I've been riding for ~3-4 years and more seriously for one year.
The maximum my HR would go while riding used to be 172-173.

These last 6 weeks, I've increased my riding frequency and noticed that my max has been going up steadily to 179, over the course of the weeks. My performance has also improved consequently.

Is this increase normal? Any similar experience?

Thanks!

It is not usual for max heart rate to go up. How do you know you were hitting your max previously or even now? Generally it takes a very hard effort to get your heart rate high, followed by backing off for a 30 seconds or so so that you can then put in a maximum effort to reach max heart rate. In my experience, if I don't fell like I'm about to die, I'm not there yet.

Chances are you're getting stronger and the max rate you're experience when riding is going up as a consequence, but that you're not reaching your absolute max.

Something like that would be my guess too.

Also though, max HR as a training tool is pretty much worthless. If you're trying to set zones, use threshold as determined by a 20 minute performance test, much more reliable and useful.

It is possible to increase your max HR with exercise/training.

But I agree it's more likely you have learned to push yourself harder, as above.

Creakyknees, no, nothing to do with training zones.
I often do the same uphill course and at the steepiest parts, my HR always used to go up to a certain limit; now this limit has been exceeded by ~8 BPM! Which I thought was quite significant. I did get stronger during these last 6 weeks though.

Has this been scientifically proven? I'd be interested to know.

Thanks

Max HR while riding is not your max HR.

Keep in mind that your "maximum heart rate" is a prediction based on some factors like your age and the like. It's really not a hard and fast kind of thing. It's really a somewhat dodgy concept; useful, but prone to confuse.

Of course not. This is why I specified "The maximum my HR would go while riding used to be 172-173" and not "my max HR was.."

the highest i ever get to is around 178. But i still feel good, not like im gonna die tired... it just never gets any higher....

Ironically enough, at 187bpm I start to black out. I have hit that a couple times and I start seeing stars and literally feel like dying. 180bpm is my max on a very hard climb with a lot of duress yet not quite enough to cause me unconciousness.

It's been the same for my year of riding.

Your max HR is your max HR. It decreases with age, but usually doesn't increase. What's far more likely is that by being in better shape you have raised your LT heart rate and can stay there longer. If you haven't felt like blacking out, falling off the bike, and/or dying, you probably haven't found your max HR.

Max HR is a physiologic ceiling, a rate that your heart is not physiologically capable of exceeding. It's totally different from the "Max HR" readings from, say, a ride file. That's just the highest HR from that particular ride, not your true physiologic max HR.

It can be a prediction, or for those who dig suffering it can be measured.

For instance, my LT HR while riding is 174. Running, it's 183. Max is 204. I did it once out of curiosity and have no desire to go to 204 ever again.

Wait. Now I'm confused. Shouldn't LT HR be LT HR too regardless of the sport? Max I've ever reached on the road was 195, and I felt like I was going to die but didn't throw up. I did a VO2 max test once and felt like I wad going to suffocate with the mask on, and was afraid I was going to throw up in the mask, but didn't I've just been using 195 as my max and to calculate my zones, until I finally break 200 and throw up all over the place.

No

Nope. Muscle recruitment varies between sports. You can even get different muscle fibers involved when climbing than on flat ground because you've run out of gears and are pedaling at low cadence with high force.

Same thing for me. I seem to "max" at around 170 BPM despite having an estimated 188. At 170 I begin to hyper-ventilate.

At max hear rate, you're well beyond hyperventilating...

RippedUp what's happening is you are becoming more fit. As your ability to produce more energy/power improves your heart and lungs/cardiovascular system is becoming more efficient at uptaking oxygen and circulating blood. In other words not only are your legs becoming stronger enabling you to go faster, longer but your heart is also becoming stronger enabling you to feel better at higher performances. That is what training is all about.

Keep it up!

Enter a race that takes 45 minutes to 1 hour where you really are trying to do your best. Your average HR over that time will be a good estimate of LT. Of course the most objective way to measure it is by blood samples on a stationary bike, but I believe some experts actually define it as average effort at a race pace over that amount of time.

True max HR is difficult to actually measure and will indeed vary among sports. The calculated max numbers are worthless, don't even think of them even as "better than nothing". They aren't.

Once you peg your LT through a good old fashioned 1 hour race pace effort, you can figure out your other zones for various training goals.

By the way, an interesting phenomenon is that as you age, your LT will tend to become a higher and higher percentage of Max. Usually because you can maintain your LT or even increase it, but your max will decrease over time.