There is another frequently asked question, "How hard should I train in order to lose weight?". The definition of exercise intensity is different from person to person. Heart rate is a very objective indicator of how tough should you train.
Here is the suggested heart rate chart.
Photo from NESTA.
Here is the formula for calculating the heart rate:
220-your age= maximum heart rate
For example, the 70% max heart rate of a 30 year old man is:
(220-30) X 70% = 190 X 70% = 133
If you are absolute beginner in exercise, just stick with Light intensity, which is keeping your heart rate around 60-70%. For the general fitness, you can go for moderate intensity 70-80%. Then you can have a standard of how hard should you go for weight loss.
However, you may say that it is fine with the 70-80%, why should I go for high intensity training (heart rate 80-90%)? The high intensity interval training can provide you with an after-burn effect. Your metabolism will be boosted and keep burning calories after your workout.
Of course, you should seek for professional advice before you start the high intensity workout or weight training. If you can't performance basic movement, it doesn't make sense to go for higher reps or loads.
220 - 你的年齡=最大心跳率
例如，30歲男子70％的最大心跳率是： （220-30）×70％= 190×70％= 133
So, I find out the heart rate zone I need to go for. And now, how can I monitor it?
First of all, most of the cardio equipment in the gym has attached with a heart rate monitor at the handles. you can read it during the exercise. However, if you go for functional training or want to have a more accurate reading, then the heart rate watch may be the best for you.
The one I am using is fitbit HR, which I can read time, numbers of steps, heart rate, calories burn...very light and reasonable price. It suits me a lot as I workout almost every day. It tells me when should I meet up with the client and my heart rate during my own training.
Their design is quite fashionable as well. It can be easily matched with your gym outfit or office look.
Here is the link for fitbit: