I've been lifting and doing cardio for about 5 months, the question I have is about my max heart rate. No matter how hard I run and how long, my heart rate can never get above 191 bpm. I'm 23 years old and doing the maxhr calculation, my heart rate should be at max 220-23=197. Should I just asume that my bodys natural max is 191 and should use that to figure my effort levels???

I've been lifting and doing cardio for about 5 months, the question I have is about my max heart rate. No matter how hard I run and how long, my heart rate can never get above 191 bpm. I'm 23 years old and doing the maxhr calculation, my heart rate should be at max 220-23=197. Should I just asume that my bodys natural max is 191 and should use that to figure my effort levels???

Yes. Maximum heart rate is a second-rate guess, a theoretical maximum. Those 5 beats per minute could be quite a level of exertion you may simply not have the experience to be able to summon, or your body may simply not conform to the "statistical average" that created the equations in the first place.

Jeremy

Is it safe to test the waters of one's max heart rate? Is there any danger in maxing it as much as you can for as long as you can? (assuming no medical condition)

Thanks for the reply Jeremy. I think i will adjust my effort levels to the 191 bpm, in the long run it probably wont make that much of a differance :)

Is it safe to test the waters of one's max heart rate? Is there any danger in maxing it as much as you can for as long as you can? (assuming no medical condition)

The golden rule is... if you feel sick/faint ... STOP....

You should be able to max out.. but don't keep it there long.. that's mainly for peaks in HIIT and also cardiac stress testing :)

I also have those problems... On the bike I only get up to 161 no matter how hard I pedal ( 100 - 120 rpm) and I'm only 16. Could it be because of a 54-60bpm resting pulse that's pulling down the max heartbeat?