When you're in Hunt: Showdown, you need greyhound to get more Lung Fuel.
If you don't have greyhound you will have to stop running to refuel up on your Lung Fuel for a few seconds.
"YO SLASHED, IM OUT OF LUNG FUEL, I need to wait a sec in the bush."
"Okay, I am running out of lung fuel too, watch the Erico."
Having greyhound will enhance your Lung Fuel, without it you will need to take more time to refuel on the lung fuel.
"Yo, cat, I'm out of Lung Fuel.:
"Aight Slashed, I'm almost out too, hide behind the bush but watch out for Erico"