MLB will be last on that list. All they do is stand around, scratch and spit.
Soccer and tennis are pretty rigorous. So that's what he are hearing first. Surprised not hearing much happening in the NBA.
That is one of the conundrums. It wasn’t seen much in NFL either. Maybe one has to be in constant motion however slight with brief periods of rest. On the other hand these are highly trained and fit athletes...they are working at peak efficiency and could go down for many reasons. But clearly this phenomenon must be investigated. Pat answers very rarely tell the whole story.