all depents on the instructor.
If he's a cyclist, you have classes who can compare to "real cycling". I hear from some of my colleagues that there are a lot of "aerobic" people in indoor cycling, both in US and Europe.
Which is pitty and not at all what the "inventors" of indoor cycling had in mind.
But it can't hurt to try out, does it?
Maybe you can check for the education the instructor had. Nautilus (Schwinn) and Spinning have good instructors.
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