Maybe I could get some help fromyou guys here. I havnt ridden for a few months and for the next 2 months my children are living with me. My workouts are going to be limited to the 1up trainer I have and a gym at my apartment complex. I will only be riding my fixed gear bike since I had to relieve myself of my roadbike, long story. So I'm wondering what you would recommend to me. I'm running a 49 ring gear and I have 17 thru 19 cog for the rear. For the past week I've been pushing myself just hard enough to make it through an hour in the morning to build up a base. Any help would be great. Thanks. Should I be swapping between the 16 and 19 cogs every couple of days?