What should your heart rate go up to during cardio?

There is a Formula call CARvonen basicly calculate ( 220-age ) - resting hr x Intensity ( 50%) + resting hr = it will give your cardio hr ( intensity would be diffrent for individual )
Before you do any training you must check your health and work out specially for your target
for example ,5k,10 k,marathon or only for weight loss
not only hr important ,time ,repitation and will make training intensity
I hope that help
Murat Gecmen
Bsc( Hons) Sports science
Personal Trainer

From a safety perspective I would broadly agree with what Barry has said. I would add though in my 20 years experience I have noticed that with most people you can add another 15 % of heart beats to achieve a more accurate appraisal. In addition if you ask them how hard they are working on a 1 to 10 scale of perceived rate of exertion , 1 being very light 10 being flat out, the Heart rate percentages and this perceived rate of exertion should broadly match. For Example if I was 40 years of age on the 220-age scale my maximum heart rate would be 180bpm, if I was to work at 70% of maximum this would give me a training heart rate of 126bpm. I have found that if you ask that same person how hard they are working at that level they will say something like 5 or 6 out of 10, never 7 which would match 70% of maximum heart rate. So the rules are; play safe but you may find that you can add another 15% worth of training intensity and this will be more realistic. If in doubt stick to the 220-age scales until you have the opportunity to work with an experienced professional.

Hi there Judy J ! I believe the question has been answered by Barry Deeks . Finding your max Heart Rate is deduced by taking your age off the figure 220 , this gives you a rough estimate of your Heart Rate Maximum . The fat burning threshold is 60% of you HR max , the longer you stay within that zone the more calories you will burn , an average workout of 30 - 60 mins could burn approx 250 -600 calories depending on fitness level etc . Interval training will increase your cardiovascular strength and endurance , of which you train at different percentages of the HR max i.e interval sprints of 70 % max for 1 min , rest , then repeat x 3 . The healthy limit is dictated by your individual stamina , fitness level and willpower . Have fun !! J

It depends on what kind of cardio training you are doing, but your main Heart Rate zone is 55%-90% of your Max HR.
Max HR is 220 take away your age which equals 100%. E.g. if you were 20yrs old, your Max HR is 220-20= 200beats per min. So 90% of that will be 180bpm.
DKS Fitness