But what to do about this heart rate business? How concerned do you think I should be? It's not as if these were my first two runs ever, in fact they were a little shorter than what I have typically been doing. I have been running relatively consistently for 4-5 miles, 3-4 times weekly for a couple of years. The only difference is that I was primarily a treadmiller and now I am taking it to the streets. Could that have made such a significant difference? I did take a break earlier this year to try a different fitness routine, but even then I still did cardio 3x/week.
I have not used my HR monitor in some time, but I remember that it was always a little wonky, and that the breakdown used by the Garmin software used the "220 - age" calculation.
The "220 - age" is, really, no better than a ballpark estimate. Formulas range from "220 - 1/2 age" to "220 - (age + 10)", and there are probably a couple that include the phase of the moon or the atomic weight of mercury. Some people are "hummingbirds", who hit a pretty high heart rate without much effort, but can stay there. Some people have a lower max heart rate than would be indicated by the formulas, but can stay there for hours.
The best way to really determine your heart rate takes a treadmill, a stopwatch, a nurse or doctor, and a bucket. Basically, you run intervals, faster and faster, at an increasing incline, until you pretty much puke and/or pass out. (Hence, the nurse or doctor - they can also take your pulse during the recovery periods of the intervals.) I'm exaggerating there, but only a little, which is why I do not know exactly what my max HR is. According to my Garmie, and the treadmill, I have a max HR somewhere close to 210, but I don't trust those numbers much.
The better way to run (I think) is using the perceived effort scale.
Level 1: I'm watching TV and eating bon bons
Level 2: I'm comfortable and could maintain this pace all day long
Level 3: I'm still comfortable, but am breathing a bit harder
Level 4: I'm sweating a little, but feel good and can carry on a conversation effortlessly
Level 5: I'm just above comfortable, am sweating more and can still talk easily
Level 6: I can still talk, but am slightly breathless
Level 7: I can still talk, but I don't really want to. I'm sweating like a pig
Level 8: I can grunt in response to your questions and can only keep this pace for a short time period
Level 9: I am probably going to die
Level 10: I am dead
Keep most workouts in the 5-6 range, long slow runs in the 4-5 range, intervals at 4 for the slow, and 8 or 9 for the quick, and you probably going to do okay.
On an obligatory running note - I have been keeping my miles low, since I am supposedly in taper mode for next weekend, but earlier today, I officially finished the "Pedal Across Lower Michigan" challenge, so I will be adding 272 (doubled to 544) biking miles for the month. And yes, someeone did finish before me - she finished up on Friday. But now I can relax, and just run, instead of doing running and biking every day.