Energy balance

Female age-group swimmers consuming less than 2000 kcal daily despite high training loads exhibit significant carbohydrate deficiency relative to energy expenditure, leading to an estimated 800 kcal daily energy deficit.

If you are a female swimmer training 6000m daily, your current intake is likely insufficient. You need to increase total calories and specifically carbohydrates to match your expenditure, aiming for at least 7g/kg/day if possible, to avoid energy deficits that impair performance and recovery.