Arsenal have linked up with US Olympic sprinter Michael Johnson in order to improve their players' physical performance.
The Gunners were visited by Johnson at their London Colney training base as they prepare for their Champions League tie against Olympiakos at the Emirates on Wednesday night.
The four-time Olympic gold medallist runs a running performance school in Texas, which various Arsenal players have attended in order to improve their running technique, and Arsene Wenger believes his players can benefit from the 45-year-old's expertise.
He told The Daily Mirror: "He has no role at the club. He is a runner. We sometimes co-operate with his school.
"For example, if a player needs to work on some aspects of his physical side, we send them there for preparation. It is a fantastic school, but he is not directly involved with our team.
"This summer it has been Ignasi Miquel and a few youth players. Has he come back faster? Not fast enough to win a gold medal!
"But you have two ways to run quickly - I will teach you now. First, is to do as quickly as possible your movement, but you gain that very quickly, you will not improve that at the age of 18.
"The second is that, every time you make your movement, to have more power on your push. That is quite logical. If I can run at the same pace but can gain power every time I push, I gain one inch more. I will be quicker if I can repeat the frequency of my movement.
"He [Miquel] gained some power, but it is always very difficult to measure if you are 18 or 19 - even if you do nothing, you become a man and you look more muscular.
"You get an injection of testosterone between 18 and 21, 22, sometimes up to 23. Then you are a real man. Some get it at 19, some at 20-21."