Johnson operates a hi-tech athletics performance centre near Dallas and has been helping some of Wenger's young players improve their speed.
"It is a fantastic school," said Wenger, who sent defender Ignasi Miquel to the United States this summer hoping Johnson's team of experts might help him be quicker.
"Miquel has a good build but needs to work on his power.
"You have two ways to run quickly. The first is to move as quickly as possible. The second is to have more power on your push.
"If I can gain power every time I push, I can gain five inches or one inch more on each stride then I will be quicker."