This is a question that is often sent in to me. I know I have covered it in the past, but I feel that it's worth reiterating and trying to approach the answer from a slightly different angle to help clear up some confusion.
First, Ask Yourself This; How Intensely Will I Be Exercising?
This all depends on the type of indoor cycling that you're planning on doing. Spinning does require special shoes but the good news is that you can purchase reasonably priced options that will last an incredibly long time. If you have purchased a stationary bike and only plan on using it for some casual exercise, you can get away with using regular running sneakers or any type of shoe with a good grip or cleats on it.
Spinning is an intense form of indoor cycling that does require some specialized gear. This is a completely different type of workout that focuses on using your leg muscles. You don't want to give your feet a second thought while working out.
This is why it's so important to get the right shoes as soon as you know that spinning will be your workout of choice for cardiovascular reasons or to build up a solid leg muscles.
Spinning shoes clamp onto the pedal of the bike so that you don't have any worries about your feet slipping. You'll be cranking the flywheel as fast as you can during this exercise program and the last thing you’ll want to have on your mind is the position of your feet. When you’re near the end of the class and you’re really driving it home, all of your attention is going to be on pounding your leg muscles to finish up the class on a high note.
For stationary bikes
If you're going to a gym and planning on using the stationary bike there along with other gym apparatus, you may just want to wear your regular workout sneakers so that you can go from one piece of equipment to another without having to change.
If, on the other hand, you're only interested in using the bike, you might want to look at the various types of cycling shoes available. Take a look at shoes with cleats on them so that your foot will remain stationary while you're riding the bike.
Do You Plan On Working Out At Home?
The same holds true for stationary bikes in a home gym. You'll get better ride performance and as a result will burn off more calories knowing that your feet are secure. It's all a matter of what you are using your in-home bike for. If you just want to hop on it during your favorite TV show and do some casually riding to maintain your fitness or weight level, you probably won't need anything more than the sneakers that you wear to the grocery store.
Sometimes you may experience some problems or other foot issues even if you are only using your bike occasionally. You may find that you can only travel a couple of miles before you start to get uncomfortable. In most cases, proper biking shoes will alleviate this problem.
There are a lot of different types of cycling shoes available (here are some more ideas for you) and whether you need a pair for spinning or for casual riding, they have all been specially designed to make bike riding more comfortable whether you're in motion on the street or remaining stationary in a gym.