I'm new here. I am racing my first duathlon in August. I am using Gale Bernhardt's training plan. So, I figured out my lactate threshold heart rate on the bike. Then I added 5 beats for my run part. I haven't ever really used a h.r. monitor for training. I went out for a run this morning and was suppose to keep it no higher than 148 but it kept going higher than that. I had to keep walking to get it to come down. Now, a little about me. I'm 50, last year was way over 200 lbs, have dropped 45, still working on 20 more. I've spent the last 5 months working with a fitness trainer who helped take my endurance and stamina through the roof! this past saturday I went for a 41 mile, rolling hill ride with a local group. I haven't been on my bike more than 3 times this year and haven't ridden that long in 15 years. and today 3 days after the ride, I've had no soreness or any signs that I did that long of a ride. My trainers drills worked! anyway, I'm just unsure about the heart rate thing. does it just take time? I couldn't run any slower, I had to walk to get it below 148. Any ideas? thanks.