Cardio Myths

I don't know about you, but I don't like people telling me what I 'have' to do in order to maintain a healthy, lean physique.

'You have to run on the treadmill because that burns the most calories.'

'If you want to lose weight, you must get your heart rate into the zone … that is where you will burn the most fat.'

'You must do cardio first thing in the morning because it burns more fat.'

Have you heard any of these?

It's all a myth and you can toss that type of advice out of the window.

I know plenty of top 'fitness gurus' have been throwing these 'tips' around for years, but I'm not buying any of them. Here's why: there is a huge difference between what looks good on paper or in the lab, and what is practical in the real world.

It is true that running burns more calories per minute than most other forms of exercise. The real question, however, is how much more - does it really matter? If you decide you enjoy riding your bike or jumping rope more, should you ditch these fun activities for something else just because it supposedly burns more calories?

I'm in this for life, so I want an activity that is fun. Who wants to force themselves to do something they don't enjoy? Exercise is hard work, so why not pick something that you look forward to?

Even if running burns 100 calories more per session, that would be a 300 calorie advantage per week when you run three times every week. Considering that it takes 1600 calories just to burn one kilogram of fat, it would take you over a month just to see a one kilogram advantage! So you decide - 1/5th of a pound extra per week doing something you don't enjoy, or forget about the pencil pushers and do what's fun?

Another common tip is to burn fat first thing in the morning. Personally, I enjoy doing cardio on an empty stomach - only because I have trouble running after I eat a meal. I've had clients who felt nauseous trying it but would force themselves anyway because they though it was giving them an advantage I told them to stop!

The science on this is shaky and, like our other example, only provides a slight advantage. If your schedule doesn't permit an early morning workout, or if you find you need something to eat before you can exercise, then ditch this advice and go for it when you are able to. Working out when you can is better than not working out at all. Most people find if they workout when they feel the most energetic, they will burn far more calories than what is promised by taking the 'empty stomach' approach.

What about 'the zone?' This is one of the most prevalent myths around. It looks great on paper. At any given moment, you are burning calories from fat, from carbohydrate (glucose or blood sugar in your bloodstream), from glycogen (stored energy in your muscles) and even from protein (yes, protein is also a fuel source). When you are 'in the zone' you burn a higher percentage of calories from fat - this is true!

The fat burning zone is actually a slower zone: you are burning fewer calories per minute. Hypothetically speaking, you might burn 60% calories from fat in this 'zone' as opposed to just 40% calories from fat if you train more intensely. So?

If you burn 400 calories pushing hard, 40% of those will come from fat, or 160 calories from fat. If you purposefully do an easier workout and slow yourself down because you want to be 'in the zone' you may only burn 250 calories in the same amount of time. Sure, you are burning more calories from fat, but 60% of 250 calories is 150 calories. That's fewer calories from fat, because you gave less effort.

Do what suits your schedule. As head of technology for a rapidly growing wireless company, I don't have much time to waste on workouts. Therefore, I do a quick, high intensity, 20 minute workout a few days out of the week.

I forget about the zone and just go 'all out' and burn as many calories as I can in that short period of time. I love to jog, so when I do have the chance, I go on longer, slower runs - focusing more on where I'm going and the scenery than what my heart rate is.

The bottom line is that cardio is best when you do what you like, when you can, the best way you can. Now stop reading and go sweat!