When doing cardio what is more important calories or your heart rate when loseing weight? alot of people are saying HR but then again alot of poeple say calories.

I only manage to get my heartrate up to 120beats/min.

thats like 65% of the max.

Is it to little ?

I've read that you shd get up to 85%, but to do that, i'd have to run !!

Can't run, not an option coz my kneecaps get painful after a few sessions of running.

Any advice ??

I just got an elliptical trainer and the man in the shop said 65% was the right target for fat burning., well between 65% to 75%.
Because Im not fit its easy for me to get in and stay in that range , he was very fit and said he cant get his to stay up in the higher ranges for long.
I understand its the heart rate to go for as then you can work out for longer without exausting yourself too much too early on and needing to stop before youve done enough to get improvment. did that make sense
I make my excercise easy enough on my legs as otherwise my legs will run out of steam beofre my heart does .

To burn fat, you want your heart rate in the aerobic target zone, which is 65-85% of your max heart rate. It is true that you burn a higher percentage of fat when exercising in the 65-75% range. However, you burn more total calories and therefore more total fat exercising in the 75-85% range. I recommend interval training for burning calories and increasing cardiovascular fitness. Alternate between a moderate pace and a fast pace. Some equipment has an interval training option. You can also do intervals on a treadmill by alternating a flat incline with a steep incline. As far as calories go, I haven't seen much consistency among the various types of equipment as far as how many calories they say I burned. A very easy workout on the elliptical trainer supposedly burns more calories than a strenuous workout on the Gauntlet (down escalator). So I don't trust those readings.

Jen