Collegiate Runner with Amenorrhea and a Stress Fracture
A 19-year-old female cross-country runner is 1.70 m and 51 kg and competes at the collegiate level. She has run 65–75 miles per week for eight months and has had no menstrual period in seven months; she says her doctor told her this is 'normal for runners.' She sustained a tibial stress fracture last season and is currently in a walking boot. She describes her eating as 'clean' - no dairy, no added fats, rarely red meat - and reports constant fatigue, feeling cold all the time, and insomnia. She has sought you out to lose 'a couple of pounds' so she can run faster, and she asks whether she should fast on rest days.
1. What is the most likely underlying problem, and which findings support it? What do you make of the physician's comment?
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This presentation fits low energy availability / RED-S until proven otherwise. The supporting findings cluster: seven months of amenorrhea, a tibial stress fracture, a BMI around 17.6 (51 kg at 1.70 m), a restrictive 'clean' intake pattern with no dairy or added fats, plus fatigue, cold intolerance, and insomnia on 65–75 miles per week. Menstrual dysfunction, a bone-stress injury, and inadequate fueling together form the classic pattern, and the fatigue and cold intolerance suggest broader systemic effects rather than a single deficiency.
The physician's comment matters but should not be attacked. Amenorrhea in a high-volume runner is common, which is not the same as normal - it signals that energy availability is too low for her body and carries bone and hormonal consequences. The remark may also have been taken out of context. Suggest a second opinion and a sports-medicine and sports-dietitian referral rather than telling her the doctor was wrong.
Your role is to recognize, document, and refer. You do not diagnose RED-S or prescribe treatment for it.
2. She asks to lose 'a couple of pounds' and wants to fast on rest days. How do you respond, and what language do you use?
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Decline the weight-loss goal, and lead with performance rather than a lecture. For her, further restriction is likely to deepen the exact problem that is already costing her races: stress fractures, missed training blocks, and fatigue. Language: 'Losing weight right now would work against what you actually want - being healthy enough to train and race. Fasting on rest days is the opposite of what your body needs to repair bone and recover.'
What you can offer: help her fuel consistently around training, add energy density and variety back into meals, protect sleep, and coordinate with her care team. What you should not do: set a calorie target, set a goal weight, or prescribe a meal plan to treat amenorrhea or bone health. Those belong to the physician and registered dietitian.
Watch for red flags - secrecy, rigid food rules, body-checking, distress when the topic of weight comes up, or deterioration after your conversation. If they appear, refer promptly to a clinician experienced in disordered eating. Validation first, redirection second.
3. If she is medically cleared and stays with you, what would a safe coaching plan look like, and how would you monitor progress without focusing on weight?
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Work inside a team. Confirm who is managing the bone injury and her menstrual and hormonal health, obtain a release to communicate, and follow their guidance on training volume and any nutrition targets. If that team is not in place, establishing it is the first step - not the coaching plan.
Behaviors to coach, not numbers:
- Eating before and after runs, including carbohydrate before morning sessions.
- Adding energy density and variety back in: fats, dairy or fortified alternatives, iron-rich foods paired with a vitamin C source.
- Sleep and rest-day routines that support bone healing.
- A flexible relationship with food, dismantling 'clean' rules.
Monitoring: training tolerance, energy, sleep quality, mood, and bone-healing milestones, plus menstrual status as reported by her physician. Do not use daily weighing or body-composition testing as progress measures. Review every two to four weeks and confirm her care team remains engaged. If her symptoms worsen or she becomes more restrictive, refer again and step back from nutrition coaching.