France are using a cryotherapy chamber at Euro 2012 in a bid to help their injured players recover more quickly.
Cryotherapy chambers expose players to very low temperatures for a short time, a whole-body equivalent of an ice bath claimed to speed the body's recovery.
Midfielders Yann M'Vila, Alou Diarra and Blaise Matuidi are all struggling for the opening game against England.
While France are "not optimistic" on M'Vila's chances of starting, Diarra and Matuidi are making good progress.
Team doctor Fabrice Bryand said: "With the number of matches they played this season, we find ourselves dealing with particularly tired players.
"They spend three minutes in the chamber to help them sleep."
Evidence for the effectiveness of cryotherapy chambers is mixed but they have been used by teams such as Wales' rugby union squad. to apparently positive effect.
Rennes midfielder M'Vila picked up an ankle injury in France's 2-0 win against Serbia last month, and Bryand is not confident on him making France's opening fixture against England.
"His progress is good but we do not want to aggravate the injury," he told L'Equipe.
"We are not optimistic for 11 June. We will increase his workload and see if his ankle swells again or if he suffers any ill effects. We will pay close attention to the player's recovery."
But Diarra and Matuidi, who would both be in contention to replace M'Vila, are recovering well from their knocks.