Training & Nutrition - Maximum Heart Rate...Temperature!?

I cycled yesterday here in Petaluma where the temperature was around 110 degrees outside on the road. At some point I reached maximum heart rate, 99%, under the 110 degree sun after a hour and a half of bike riding well hydrated.

I felt very strong going uphill and hitting maximum HR did not felt that painful, my legs felt fresh and I could keep pushing with much more power. Although I do not feel I am going to collapse, Could I have a heart attack, seizure or whatever if I stay too much at MHR even if I do not feel too much pain or strain?

Heat will raise your HR, your body has to dilate the vessels to keep you cool which means your heart has to work harder. I generally run +5% for the same effort in the summer vs the winter. Chances are you just never really hit your MHR and the heat helped you establish a new one. If it concerns you or if you are having chest pains go see your doctor.

I am in my 30s right now, have done a lot of surfing when I was younger, for a while got hooked with running 8 to 15 miles every sunday, and for the last year I started cycling. I follow a very good healthy diet by watching out my sodium, sugar, fat intake, non-smoker, I dont drink any alcohol and cycle almost every other day at least 30 miles.

Thank you for the quick reply, at the present time I do not experience any chest pain at all. The thing is although I have done a lot of sports and follow a good diet, I am not used to see my heart beats way in the level 5 zone; so is it ok to have the heart beat 180-185 as long as I feel good and strong. I am not trying to sound humble or stupid, but its the truth, I was hammering it up this hill with plenty of energy and power and when I looked at the watch computer I got scared that it was reading 98-99%. I honestly dont know if something could happen to me although it felt amazing climbing that hill yesterday.

Well if your feeling good, you probably have not reached your max. When you hit your max you should be ready to explode, black spots before your eyes and feeling like your lungs have stopped working. I'm 51 and my MHR=197 so you can't go by the calculations, you just have to go out and hit it. You may not be at 98%-99% but more like 90%-95%. Also if you have done other sports such as running your MHR for cycling will probably be higher. My MHR for running is 10% lower than for cycling.

I felt very strong going uphill and hitting maximum HR did not felt that painful, my legs felt fresh and I could keep pushing with much more power.

That's not your MHR then. How did you obtain it? If you used a formula with "age" as a variable, you can throw that number out the window. Find your realy MHR, and go from there.

... Brad

Ok, I get it now in regards my new max rate, if I reach that max point like you say of seeing black spots and can almost talk to the gods of pain; as long as I do not feel any chest pain; Is it dangerous? Could I suffer any kind of seizure or something like that?

I just get a little bit, well scared (lol), when I start feeling my heart beating so strong as never before.


That is very good, 197! Amazing!

I think the most I have reached its been like 188-190, but still have some fuel on the tank. I can keep going but dont dare to go any higher.

True, 220-age is a conservative estimate value.

If you want your real MaxHR, you'll need to go through a stress test.


That's not your MHR then. How did you obtain it? If you used a formula with "age" as a variable, you can throw that number out the window. Find your realy MHR, and go from there.

... Brad