A turn of speed
Definition 1 of 1
Pro Tip 1/3Action-Oriented
Use 'a turn of speed' to describe quick, decisive actions, especially in sports or driving. 
The runner took a turn of speed after the last hurdle.
Pro Tip 2/3Unexpected Ability
Implies someone displayed speed unexpectedly, often surprising onlookers or competitors. 
The chess player showed a turn of speed chasing after the bus.
Pro Tip 3/3Short Duration
This phrase suggests the speed increase is brief and not sustained for a long time. 
During the match, he suddenly took a turn of speed to reach the ball.