By now you all know I'm obsessed with data, right? If something can be measured and tracked, by god I will measure & track it.
This week, I was scheduled to move up to six GMP miles in a row from five miles, with a two mile warm up and a two mile cool down. My memory of the five GMP miles I did last week was, yeah, it was hard, but not insanely hard, and once I settled into the pace, actually felt good. So I was optimistic going into this run.
I'd also decided that since I'd established that I can run at ~8:00 pace at an acceptable heart rate (ie, under 180) to just start doing these miles by pace, with instantaneous & lap average pace up on my Garmin instead of heart rate. Mainly, this is because when I first started adding in GMP miles a few weeks ago, my goal was, "Just keep it below 180 bpm," but lately that's been resulting in paces in the 7:40-7:50 range. Which, don't get me wrong, is super sweet--that's getting close to my PR half marathon pace, which in the past has required heart rates in the 190s. On the other hand, the whole point of these miles is to practice 8:00 pace, so I don't really want to be running too much faster than that right now. (For all my easy & long runs, I'm still looking only at heart rate & never at pace except for the splits my watch spits out.)
Ten miles total is a convenient distance for me because it means I can do two easy warm-up miles, which gets me mostly out of the start-and-stop world of traffic lights & narrow sidewalks, then run six miles mostly through the eastern half of Golden Gate Park (few lights, wider sidewalks, water fountains), & then finally finish with the same two-mile warm-up stretch in reverse, which spits me out pretty much right back at home. The six miles in the park are mostly gently rolling, with a few shorter, steeper hills, which is a reasonable imitation of what you get at NVM & SRM. Because it's a loop all the ups & downs wash out, and I can be pretty sure that whatever I'm doing in terms of pace & heart rate & all that is a pretty good indicator of what I'd be able to do on that kind of course in general.
I am not even going to lie; this run did not feel great while I was doing it. I was supposed to do it Tuesday but it was pouring rain again, so I switched it with my easy day since Thursday was supposed to be (and was) dry. It didn't feel awful, but I kept getting weird twinges in my shin bones, and I kept thinking I was feeling some grumbling in my right quad/hip/adductor (the problematic one). I never really settled into that nice, "on," crack-like feeling I had on last week's GMP run.
Also, keeping that 8:00 pace just felt a lot harder than I thought I remembered it feeling last week. I kept thinking, "I shouldn't be breathing hard. If I'm breathing hard I should slow down. If I'm working this hard my heart rate's GOT to be above 180. This is like running a 10K." Which, okay, no. It wasn't. Half marathon, more likely. (It's just been so long since I raced a half marathon all-out that I've forgotten how hard that actually feels.)
On the flats & downhills I tried to stay right at 8:00, and by the way having not looked at it for so long, I'd forgotten how instantaneous pace can totally play mind games with you (7:42? 8:18? 7:50? 8:40? 7:30? WHO KNOWS REALLY) & you really have to pay more attention to lap average (or at the very least, process the two together). I kept forcing myself to ease up on the hills, reminding myself that even in a perfectly executed marathon, I should be running those in the 8:15-8:30 range if my goal is to average 8:00 overall. And that was particularly hard, for some reason; both my brain & my body really just wanted to charge right up & get them over with.
I finished the run feeling sort of, "Well, that was whatever it was," but not really thinking it had been all that great. I didn't have any time afterward to download & dissect the data, and in fact it was a full 24 hours before I had time to sit down and actually look at it. Here's what it showed:
I'm very very far from a professional kinesiologist, but I've done my best to educate myself so that when I look back at my own data, I can make sense of the story my body is telling me. Since you don't live in my body & haven't spent years trying to understand the numbers that come out of it, let me interpret as best as I can.
Back when I was training with a heart rate monitor somewhat consistently, I usually did my marathon pace workouts (8:00-8:10ish) in the 175-190 bpm range, depending on how long they were & what else I had done that week & how fit I was & what have you. So to do a GMP workout at 8:05 pace with an average heart rate of 169 is kind of unexpected & awesome--I have never been able to run that fast at that low a heart rate, and while it's obviously a study with one participant and no controls, I'm pretty inclined to chock that up to low heart rate base training.
Obviously I have a long way to go before I can hold this pace for 26 miles, but back in 2011 in my first marathon when my training was patchy at best, I ran with an average of heart rate of 182 for three hours and forty-seven minutes, so getting to the point where I can maintain 169 for (ideally) three & a half hours seems eminently do-able.
As for why these miles felt SOOOO much harder than my heart rate would indicate, I can only guess, but as long as I'm going to guess, I think that a) I was kind of mis-remembering how easy the five GMP miles (at a slightly higher heart rate, BTW) felt last week, and b) I was just tired. It's been a busy week, I haven't slept well, the eight miles Tuesday through absolutely Biblical rain took a lot of out of me, and there's always the added stress of getting ready for the holidays/travel.
Overall, though, I'm encouraged. My sort of secret mini-goal lately has been to run the Foster City Ten Miler on Jan. 18 at 8:00 pace or better, and at this point, barring catastrophe, I actually think it could happen.