Look at how fast David Tennant throws himself down those stairs.
This is from the Doctor Who Confidential episode “Stage Fright” (which accompanied The Shakespeare Code)
You can see that the three of them (the Doctor, Martha, and Shakespeare) start together at the top of the stairs. David runs down at breakneck speed - taking the steps at least two at a time - leaving Martha and Shakespeare far behind (Freema and Dean are running more like normal people - being careful to not to kill themselves on the old and probably rather uneven steps).
I don’t think he can even stand up straight on those stairs - he’s crouching down because the ceiling/covering is too low for him. He somehow even manages to make it look graceful. Amazing!