Run Speed Up

 is an ability in and.

improves movement speed while running and while firing the weapon. It does not affect rolling speed with roller-type weapons, or jump length. Rockenberg gear has a 5× chance of rolling this ability.

This ability is useful when rushing objectives in Ranked Battles during the opening moments of a match. It also increases survivability as the player will be more difficult to hit when strafing in a firefight.

Splatoon
increases movement speed of Inklings in kid form by up to 50%.

Gear
is the main ability of:

Splatoon 2
The effect of Run Speed Up on running while not firing a weapon depends on the weight class of the player's equipped main weapon. It increases run speed by up to 38.5% for players carrying (and not firing) lightweight weapons, up to 50% for those with middleweight weapons, and up to 64% for those with heavyweight weapons. While firing most weapons, the ability increases run speed by up to 25%. While charging or firing a Splatling, the ability increases movement speed by up to 30%.

Gear
is the main ability of:

Stacking
The table below shows how much Run Speed Up increases movement speed while firing, and while moving with the different weapon weight classes.