Originally Posted by
Sullalto
Attack some hills or do some interval work as hard as you can, see if that can make you short of breath.
That sounds about right to me! I can spin along on flat ground with no problems as well. Bicycling is about 5 times more efficient than running... so it can seem easy if your not pushing. But trying to maintain speed on the mile and a half of winding hill I face near daily.... makes me gasp for breath.