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The 40-yard dash gets most of the attention. But when it comes to evaluating the speed of defensive players, the shuttle run is much more useful. Unlike the 40 which just shows straight-line speed, the shuttle event gives more insight into a player's overall athleticism and burst in short areas.
The drill, which tests an the athlete's lateral quickness and explosion, last a total of 20 yards but has participants spring in three different directions. Players start in a three-point stance and then sprint 5 yards to their right. There they bend down, touch the turf with their right hand. They then sprint 10 yards to their left, touch the ground again (this time with their left hand) and run another five yards.
Coaches view the drill -- which tests lateral quickness, explosion and agility -- as especially useful for evaluating linebackers and defensive backs. Being a defensive player is all about reaction, so the shuttle's emphasis on quick changes in direction become a highly valuable scouting tool. Anything under four seconds is generally considered outstanding; anything close to 4.5 is viewed as a red flag.
The record for the shuttle drills (at least since 2006) is 3.81 seconds, which was recorded by Tennessee defensive back Jason Allen in 2006 and matched by Oregon State's Brandin Cooks in 2014. Allen was drafted by the Dolphins No. 16 overall that spring and played seven seasons in the NFL. Cooks was taken in the first round by the Saints two years ago and had an outstanding sophomore season in 2015 with 1,138 yards and nine touchdown catches.
Defensive back Justin Simmons had the fastest shuttle time last year (3.85) and was also drafted by the Broncos, in the third round.