Tuesday, May 19, 2009

Zone 5 Hazards

I really wanted to go riding again today, but woke up just dead on my feet, so went back to bed and slept in. The weekend was hot and I had a long drive and too much coffee on Sunday, but generally feeling like I have not gotten a good night's sleep since back from Az.

Thinking about that, it seemed improbable. Then I remembered something I'd read in Chris Carmichael's book. He was Lance Armstrong's trainer before, during and now after Lance's terrible cancer. He said when Lance first got back on the bike and tried to train he would have terrible fatigue. By trial and error they found that if he kept his heart rate just at the edge of the anaerobic threshold, but not into it, Lance could ride long rides and recover fairly well.

Thinking back on my own rides over the last couple of months, since I got the heart rate monitor, it occurred to me that even slow, relatively short rides, had sometimes fatigued me if I sprinted up a hill and got my heart rate up over 155 bpm. Before I got my monitor I used to just ride so as not to get blowing too hard, but since, I have made it a point to test my max watts on almost every ride. In particular, I remembered that the ride where my friend Sharel broke her ankle was an especially easy ride, except for the short 3-4 miles riding back up the trail to find her where I got very close to 100% of max HR, and it left me fatigued. This fatigue is also a new problem, so the timing fits with the arrival of HR monitoring.

I think this is a problem for me as I have a right bundle branch block - a timing problem where the 4 parts of the heart don't beat in proper synchronization, and so the blood flow becomes increasingly turbulent as I approach max. Prevalence is 0.7% at 30, 0.8 percent at age 50, and 11.3 percent by age 80. It usually results in about a 10% reduction in pumping efficiency. When I had my "coronary event" in '04, the EMS tech saw the RBBB on the heart trace in about 30 seconds. Anyone trained to read a heart trace will see it instantly.

In addition to a thorough workup when chest pains first appeared in 2000, as a result of my 2004 episode I was given an angiogram where my doctor reported I had no sign of coronary heart disease whatsoever. In fact he smiled and told me I had the heart of a 20 yr old, and he hoped his heart, lungs and aorta looked as good. As welcome as that news was, I still have the impairment, and occasional chest pain.

The rub is that while my calculated max HR is 220-age, or 167, my adjusted max HR is really about 150. When I take my HR up to 163, like on that ride, it's like pushing a normal heart to about 180 bpm. I have reset my HR alert on the Garmin to 155, and will try to keep my exertions below that level to cut my recovery time down to 1 day. I am running out of time to train, and long recoveries are really starting to get in the way. With so many other things coming together nicely, this is now the bottleneck in my training. I hope this does the trick, because June 13th is coming up fast.


Gotta Run said...

I am not sure why I have not wore my heart rate monitor in over a month but after reading your post that baby is going on for my next ride for sure. It shows some great information on both rides and recovery.

Grey Beard said...

Yeah, at first I thought it was some cool biker bling, but now that I am reading some good books I ordered along with it, and learning how to use it, it is becoming an indispensable training tool. Kind of like your gearing, you can either use it or drag it around.

Still smiling at your joyous intro to drafting in a 15-person paceline. For me, that is Zen.

Anonymous said...

You know your heart well! Guess it would be good thing to start monitoring it. Just when I run hills my heart must be up to 190 and I'm not ready to reading it black on white!!!!

Grey Beard said...

You can graph it in any color you like Steph ;-) Yes, it probably is 190, but then you are full of youthful vigor, so no harm done.

When racing in my late teens I did 190+ all the time. Also won a bet doing 1,500lb leg presses - 30 in 60 seconds - and at 124lbs and 27" waist. Big sigh.... oh to be young again... :D ... enjoy your youth, it's a wonderful gift - with a shelf-life.

Nice to have you here Stephanie. Can't wait till you get your Superlight. Was looking at the Heckler...mmmmmmmmmmmmmmmmm!