On the Go is a Handling perk introduced in Call of Duty: Ghosts. It allows the player to reload while sprinting. However, it disables the ability to reload cancel by sprinting. It is a passive perk in Extinction mode. It is referred to as "Sprint Reload" in Safeguard.
On the Go is generally not favored by many players due to it disabling reload cancel by sprinting. Most players stick to Sleight of Hand, as it speeds up reloads without interfering with reload canceling. On the Go still has its advantages; it costs one less perk slot than Sleight of Hand and allows the player to stay mobile at all times. This can prove especially helpful in Blitz, as the player can reload their weapon on the way to capturing the objective without having to slow down. On the Go can also help in situations where the player is taking fire but hasn't topped off his weapon yet, as the perk allows the player to reload while sprinting for cover, making it easier to return fire quickly.
While the other one point perks are mostly bonus additions (such Resilience or Gambler), On the Go is a bit more specialized. It is not recommended to just throw it into the player's class, as the difficulty to reload cancel may hamper their playing style. It is best to use it in a class where the player knows they will need it.