Shorter than that in many cases. Most modern BMX laps are under 1 minute. 30-45 seconds is common depending on the track and rider class. Last weekends national even in Vegas had the fastest time posted by a 15yo kid that was 19.5 seconds or so, with most classes around 30 seconds or less. That is a bit of an exception since it is an indoor track, with outdoor ones pushing that 45 second range more. But it is all a Sprint in the purest sense possible. 
From experience, “endurance” is an entirely new world to most of those riders 