By Helen Neill
Newsbeat health reporter
Andy Murray believes Bikram Yoga has made him mentally stronger
Andy Murray has admitted that yoga gave him the strength to beat world number one Roger Federer at the Barclays Dubai Open.
Not just any yoga though, the 20-year-old tennis star has been practicing Bikram or "hot" yoga.
He said: "It's a little bit ugly. I started in December to try and improve my flexibility in preparation for the Australian Open."
The tennis star admitted that Bikram Yoga has helped him beat players like Roger Federer because it made him mentally stronger.
He added: "It has helped me a lot with my fitness and my mental strength because it's tough being in that kind of heat for that length of time."
Sophie Callis from Bikram Yoga West in London told Newsbeat that it comprises of a series of stretches, performed in a room heated to around 45C.
She said: "In the heat your body is able to go that little bit further because the muscles get so warm."
But she said it is not for the faint hearted and that the 90 minute work-outs are "hardcore".
The heat also helps to prevent injury, aid the healing of existing injuries and it works as a detox because it makes you sweat.
Footballers and martial arts specialists are among those who go to Bikram Yoga West and Sophie said it is because "flexibility is so important in all sport".
Model Elle Mcpherson and Bond star Daniel Craig are also thought to be fans.