Originally Posted by kuan

May I ask why you only have three hours? That seems like a lot of stress to me, trying to get three hours in a week. The rest of your week must be hellish!

You're 40, I'm 38. I can't do more than one seriously hard workout a week. I can't do more than 30 minutes at any kind of intensity above my LT. It takes me 2+ days to recover. Both of these days can't be anything more real easy riding or running, around 136-140 HR. I workout about 6 times a week though. The harder workouts consist of one distance workout of 1.5-3 hours starting at around 70% and ending at 80%, and one interval workout. I'm just starting out on intervals right now, so the total work at the moment is around 10 minutes. I started with a HRM last year with a RHR of 59. My RHR is now 46, my MHR is 183. Let that be your kinda-sorta guide. What to do what do do?

Edit: I don't want this to be about me. I can only give advice based on experience and can't really quote any studies and stuff. To date I haven't done much interval training. Start with one session every 10 days and work up. Keep the hard work minutes low. You don't need to do that much. I think the cardio adapts real quick.