And my Aerobic Base went from 141 to 156. A 15 beats per minute increase. Remember that I am not an exercise psychologist so forgive me butchering an interpretation of these results. I'm trying to understand what all this means. So what used to feel harder at a heart rate of 155 for example (which would have been Zone 2) now is less of an effort (at Zone 1 now).
A lot of the speedwork Jeremy would assign Tuesdays and Thursdays are the cause of this increase. Pushing up that aerobic base and making those harder efforts a little easier over time. Retraining my heart!
However, in seeing this improvement in heart rate zones, the gain in fat burning efficiency within each zone that I had worked so hard to gain between March and May... is now GONE. Boo. It's all about what you are training. The gains from March to May were lots of miles slightly above aerobic base to just get really really efficient in those heart rate zones with little to no speedwork of any kind.
Note the major drop in Zones 2 and 3 in my ability to burn fat as a percent of total calories burned. Remember that for endurance running, I want to burn fat, not carbs (glycogen). I can run a lot longer eating off the stores of fat in myself than I can from stuffing potatoes and cookies down my gullet.
For those who love more data, fat burning percentage ranges...
Trainer Donnie was happy to see a higher number of calories being burned each minute. Meanwhile, the ultrarunner in me freaked out because to me it means I have to eat more each hour. Especially in later miles when I don't want to eat anything. I guess for future weight loss though and even weight maintenance, the improvement in a good thing... just maybe harder on race day replacing an extra 60 carb-y calories per hours (2 cal/min x 60 min x about 50% carb burn).
Finally, my VO2. Well, that's a tough one. I also can't report an official change in Anaerobic Threshold. We know I went from a 171 to AT LEAST 178. Which is the heart rate this time where I slapped the Stop button on the treadmill before I would throw up in my mask. I'm slightly claustrophic and separately have a strong gag reflex. Put me in a mask hyperventilating while in all-out sprint trying to reach max heart rate and the mask rubs slightly behind and under the chin, and I spent the last minute and a half of each test trying to not upchuck into a closed mask. Eek, I hate that part every time. So we don't have a good VO2 numbers for my higher Zones, but the lower Zones show you I have seen improvement.
But I took the new zones and went back to Tuesdays speedwork. And while it was a hot evening and later miles will show some cardiac drift so that could impact heart rate, it's a good starting point for guesses. It had a good amount of early miles at 12:30 pace, then 200m repeats with recovery at 9:40 pace, and then end up with miles 5-7 being an acceleration run of increasing pace every 1/4 mile until I ended at 10:40. So I put together the following early guesses...
9:40 pace -> Zone 3.0
10:40 pace -> Zone 2.6
11:20 pace -> Zone 2.1
11:50 pace -> Zone 1.8
12:30 pace -> Zone 1.0
I'll try out throughout the weekend these paces and see how the zones fall true.
Yes, I know ideally we would all train and set workouts based on heart rate zone. But most of us don't. We think in terms of speed, so this translation is just easier, just needed.
8 days to Woodstock 50 Miler!