Once the brain starts cooking, you can act almost immediately and it still might not save the kid.
Lejeune Marine’s PT death leads to new safety measures
Had the Marine in ice within 5 min of collapsing, did no good. 99% of the time when a kid gets loopy on the practice field because of heat, it's due to heat exhaustion not heat stroke, and the treatment is shade, cool wet towels, remove shoulder pads and other items that retain heat, and hydration. Could be other factors that played a big role in the kid dying other than not putting him in ice bath fast enough.