
Deep freeze fitness —
Could you survive temperatures colder than Antarctica ... wearing only your underwear ... in the pursuit of fitness?

Three-time major winner Padraig Harrington is not afraid of the cold. The Irish golfer uses cryotherapy treatment as a regular part of his training and fitness regime.

Deep freeze fitness —
Athletes who use cryotherapy must be prepared for a big chill. There are typically two chambers in a cryotherapy unit. The first a milder -60 degrees Celsius (-79 Fahrenheit) and the main chamber chilled to -130 (-200 ?F).

Deep freeze fitness —
Protective clothing to keep the chill away from the delicate parts of the body is a must for these female cryotherapy participants at the pioneering Olympic Sports Center in Spala, near the Polish capital of Warsaw.

Deep freeze fitness —
West Ham United is one of several English Premier League soccer teams to use the mobile cryotherapy unit, which has been on the road since 2013. Here players Andy Carroll, Kevin Nolan and Joey O'Brien prepare to enter its chilly interior.

Deep freeze fitness —
Chilled out New Yorkers can try out KryoLife's "cryosauna" for $90 a session, as the big freeze therapy comes to the high streets.

Deep freeze fitness —
Don't fancy cryotherapy? The ice bucket challenge wouldn't make American swimmer Michael Phelps flinch. The 18-time Olympic gold medalist uses another popular cold remedy, ice baths, as part of his fitness regime.