Devy Speed Kills: Predicting Future Freaks - Dynasty Nerds
What is the average 40 yard dash time for any adult human? - Quora
Is 4.8 a good 40-yard dash time for a 41-year-old man? - Quora
Baylor's Tyquan Thornton receives official 4.28 40-yard dash time
Trace McSorley has top 40-yard dash time among quarterbacks
NFL combine: Tyquan Thornton records near historical 40-yard dash time
Tyquan Thornton sets new record 40 time at NFL Combine
An NFL prospect can win his own island if he breaks the 40-yard
How Are 40-Yard Dash Times Recorded?
NFL combine's 13 fastest 40-yard dash times on record