Originally Posted by
caloso
It is true that spin classes will give just as much cardiovascular stress as riding for a similar time and intensity on the road. But the question was whether it will help your actual riding, which is a different question. A spin bike won't help your bike handling, your road awareness, your weather awareness, your adaptability to temperature ranges. And as most classes are an hour or less, they don't help with base training, which is the traditional winter riding goal.
That said, I am not anti-spin classes or anti-indoor trainer. I have a trainer just most riders and I've certainly churned out many mindless hours in the garage watching videos and creating puddles of my own sweat. I am just pro-riding on the road whenever reasonably possible.
Don't disagree with outdoor > indoor riding in general, but I disagree with that statement "whether it will help your actual riding."
You should more accurately say, it won't help with your handling outdoors. That's obviously true.
However, given that the limiting factor by FAR for road cyclists and not downhill mtb racers is their power/FTP, working hard in a spin class will ABSOLUTELY help your riding, much more so compared to playing other sports really hard or running really hard, and obviously, if doing nothing. If you keep up your indoor training volume and intensity, be it spin class or trainer, you will be throwing down more power and thus be a faster rider when you're in season again, even if it takes you a week or two to get back in the groove of being on road.
It's a trivial deal to get back to outdoor riding comfort in terms of technique - doesn't take more than 2-3 rides for an experienced rider, even if they take the entire winter off with zero time on a bike.