Originally Posted by MrJames67

200 bpm? 15 minutes? To me that is amazing. Like Dean Karnazes in a way. He has a body that scientists have found does not have lactate buildup; it clears before it can build up. So he can run hundreds of miles without stopping.

I'm going to try your suggestion about different positions on different bikes on my training road here, all uphill. At 77 and not well-trained, I'm not out of breath or breathing that hard, just bad muscle burn after about a hundred feet up the hill. Working on it twice a day usually for 30 minutes and low gears, high gears, sitting or standing, high or low cadence. I break down at the same point at the top of hill. It's frustrating although I can do it in higher gears than a month ago. I do figure eights at the top, on the level for recovery, and zoom back down after two minutes by the clock, and do it again. And again. I just started working on shortening that recovery time. Calorie intake seems to make little difference in these results and my nutritional and biannual blood draw readouts are perfect. I just don't build up endurance easily. But I will try it on my other bikes andI am persistent.