Sunday, December 7, 2008

The Non-Fast and The Furious: Cardiac Drift

The long run this morning went well. I was able to maintain the same HR (better actually) that I did during that 4+ mile run on Thursday, with something that I'm very happy about. I was able to go faster (YAY FASTER) than I did on Thursday, an average speed of 12:32 min/mile. That's WAY BETTER than that 14:01 min/mile that I did on Thursday obviously. This also means that I could potentially finish the Pigtails Flat Ass 50k run in 6.5 hours (5.5 hours if I opt to do the marathon distance instead).

I didn't want a repeat of Thursday's wonky HR going all over the place in the first mile, so I walked 1.5 miles to warm-up before the run and it helped greatly. My HR gradually increased instead of going nutzoid. The majority of the group was going to run 10 miles, but since they got away from me - I had to decide which way to go after I lost them. I ended up running over 12.5 miles (12.71 mi according to the foot pod) as a result of this. As I said, this run was better than Thursday. I was able to maintain my HR in the zone I wanted more and could hold my pace longer before I had to walk to bring my HR down. However, after the 10 mile point, my HR was turning seriously unstable. This wasn't the electronic interference that is typical on the Interurban Trail (my HR spiked to 180 bpm!!! Boo interference!!!), but the unstable thing known as Cardiac Drift. Cardiac Drift can happen for a variety of reasons (although sports scientists still say that it's a mystery still). One major thing is when the body's fluid level is depleting and the blood in the body is trying to pump through and since the blood is "thicker", it pumps through harder - jacking up your HR. This is one reason why hydration is so freakin' important. Nutrition on the run is also important as well since that can also cause the same effect as well (you need liquid to help with digestion and if you don't have any liquids to drink, your body will use its own to help).

So after mile 10, every running step I would do moved my HR by 10-20 bpm from the top of my HR zone (jumping from 147 bpm to 157-167 bpm). So I ended up moving very similar to the way I did on Thursday. But I thankfully didn't feel gassed and I caused my drift from what I believe. Why? I didn't bother bringing any water or food with me on this long run. Yeah, I did a rookie mistake that I shouldn't have since I knew better.

But I did good. On zero carried water, I'm able to maintain an easy pace for 10+ miles before the drift effect takes its hold and I can now fend it off a bit more with some hydration on the run the next time.

I think the only thing I could have a genuine gripe about that isn't related to my efforts was that the HRM chest strap actually gave me a chaffing rash and a piece of it was sticking into me that hurt bad and forced me to adjust it quite a bit on the run. It was one of the things (other than my HR spiking so much) that made this run full of cussing (despite how well I did). I think this is why Suunto changed their HRM chest strap design. Others must have had similar problems. It couldn't have been just me. Oh well, looks like I'm going to have to tape up more now for the run to stop chest strap chaffing.

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