EA Sports' Player Performance Index shows both players have recorded a speed of 22 miles per hour over five seconds, with Vardy setting the pace back in August in Leicester's 2-1 win at West Ham.
Vardy's rapid sprint was matched by France international Martial in Manchester United's 3-3 draw against Newcastle at St James' Park last week.
"The identity of United's fastest player has been debated among the first-team squad for the last 12 months with Chris Smalling, Antonio Valencia, Luke Shaw, Ashley Young and Wayne Rooney all among the leading contender," Manchester United said on their official website.
"Yet that debate was eventually put to rest when the captain was clocked at 35 kilometres per hour during the 3-1 win over Aston Villa in April 2015.
"Interestingly, Rooney's figure from last campaign equates to 21.74mph and that is, of course, just slightly slower than Martial's top speed registered against the Magpies."
Vardy's Foxes team-mate Jeffrey Schlupp has proved he is no slouch with a top speed of 21.9mph, with Tottenham right-back Kyle Walker, Liverpool striker Divock Origi and Newcastle defender Paul Dummett peaking at 21.8mph.