But the ability to perform repeated sprints for 90 minutes is the one thing a player can’t do without.
More after the break
There are all sorts of training regimes you can follow to help build a tireless engine, but what really works?
You don’t need a gym membership or any equipment, says Mo Gimpel, Southampton’s sports medicine and science manager.
To find out what this essential workout is, hit play and Gimpel will tell all.
Mo Gimpel was speaking at the Science + Football Conference. This year's conference is on Wednesday, April 30 at the London Soccer Dome. For more information visit www.scienceandfootball.com
For more fitness tips see:
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