A woman experiences irregular menstrual cycles after starting intense endurance training. Which mechanism explains this phenomenon in terms of hormonal balance?

💡 Explanation

Intense endurance training can lead to a negative energy balance. Because the hypothalamus is sensitive to energy availability, energy deficit suppresses gonadotropin-releasing hormone (GnRH) pulsatility, therefore reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, rather than directly affecting estrogen, cortisol, or leptin sensitivity.

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