Animated GIF playback speed


Problem: recently, I started creating animated GIFs using ImageReady 7.0. But when I upload it to my website the playback speed is very high. I had been thinking on having the same image on consecutive frames, but I thought that may increase the file size of the image and it will take more time to load.

Question: how can I lower the playback speed of the animated GIFs without increasing the filesize much?