Injuries: If you are carrying an injury, interval training will probably do more damage, you should wait for healing to be complete prior to beginning an interval training session.
Medical conditions: If you suspect you have cardiac disease, pulmonary disease or any other medical condition, please consult with your medical practitioner before starting a program.
Overweight: If you are considerably overweight please see your medical practitioner before starting an interval training program.
Sedentary lifestyle: If you are starting this program from a sedentary lifestyle you need a base level of fitness to participate in interval training. Can you do some sort of exercise for 30 minutes several times a week? For example, ride a bike or go for a run? If not it may be a better plan to build up a base level of fitness before you start an interval workout.If you are severely unfit start with 10 minutes walking a day and build this up. It won’t take long to get to a point where you can comfortably jog at an easy pace for 30 minutes a few times a week.
This may seem frustrating to begin with because you want to start reaping the benefits of interval training as soon as possible, however have a bit of patience, rushing the start can lead to a long time of not being able to do anything. Trust me, I learnt this from experience.
Anything else! Treat your bodies with care, you are about to put them through a large amount by going through an interval routine, please ensure your body is not trying to cope with an additional burden while you go through this.