From NY times (Hall article):
Scientists debate its effects. The variables that determine performance are complex, said Tim Noakes, an exercise physiologist at the University of Cape Town who served as an altitude expert for FIFA, soccer’s world governing body, at the 2010 World Cup in South Africa.
“If you look at the literature, some people benefit and some get worse, and the general result is no effect,” Noakes said of altitude training. The placebo effect, though, can be significant, Noakes said. He urges those who believe in altitude training to continue and those who are skeptical to skip it. At the elite level of marathon running, he said, psychology probably plays a more crucial role than physiology.
“The more stable you are as a human, the better you are as an athlete, and religion is a very stabilizing force,” Noakes said. “You don’t have doubts. God is looking after you. That’s incredibly powerful. If Ryan finds special strength in his religion, it’s much more important for him than training at altitude.”
I had no idea that some people were discouraging altitude training for runners. Any evidence to support these claims?