Many acts performed by elite athletes are seen as superhuman. Elite athletes perform at a level that is perceived as unattainable by normal standards of performance. These are the result of a mixture of genetics, physical training, and mental conditioning. For example, the highest VO2 max test results ever recorded were from Norwegian cross-country skier, Bjorn Daehlie, who scored a 96 ml/kg/min. The average range for VO2 Max is between 35-40 milliliters of oxygen per kilogram of body weight per minute (ml/kg/min) for men and 27-31 ml/kg/min for women. Another man, Dean Karnazes ran 50 marathons in 50 days in all 50 states in 2006. On February 4, 2015 actor and power lifter Hafthor Bjornsson broke a 1000-year-old record by carrying a 1,433 pound log on his back for 5 steps.