My Heart Rate training questions for the week

I was just reading an article that applies here earlier today.  HR drift over the course of an LSD session of 1-2 hours (at a steady pace) is a sign that your aerobic system isn't sufficiently developed yet.  Sounds like you need to focus on aerobic threshold training.  Read and learn my friend: http://www.active.com/story.cfm?story_id=12685&category=triathlon

I believe the 1 mile test your talking about is to measure progress.  Basically, the goal is to run that 1 mile faster but at the same effort level...more efficiently.  I wouldn't consider a variable HR over the course of a run to be "drift" necessarily.  And I also wouldn't consider 1 mile long enough to draw any conclusions about if you have drift or not.  It takes me a couple miles before my HR even settles in for a workout.  There are lots of things that could impact your HR at any specific point along a run...hills, changes in the surface, wind, even what you happen to be thinking about at the moment.  HR drift refers to the tendency of your HR to gradually increase over the course of a longer session even though your pace is remaining constant.

Hmmm.  Not sure I agree with this Coach Gordo.  Z1 is primarily a recovery zone and used for aerobic compensation.  While alot of LSD work can and should be done in Z1 I can't understand how AeT could be down in Z1.  My understanding is that AeT defines the upper limit of Z2.  At least that's the way my training zones were established from my VO2max testing.

Based in Friel zones and Ken Mierke's work - Aerobic threshold is the intensity at which almost all of the endurance fibers are being used, but none of the speed-endurance or sprint fibers. Basic endurance training is best accomplished at or slightly below aerobic threshold intensity. Basic endurance training forms the backbone of any good triathlon run training program. This training should comprise a higher percentage of most triathletes’ training programs. Most triathletes spend too much time running medium-hard and would do better to slow down for most of their training. Running at a basic endurance pace, in heart rate zone 2, trains the endurance fibers. These fibers have tremendous capacity for endurance, but not much capacity for speed. They do most of the work in any triathlon. Endurance fibers generally produce 65 – 75% of the energy in for an elite athlete in an Olympic-distance race and well over 90% in an ironman distance race. Slower athletes rely even more on the slow twitch muscle fibers. These muscle fibers can withstand and benefit from enormous training volume if intensity is appropriate.

For a rather lenghty exchange on aerobic threshold have a read through this thread: http://www.beginnertriathlete.com/discussion/forums/thread-view.asp?tid=28185&start=1

The article I posted earlier in this thread (by Friel) suggests that in order to fully develop your aerobic system it is important to work the top end of the aerobic zones...top of Z2 if AeT defines your Z2 limit.  That's not to say that you sholdn't be doing LSD in Z1 as well, but be sure to include sessions at AeT...either on their own or combined with your Z1/Z2 LSD work.