Swiss skier Daniel Albrecht has suffered a serious injury to his left knee in a crash in training for a World Cup downhill race in Lake Louise on Thursday. The Swiss Ski Federation said that Albrecht, who was airlifted by helicopter to a hospital in Calgary, had suffered a \"complex injury\" to his knee but had no head injuries. The 29-year-old has not competed in downhill or Super-G events in nearly four years after spending three weeks in an induced coma to recover from brain and lung injuries after crashing heavily in downhill training in Kitzbuehel, Austria. He returned to competition two years later in December 2010 but the only speed events he has competed in since his accident were a downhill and super-combined in January 2011. The 2007 world champion in super-combined and a four-time World Cup winner, has not been unable to find top form since his Kitzbuehel accident.