Would using different training techniques like HIIT be suitable to get a 12-year old into better conditioning for baseball?
Goal: 8% Body Fat, maintain majority of muscle mass
New Years Resolution: stick to a fitness and diet plan that works long term.

I think Hiit would be great. But I think it would be best to define what you think hiit is. Personally kids at that age should be working with bodyweight because they are still growing.
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