Racing flats and running spikes are much lighter than normal running shoes and can contribute to a runner’s speed. They are stripped of cushioning and support to make them as light as possible whilst being able to grip the ground more effectively. But as the name suggests, they are not ideal for general everyday training as they offer less cushioning and support.
Racing flats are good for competitions and as a secondary running shoe on the road, athletics track, or on some trails if the ground is dry, for quality mileage. This would be session based running (short distance repetitions) as opposed to long runs. They are less built up than normal running shoes and are designed to be more responsive under foot so they help to encourage leg speed, so you can run faster.
Track spikes are also made to be very light. Middle Distance and Sprint Spikes will only have the spike plate and a supportive surface but distance spikes have a small heel for shock absorption in longer races. Cross Country Spikes have a more aggressive sole, similar to that of a trail shoe. They come with a set of 9mm spike pins. When the ground gets wetter and boggier its recommended to use 12mm or 15mm spike pins. Sizing for spikes can vary. Spikes and racing flats have a much more narrow last. With racing flats the runner can usually get away with the same size as their running shoes. With spikes however, they are so tight that they actually come up small so you might need to go a size bigger than usual so the toes aren’t squashed.