If your match is intense, you need to eat some proteins and carbs within the 30 or so minutes following your effort. The best cheap option? Chocolate milk. If not, you can go to a store which specializes in weight lifting and training supplements -- big bottles of powders you can mix with water, milk or else -- and ask them for something you could use after an intense training.
In essence, you need to eat ASAP once you're done and you'll be OK.
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