Originally Posted by
burnthesheep
A seasoned cyclist will have more engine available in the heart and lungs than running legs and injure themselves before they likely achieve anything.
My running threshold HR is about 5bpm slower than my cycling one. Not enough run hours to have the legs built up to use the engine.
LOL, I can ride 100 miles @ 90F with an average HR in the 140-150 range (80-85% theoretical max for my age) but I couldn't run 2 miles if I had to in any temperature at any HR. I might actually complete 2 miles but won't be doing anything for a few days after that including walking.
On that note.. I supplement my exercise with weights and cardio on an elliptical. I can get to any HR I desire on the elliptical and I can get there fast or ramped and and can maintain a rate steady (within reason) or via intervals.