The length of a cardio session is common question and really depends on what your fitness goals are. If you want to lose weight then your cardio training will have to be longer than someone maintaining their fitness level. The first point you should note is that there is not much point in doing cardio if your diet isn’t acceptable. If you eat a lot more than you burn up then you will be less likely to lose or sustain any level of fat. Make sure your diet is healthy so you can see results for the time you spend doing cardio.
The best time for a cardio workout is in the morning before breakfast or after a weight session because your glycogen supplies will be very low and your body will get its energy from fat. You should aim to achieve 40 minute cardio sessions, 3 times per week. If you would like to lose fat then you may find increasing to 4, 5 or even 6 times per week may produce better results. If you still find that 6 sessions per week is not enough then you can do a second session 3 times per week but at least 5 hours from the first session. When you’re just beginning a fitness program it is best to ease into it with 20 minute sessions, 3 times per week. It is important to remember not to lose more than 2lb of fat per week otherwise your body will begin to break down large amounts of lean body weight and muscle so that it can supply essential nutrients.
You must always listen to your body when training, so if you are not able to do a full workout then do cardio for half of the time. It is essential to get out there for every session scheduled and you will see results.