Diet is something you need to just work out for yourself. Everyone is different. Just don't get fat (like me
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I and another very fast friend have had great success with ultra low carb diets, but on the carbs we both fatten up quickly, so it's a personal thing. We both know another very fast masters sprinter that can't go without carbs. His performance drastically suffers. So there's no hard and fast rules.
If you're carrying fat, lose it. How that is done is a journey you have to take on your own. There's an absolute plethora of diets out there. Choose the one that best fits you and your lifestyle for long term success.