Air is slowly consumed by accelerating. Once the rider's Air Tank is depleted, the rider is forced to run the track on-foot until they arrive at an Air Pit terminal to replenish the Air, which allows the rider to ride on their Extreme Gear again.
In Sonic Free Riders, the player will still remain riding on their Gear, even after running out of Air.
Besides Air Pit terminals, there are many ways riders can earn Air:
The rider can perform Trick Actions when launched from a Kicker/Trick Zone. The amount of Air earned varies on the Rank of the performed trick; the higher the rating, the more Air earned.
Using character skill actions, such as grinding on grind sections, "air riding" (in which the rider flies through the air through dash rings that will give him/her a boost of speed), and the ability to smash through obstacles and barricaded paths without slowing down also fills the Air gauge.
Collecting 30 and 60 Rings will refill and increase the capacity of the Air Gauge.
One of the power-up items that can be obtained from Item Boxes can replenish Air.
Moving the control stick clockwise while riding through Automatic Trail sections.
Actions that use Air include Air Boosting (called "Kick Dashes" in Sonic Free Riders), which burns a lot of Air and should be performed sparingly, and using "Air Slide" to maneuver through sharp turns (Sonic Riders only). If the rider crouches down before performing an Air Trick, this action consumes a slight amount of Air, but enables the rider to access higher route shortcuts when the trick is performed. In Sonic Riders, another action that costs a lot of Air is when the rider executes a Tornado Attack to halt his/her opponents in their tracks.
Different types of Extreme Gears have different Air consumption/accumulation rates. Compared to the average Board type Extreme Gears (which have an average Air consumption rate), Skate type Extreme Gears are more fuel-efficient while Bike type Extreme Gears burn through it twice as fast. Some Extreme Gears' abilities can also affect the consumption/accumulation rate.
One special Extreme Gear, The Crazy, does not use Air but rather uses Rings as a replacement fuel that shares similar properties with Air.