Originally Posted by
zacster
I can't tell if Lemond is being facetious or not, but Greg hits it on the head. 100w is the difference between riding hard on a flat and taking it easy at a regular, non-sprinting pace. 300-400 is about what you'll put out cranking up a hill, and even spinning up 5% will be 200w+. So where is the exercise they are getting? When I was on the trainer yesterday I was doing 70w on a warm up, basically just spinning my legs. If that's what you put out to engage the throttle you aren't getting much exercise beyond soft pedaling around the park. Yes, they get some exercise, but no more than a spin around the park.
Yeah, I have my doubts about the quality of exercise. Even without any assist I think people don't push a lot of watts, I think untrained people naturally do under 100w, so if unassisted they were doing 180-270kj in an hour (assuming 50-75w, my wife can't even keep up with me when I'm doing 100w on the bike path), then it's even less with an e-bike.
Purely anecdotal, but there's a guy in my neighborhood riding a e-bike and happens to be overweight as well, I don't think I've ever actually seen him pedaling, even on the flat. I have no clue whether he has a physical limitation or not, but if he doesn't, he probably would do a lot better and get in better shape riding under his own strength. I think the thing with e-bikes is that they'll enable a lot of people who are otherwise healthy and capable to get even less of a workout with bikes.