Protein, carbs and colour, every meal. No cutting while you grow.

Every meal: protein, carbohydrate and colour. Within an hour after training: carbs plus protein (skyr with fruit and oats, a cheese sandwich and milk). Calcium daily, a vitamin D plan in winter, water every session. No calorie cutting during growth, and no performance supplements under 18.
S Evidence: strong. Large trials or many studies, pointing the same way.
Desbrow et al. 2014 (professional position statement).
Not medical, legal or financial advice.
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