Set as a feature request. Good idea as well!

Thank you, Deadfast. Cheers! :-)

every tried sprinting as fast as you can for 400 meters and then go prone? it kills you.
disagree on going prone.

you cannot "sprint" long distances. either you jog, run or walk.

Doesn't really work irl either...

Going prone wouldn't help too much, you're flat on your chest compressing the air out of it, also leopard crawling on the ground is very tiring so you would gain fatigue from that... I think it's fine at the moment considering how much equipment you might be carrying.

After running long distances your better off walking for a good while than your are stopping/sitting/laying. You want your body to get rid of the lactic acid in your muscles and walking helps the oxygen get back into your muscles better than stopping/sitting/laying, and lack of oxygen and fuel is what causes fatigue in the first place, so I can't agree with this.

Arma 3 already has this (a prone player recovers in less than half it takes a standing player, while a sitting player takes just over half)

See the fatigue tables I did a couple of weeks ago:
http://forums.bistudio.com/showthread.php?154557-Not-liking-the-new-Fatigue-system-Jogging-should-not-be-penalised&p=2391960#post2391960

However, as others have mentioned, this isn't really very realistic.

People on the forums are fighting for slowing down the stamina reduction when prone.Its silly to run forever and then just drop to prone and your sway rapidly returns to normal and you guys are asking for a quicker reduction?Are you guys understanding what is being asked for here?

It does now with the new stamina system. This is solved.

@Astaroth I've checked - it's resolved. Ticket can be closed.