How hard is it to run at altitude in Mexico City?
BBC Sport's Sarah Dawkins takes to the streets of Mexico City to find out how difficult running at altitude is.
'You can't catch your breath' - how will Azteca altitude impact England?
BBC Sport's Sarah Dawkins takes to the streets of Mexico City to find out how difficult running at altitude is.
'You can't catch your breath' - how will Azteca altitude impact England?