My max observed heart rate is periodically going up. Good/bad/neither?
 

Starting cycling last summer. Within a month or two I hit some new observed max hit rates and didn't think much of it.

This spring, when I push myself 100% for some 30 second time window, etc, I'll max my heart rate. Only it seems to be getting higher from month to month.

Last summer a 100% effort landed me at 180. Today I hit some highs when I did some sprinting during our 25 mile daily ride and my max observed is now 187.

Now, I realize that raising your max heart rate has little to do with what we're trying to accomplish in training. Training (to me) is mostly about how much power I can put out at a sustainable pace, how long I can maintain that pace, etc.

But as a side note, is this increasing max heart rate typical? 187 seems rather high and I'm wondering if it'll keep going up! I'm 36. I'm riding frequently enough that I would definitely consider myself to be in good shape (albeit with more pounds to lose).

It is neither good nor bad. And in fact, your maximum HR is probably what it always was, it's just that as you are feeling fitter and getting used to greater efforts you are pushing harder, for longer, than you used to.

People vary enormously in their max HR, and it means virtually nothing. 187 is not unusual at all, especially not for someone fairly young. I am 57 and saw 182 last month, when sprinting for fun with some kids. My max these days is probably in the mid- to high-180s.

What he said. I hit 181-182 earlier this week doing hill repeats. According to the often-quoted but not particularly valid "Max HR = 220-age" formula, I either should be dead (I'm also 57) or my "max" is that of a 38yo. My observed max has been in the low 180s for several years. It isn't something I pay much attention to (other than "boy, that part of the ride was HARD!") unless I'm kidding my wife she's actually married to amuch younger man! :)

Much more useful is the heart rate where you transition from aerobic activity to anaerobic. There are various protocols listed here, in the road racing forum, and in plenty of web sites and books on how to test for and then use that number, and the limitations associated with using heart rate.

Your maxHR varies depending on the activity. Running generally elicits a higher maxHR than cycling. In my case it took a season or two of cycling to reach a similar HR that I had in running. I assume that as your legs adapt to training they can put a greater stress on your heart leading to a higher HR. Ultimately it's your cardiac output that's important and that is a function of stroke volume and heart rate. If your stroke volume increases your maxHR may actually go down with increasing fitness.