I am a former runner who still coaches so I tend to think of thing like this in the Track & Field realm. Who in their right mind would go try to run a world record at 1500 (only a 3:30 race) then 5 minutes later try to do a world record in the 5k (only a 12:30 race). Absolutely no one.
Just my opinion but an all out 5 min test… truly done ALL OUT… should wreck you and take hours to recover from. Maybe that’s the point? See what mediocre effort you can give after ripping your legs off?