The quick answer is you don’t need to get another set of spikes to run indoors since the surface will be similar to what is used outdoors. The main thing you will need to account for is that there are no weather conditions affecting the track since it is indoors.
So a few things that you should keep in mind is that:
- The surface will always be dry.
- The surface won’t be affected as much by heat changes compared to tracks that are in direct sunlight.
- Wind won’t affect the way that you are running.
You will mainly need to think about the way your foot and spikes strike the ground.
It is worth practicing in your spikes in an indoor track. If you do want to get a separate pair for indoor competitions, you can if it is a preferance.