Heart Rate Fluctuations When Starting a Run.

Like you, I have noticed a spike in my HR when I start on a run.  It seems to settle down after the first 1/4 mile or so but really jumps.  When I put the HR monitor on my wife, we have the same results.

I feel some people are sensitive to caffeine in this way. HR way ahead of respirations.

suggest  drop all caffine for two weeks and see what happens. worked just as you need for me, you may see results fast.

Have you verified your HR monitor by manually checking your pulse? It's not uncommon for a HR monitor to read inaccurately in the beginning due to poor contact with your skin. Using some sort of liquid or gel on the contact can help a lot (personally, I use my own saliva but I don't borrow or lend the HR strap...).

Beyond that, are you doing a good, steady warm-up? If not, you may want to do a 5-10 minute warm-up including stretches and a slow increase of cardiac activity. I have a similar issue if I don't warm up (which I don't always do). It's like my body started exercising and forgot to tell my heart. Then my heart tries to catch up. Probably a flood of neurotransmitters to the heart from suddenly starting to exercise. After 5-10 minutes, I'm back to normal.

agree with above.  the HRM tends to go whacky the first 3-5 minutes.  I find that if I'm already warm, or have a light sweat, then it works right off the bat.  I believe the sensor is made to work with a little moisture between your skin and the sensor...since 99% of the time you're going to be sweating.  So sometimes I just splash some water on my chest and under the sensor before starting.  It still jumps around sometimes...but it's much better.

It's quite common for heart rates to spike in the first few minutes.  I know mine does and I know we've had threads here before where quite a few people report the same.  Not an HRM issue because I can feel it happening.  It's part of what easy warm ups are for. 

Put a little water, spit, or EKG gel on the HRM before you start.  I used to have the same issue but a little spit before I go solved that.  Also make sure your strap is tight enough.

Thanks for the replies folks.

I applied a small amount of oral lubricant (spit!) before I ran this morning and the monitor behaved much better.
No large spike at the start nor during the run.

So simple! Thanks again.

+1 on checking your HRM.  Which one do you have?  I noticed this a lot when I ran with my Garmin 301 but I don't see the same thing with my 405.  I think the strap is much better with the 405.