August Krogh

It is no doubt technically possible to study metabolism and respiration of fishes during swimming at a constant rate, and of certain insects and birds during flight, and to obtain information similar to that obtained on man during work on a bicycle ergometer or a treadmill.

I ever will profess myself the greatest friend to those whose actions best correspond with their doctrine; which, I am sorry to say, is too seldom the case amongst those nations who pretend most to civilization.