High heart rate for run leg

Hi Mary! Welcome to BT.

Whose Zones are you using (each coach/author has slightly different ones) and how did you determine your own heart rate ranges for each zone?

Reason I'm asking, though, is that in most systems Zone 5 is anaerobic ... we're talking short sprints (as in true sprints, not "sprint" triathlons). Your heart simply isn't able to sustain in that level for more than a couple minutes.

I originally calculated my max heart rate based on formula in Sally Edwards' "Triathlons for Women" book, which was the same as the heart rate chart that came with my Garmin. I have the heart rate programmed into the Garmin, which calculates the zones. 

I should clarify that when I said zone 5 it is really on the threshold of 4/5, but still higher than I feel it should be given I am only running an 11 minute mile for a combo workout.

It's a great book. I have an autographed copy from when I met Sally, who is phenomenal.

I can't remember if it says so in the book, but I do know Sally and pretty much any other coach would tell you that a formula MAY work okay for starting out, but once you have a little bit of running and cycling under your belt, it's time to determine what YOUR zones are PERSONALLY.

Check out the first post in this thread, and the links in it for more information.

http://www.beginnertriathlete.com/discussion/forums/thread-view.asp?tid=25733&start=1

You will find, over lots of frequent and consistent running primarily in Zone 2 (with little excursions into 3 and 4 called, say, "hills"), that you can run faster at the same heart rate.

I agree with TriAya.  Make sure you are calculating your zones correctly like in the thread posted.  I would add though that the goal is not to bring your HR down, but rather to be able to run faster at a given HR.  As you increase your fitness, your HR Zones will likely stay the same (perhaps even increase if you are new to running), but the speed you are able to maintain at a given HR will likely increase.  For example, when I started out, I could only run a 10:00/mile pace for my 20 min test and my Avg HR was around 165.  Today, my Avg HR is roughly the same (actually slightly higher) for the same test, but my pace is now around 6:50/mile.

Building running fitness by running more (focus on frequency over distance) will help make you faster.  There is no need to do intervals for running when you are starting out.  It will only increase your chances of injury. 

Personally, I have had better success with using pace vs. HR for training.  I use the VDOT Calculator to help set my pace's for training.  I still wear an HR Strap, but more so to understand how my body responding and measure fatigue. 

I have noted that my run HR is generally higher than the bike HR, in fact, my avg. run HR is about the same as my max bike HR: I did a 70km bike with avg/max 132/161 and a 7,5km run with 165/175, both on routes without steep climbs. This is likely because of the differences in the disciplines, running being a weight bearing sport.

Your max HR is a guesstimate, I've tried different formulas and they all give around the same give or take a few beats, my max should be around 185. Well, I did a bike route with a steep climb, climbing 400m over 8km and hit 235! I thought it was an error but looking at the data the HR was sustained over some time and there were multiple peaks over 200. According to some formulas, with max HR 235 I should be -15years, oh, and last year running in the park I could see my HR peaked as I passed a group of girls, loosing 10 years in a split second!  So, the lesson, don't take HR too literally. HR and zones are a good guidance, but only a guidance.

AFAIK the HR zones are mapped to your metabolism. In different zones the metabolism relies more on some or other processes to produce energy. So, for example 85% fat burning in zone 3, 50% fat/50% sugar in zone 4 etc. Well, in zone 5 you should work so hard that you almost entirely rely on muscular glucose, this cannot be sustained for a prolonged period of time because you run out. 

Hence, if you can sustain "HR Zone 5" for a long period of time, maybe your zones are wrong.

BR

Don't worry about your pace. If you're going anaerobic slow down even if it means walking. When I started using a HRM, I had to slow my run down by 2 min/mile. Now, after 2 months, I'm back where I was pace wise but at a lower HR.

Try to feel when you're starting to go anaerobic, one thing I notice is my breathing rate really picks up. 

When Mark Allen started training this way he had to walk up hills to keep his HR in check. This was just after his 2nd place finish at Kona.