Energy Availability in a Young Dancer
Priya is 17 and trains as a classical dancer, dancing 18 hours per week across six days. She has recently increased training for a performance and has cut out snacks and desserts because she wants to be leaner. Her weight has dropped 3 kg over two months, and her BMI is now 18.2. She reports feeling cold, has missed two periods in a row after previously regular cycles, and says she is tired but pushes through. Her diet is largely vegetables, salad and small portions of chicken or fish, with no breakfast on most days and no dairy. She is frustrated that she is not improving in technique despite training harder. She has not seen a doctor about her periods.
1. Explain how Priya's current energy intake and training load may be affecting her performance, menstrual function and bone health, using the concept of low energy availability.
Read the worked answer
Low energy availability occurs when energy intake is insufficient to cover the energy cost of exercise plus the body's basic functions, leaving too little energy for physiological processes. Priya's combination of 18 hours of training per week, no breakfast, and removal of snacks and desserts makes this likely.
Performance: With insufficient carbohydrate, muscle glycogen is depleted, so she tires earlier, cannot sustain intensity, and recovers poorly between sessions. This explains why she is training harder but not improving: the limiting factor is fuel and recovery, not effort. Feeling cold suggests a reduced metabolic rate, a common adaptation to energy deficiency.
Menstrual function: The hypothalamic–pituitary–gonadal axis is sensitive to energy status. When energy availability is low, the hypothalamus reduces gonadotropin-releasing hormone signalling, which lowers luteinising hormone and follicle-stimulating hormone, disrupting ovulation. The result is menstrual dysfunction, in her case two missed periods. This is a physiological signal, not a personal failing.
Bone health: Oestrogen supports bone mineral density. Reduced oestrogen from menstrual dysfunction, combined with low energy availability, accelerates bone loss, and this matters especially during adolescence when peak bone mass is being established. The risk of stress fractures rises.
Also relevant: She has no dairy, so calcium intake may be low, compounding bone risk. Her low BMI and rapid weight loss add to the concern. This pattern is consistent with relative energy deficiency in sport, which requires medical assessment, not dieting advice.
2. Outline the advice you would give Priya and identify the boundaries of your role, including when to refer.
Read the worked answer
The first priority is safety and referral. A 17-year-old with rapid weight loss, secondary amenorrhoea, low BMI, feeling cold and a high training load needs medical assessment. Menstrual dysfunction in this context is a red flag, and a GP should assess her, with consideration of bone density and endocrine review. A sports physician or dietitian with experience in relative energy deficiency should be involved. My role is to support nutrition education and eating behaviour within that team, not to diagnose or manage the medical consequences.
Nutrition advice:
- Restore regular eating. Reintroduce breakfast, for example porridge with milk or yoghurt and fruit, to provide carbohydrate before training and reduce the long overnight fast.
- Increase carbohydrate around training. A carbohydrate-containing snack before and after sessions supports glycogen availability and recovery.
- Include protein at each meal to support muscle repair, for example chicken, fish, eggs, legumes or dairy.
- Reintroduce dairy or fortified alternatives to improve calcium and protein intake for bone health.
- Aim for gradual weight restoration, guided by the medical team, rather than continued restriction. Weight gain should not be framed as failure; it is part of restoring function.
- Challenge the belief that leanness improves performance. Explain that her plateau is consistent with underfuelling, and that improved energy intake is likely to improve technique and recovery.
Boundaries: I would not prescribe a calorie target or a specific weight goal, because that requires medical oversight and carries risk in an adolescent with restrictive eating. I would not comment on her body shape. If there are signs of disordered eating, such as fear of weight gain, rigid food rules or secretive eating, I would refer promptly to a clinician experienced in eating disorders. The judgement here is that performance advice must not come before safeguarding.