Roy Hodgson believes you can read a lot into someone's body language - so Wayne Rooney must be raring to go at Wembley tomorrow.
Despite all the negative publicity Rooney has attracted this summer, and the continued uncertainty over both his Manchester United career and his general fitness, the striker was his normal bubbly self at England training ahead of the friendly with Scotland.
Indeed, so keen was Rooney to get on with it, he was out on the training pitch fully 30 minutes before the remainder of his team-mates.
That action alone seemed to be carried out in order to prove a point and contradicted somewhat David Moyes' claim on Sunday that Rooney is not fully fit.
"Body language is quite an important thing," said Hodgson.
"You can read quite a lot into a player's demeanour.
"You won't have it all the time as they have their own private problems, and at club level in particular you might have one or two who are unhappy with their situations."
Hodgson adopted a strangely light-hearted approach to Rooney's early appearance, raising an eyebrow with his tongue-in-cheek reaction.
"He knows you guys are there, probably," he said.
"He hasn't had enough of the mass media recently and wanted to get his face on TV."
Nevertheless, Hodgson has pledged to take the utmost care with Rooney and intends to analyse his training performance data before deciding on his schedule for the remainder of the get-together.
For the England boss accepts it will serve no-one's purpose, least of all his own, to put Rooney at risk after the hamstring and shoulder problems that have prevented him from making any pre-season appearances.
"Wayne has missed enough football this season and I don't want him to miss anymore," said Hodgson.
"I will have to talk to the medical and fitness people about it because it gets a bit tricky if you decide to start him and see how long he lasts.
"Then you can get past a point where medically he should have been taken off but because he wants to carry on or you still want him on the field because you need a result, you can push him a bit too far.
"I don't want to push him beyond the limit he shouldn't pass.
"I would be very disappointed if he played too long in this game, we sent him back to Manchester United injured and then he missed another period of time."