Cardio training - how much?

After you pick your cardio training type, the most important thing is how long you do it and trying to keep your heart rate consistent. You should work on this before you work on getting your heart rate high. If you're a beginner, be careful and start with a few minutes, adding a little more time every time you workout until you're up to 30 minutes.
All I hear is to workout for 30 minutes a day on cardio. But, if you don't have that kind of time, do whatever you can. Do mini-workouts throughout the day. Put exercise at the top of your list and find the time, even if you have to do 3 ten minute workouts.
If you feel like you want to exercise more than 30 minutes a day that is fine. But I never do more than 90 minutes of cardio even on a good day. Actually 30 minutes is good enough with my medications to keep my glucose levels in check but keeping your weight in check sometimes takes a little more. You can always start spending some time with strength training if you want more exercise. For more information on cardio training tips, feel free to visit my cardio training page on my website.