This RED-S running workout guide shows how to warm up, train, and recover while protecting energy availability. REDs, or Relative Energy Deficiency in Sport, means impaired physical and psychological functioning caused by prolonged or severe low energy availability, according to the International Olympic Committee in the IOC consensus report. Distance runners face very-high REDs risk because high exercise burn plus unintentional under-fuelling often leads to menstrual dysfunction, bone injuries, lower resting metabolism, and worse aerobic performance, according to the distance-running review. This guide adapts a normal workout around steady fueling, lower volume, and added rest.
Medical information disclaimer: This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a physician or other qualified health professional about symptoms, medications, tests, or treatment decisions.
Table of Contents
- What REDs Changes About Running
- How Do You Warm Up and Pre-Fuel?
- How Do You Run the Main Session?
- What Helps Recovery Afterward?
- When Should You Pause Hard Running?
What REDs Changes About Running
Low energy availability leaves less fuel for health and training. Reported harms include irregular periods, poor bone health and stress fractures, weaker immunity, fatigue, less endurance and power, and slower adaptation. That means performance is not only about fitness.
Missed periods, repeat bone pain, frequent illness, or fading endurance signal an energy gap that training alone cannot fix. First-line care restores energy availability by eating more, spending less on exercise, or both, alongside adequate nutrients and a multidisciplinary team. A run plan should support that goal, not fight it.
How Do You Warm Up and Pre-Fuel?
Eat before you run. Start sessions fueled, not fasted, and bring fluid and carbohydrate for longer efforts. Use a 10-15 minute warm-up: brisk walk, easy jog, leg swings, short strides, and form drills.
Keep the effort conversational and stop if dizziness, bone pain, or unusual heaviness appears. Treat pre-run fuel as part of the warm-up. A familiar snack, water, and planned during-run fuel prevent the session from widening the energy gap.
How Do You Run the Main Session?
Keep most running easy while recovering. Favor short intervals, tempo segments, or steady aerobic miles with full rest, and cut total volume.
In the REFUEL trial, exercising women with missed periods who added about 330 kcal per day for 12 months doubled menstrual recovery and neared 45 kcal per kg fat-free mass per day, according to the REFUEL trial summary. Food is training support here.
- Choose one main goal per session, not speed plus distance
- Use walk or standing recovery between repeats
- Hold back on hills, long runs, and doubles
- Track effort, mood, sleep, and cycle changes across weeks
What Helps Recovery Afterward?
Refuel soon after you finish. Eat a meal with carbohydrate, protein, fat, vitamins, and minerals, then rehydrate and sleep. Schedule real rest.
Include at least one full rest day weekly, add an extra rest day when symptoms persist, and keep weekly mileage lower until health markers improve. Separate easy days from harder days. Light walking, mobility, and consistent bedtime support adaptation better than another hard effort.
When Should You Pause Hard Running?
Pause hard running for sharp or local bone pain, dizziness, missed periods, frequent illness, or falling performance. Seek medical clearance before resuming intensity. Traffic-light tools help guide that call.
Green means continue, yellow or orange means monitor and adjust training, and red usually means stop sport for treatment. Bone needs patience. Increased intake raised weight, body fat, and menstrual frequency without improving bone density versus control in 12 months, suggesting bone needs more time or fuel. Protect the next season by stopping early.