Chief can sprint. Chief can double jump. These both drain the same meter.
For example, you could be battling someone in close quarters and double jump a few times to throw off your enemy’s aim but then you could not sprint away to safety when the fight was over since your meter would be drained from jumping.
Inversely, you could sprint into a battle but then you could not double jump during the fight because your meter would be drained from sprinting.
Sprint would have it’s own button. Double jump would be achieved by tapping the jump button once you were already in the air from your first jump.