the CPT’s DIY 2,560-kcal template used as therapy
• Licensed mental health professional (eating-disorder specialist, sports psychologist, or counselor as available) for body image, anxiety, and therapy
• Athletic trainer or other rehab staff when you work in a facility that has them

CPT collaboration after referral:

• Have the conversation privately, without body-shaming or promising secrecy that would block a safety referral
• Stop weight-centric coaching cues (“get leaner for the wedding photos”) while the team evaluates
• Be willing to reduce volume/intensity if the clinician asks; resistance training may still be useful for bone and muscle if cleared, often at moderate loads rather than failure
• Do not add extra conditioning “to burn more”
• Continue session logs and share training-response observations with the client’s consent

Treatment of confirmed RED-S is increase EA (more intake and/or less expenditure) plus psychological care. That plan is clinical. Your value is daily eyes on recovery and a gym culture that does not reward restriction.

Exam traps: RED-S is female-only; triad and RED-S are unrelated; diagnosing from a single missed period; treating extra cardio as the solution; ignoring males with stress fractures and skipped breakfasts; and writing a 1,200 kcal plan as “help.”