This article discusses the use of block starts in Sprint races.
The block start is used in the Sprint races: 55m-400m, and the start of the 4x100m & 4x400m Relays.
The device used (Starting Block) has a center rail with two adjustable foot pedals and is secured to the track by either spikes or pins depending on the type of surface used (synthetic rubber or Grass).
The block start is a crouched position which is the most effective and efficient position that can be used by a Sprinter for accelerating very quickly.
The commands used in a Sprint race are: "On your Marks", "Set", " Gun fires!!!!!!"
"On your Marks"
The Sprinter assumes the position in the starting Blocks in which both hands are close to the starting line but not touching; hand are shoulder width apart with fingers forming a high arch/bridge (thumbs pointing to each other); both feet are firmly pressed on the pedals; only the knee of rear leg (back pedal) touches the ground.
Sprinter raises hips a litte higher than shoulder level with heels pressed backward onto the blocks thus creating tension. The Shoulders and arms counter the pushing force from the legs and helps to avoid a false start.
The knee angle on the front leg (front pedal) must form a 90 degree angle (L -shape); and the Rear leg (back pedal) about 120 degrees and should NOT be fully extended.
"Go" (when the Gun fires)
When the Gun fires the runner reacts to the sound by pushing exposively from both legs. However, the leg on the front block pedal know as the "Power side" should extend fully and forcefully before the leg on the rear block pedal "Quick side" come forward and makes contact the ground.
Block pedal spacing (Toe to Toe measurements)
Bunch or Bullet start: 1 foot length between front & back pedals
Medium start: 1 & a half foot lengths between front & back pedals
Elongated start: 2 - 2 and a half foot lengths between front & back pedals
NB. the measurement from the start line to the front block pedal is usually 2 foot lengths.