There is debate if it is better to do cardio before or after a meal. The proponents of fasting cardio believe that since muscle glycogen is the lowest in the morning, the body will need to burn fat for energy. Some research shows that indeed people do burn slightly more fat calories when doing fasting cardio. The flip side of this is that people tend to do shorter and less intense cardio sessions when they are fasting due to a lack of energy. This means fewer total calories burned. In addition, those who do fasting cardio may find themselves hungrier throughout the day and eating more total calories than their counterparts who ate before their cardio sessions. Some individuals feel fine doing fasting cardio, but many are plagued with the symptoms of hypoglycemia such as dizzyness. It may be a good idea to carry a small snack (carbs) with you, or eat something very light before starting cardio..
I don't believe there is a right or wrong answer. Do what you feel comfortable doing. The most important thing is to find time during the day for exercise.
If you want to do intense cardio in the AM, make sure you have warmed up your muscles and joints. The body, particularly the spine, is very vulnerable to injury in the early morning. Indviduals with back problems frequently injure the back shortly after wakening. I injured my back many times simply picking clothes off the floor.
Really? NASM and ISSM both say no. Eat breakfast and then do Cardio. Personally speaking (from a trainer's perspective), I would never consider it because the intensity of the cardio exercise will dictate whether or not one reaches a "fat burning zone". 30 minutes is pushing the duration needed. You will have barely burned off the excess glycogen stored from the night before and then your body may digest muscles rather than fat. You run a great risk at burning out if the exercise is too hard (which it needs to be to "burn fat" as you want) and if it isn't hard enough, then it is a waste of time as the caloric burn will be negated by breakfast right after.
On a side note, I got a call at 5:45 AM to sub for a spinning class where the instructor was deathly ill. I grabbed some toast, a glass of OJ and ran out the door for the 6 AM start time. I didn't make it passed 25 minutes in the class. I had to exit the bike multiple times and walk around the studio pretending to correct participants form. It was gross how much energy was I was lacking and how quickly my body just stopped. It is safe to say I didn't burn any fat, just pushed my body to an extreme that isn't healthy.
Bill Phillips claims in Body for Life that doing cardio first thing in the morning burns up to 300 percent more fat opposed to do it at any other time of the day. I am a big fan of the plan but couldn't make the early morning cardio work as I am already at work by 6:15am.
I have been doing my cardio in the afternoon and have gotten more than satisfying results. I guess it doesn't hurt to experiment and see how it works for you. Let us know what you decided and how it goes!
