In 2005, Osbourne started to show more of an interest in fitness through co-hosting the ITV2 show, Celebrity Wrestling:Bring It On!. In February that year, he appeared in Extreme Celebrity Detox in which he took part in t'ai chi and climbing exercises, which possibly inspired him to appear in his own programme, Jack Osbourne: Adrenaline Junkie produced by the same production company (Ginger Productions) as Extreme Celebrity Detox. Osbourne lost (50Lb) 23 kg in Thailand at a Muay Thai martial arts camp in Pattaya in order to be fit enough to climb El Capitan (which he achieved) whilst filming the first series of Jack Osbourne: Adrenaline Junkie. It aired on ITV2 in the UK, the Travel Channel in the United States, The LifeStyle Channel in Australia, GOtv in South Africa and on MuchMusic in Canada. Adrenaline Junkie focuses on Osbourne's training for Sports like rock climbing, mountaineering and a jungle trek in Belize from the Chiquibul Chamber through dense jungle ending at Caracol ruins (guided by the UK extreme conservation organisation Trekforce). He showcased the effects of his weight loss with the two semi-naked photo shoots for Cosmopolitan magazine in 2005 to raise awareness of testicular cancer. The first, taken in June 2005, shows him sitting on a motorbike; the second appeared in the December 2005 issue. After the first series of Adrenaline Junkie he began filling in for Stephen Mulhern on CITV's Saturday morning kids' show Holly & Stephen's Saturday Showdown (the show has now ended). Osbourne took part in Sport Relief and faced former singer in the band S Club 7, Bradley McIntosh, in a boxing match of three one-minute rounds to raise money for the charity. Osbourne won by a unanimous decision.