If you watch, you can see how shorter people have a hard time with many of the obstacles. they say the same thing about the short men who come on the show too. They often mention weight as well. Like someone who is ripped, might have difficulty since jumping and holding onto to 190 lbs. is more difficult than a 150 lb person. No matter what though, it takes a great athlete to finish on the show. I think it is a great show and entertaining to see people run the course.