I would expect that the type of attention is important. In meditation, when first instructed to focus on their breath, a lot of people alter their breath patter

I would expect that the type of attention is important. In meditation, when first instructed to focus on their breath, a lot of people alter their breath patterns. The practice is getting the attention that rests with the natural breath. Then knowing the quality of that attention, it's possible to see other phenomena without interferance. My guess is these runners didn’t have this attentional skill.