Losing weight is a simple process and basically comes down to creating an energy deficit — that is, burning more calories than you eat – apply this formula consistently, and the scale will  tell you that you’re getting lighter. 

But is weight loss the same as fat loss? Not really. How you create that all important energy deficit will determine if you lose weight in the form of fat, muscle and fluid or mainly fat (which is the desired outcome) – but more about that later.

So what is the role of exercise and more precisely cardio workouts for fat loss?

Many of us believe the path to that energy deficit is more exercise: making energy out higher than energy in. More hours running in the park. More hours on the exercise bike at the gym. More hours in the pool.

Conventional wisdom dictates that, if you want to shed fat, a punishing exercise regimen is the way to do it — but conventional wisdom is wrong.

While it’s true that exercise does burn calories – it burns a lot less than we think.

mailchimp image lifestyle exerciseThere’s a common misconception that you burn the most calories doing high-intensity cardio workouts, but in a given 24 hour period you actually burn more calories  going about your daily activities, house duties, shopping, sitting at a desk, resting & sleeping etc. The calories that you burn at rest are known as the Basal Metabolic Rate or BMR a term which describes the energy your body uses to fuel its basic functions.

Your BMR accounts for a surprisingly large portion of your total energy expenditure approximately 60 to 70 percent.

Of the energy you take in from your food, physical activity uses up the minority of it. That’s true even if you’re a professional athlete or have a very labour-intensive job.

But what about all that effort in your recent gym session or power walk?

You may think you have burned through many hundreds of calories running on the treadmill or doing a high intensity cardio session but in actuality you haven’t – most people underestimate how much exercise they have to do to burn off fat or compensate for the calorie laden meal earlier in the day.

According to Harvard calculations, a 70kg person (about the weight of the average Aussie woman) who runs at 10km/h for 30 minutes will burn 372 calories. Many people will struggle to sustain that level of effort, let alone keep up it up every day.

But you could achieve the same energy deficit just by cutting out  daily snacks — a can of soft drink (160 calories) and two chocolate biscuits in the cup cakesevening (200 calories), for example — or by slightly reducing the portions of your dinner (a meal that averages about 800 calories) then having  yoghurt for dessert instead of  ice-cream (127 calories/100g vs 246 calories/100g).

So which sounds more manageable: a gruelling stint of exercise, or small changes to what you eat?

Understanding how many calories are in food, and how little of those calories are burned off by exercise, is fundamental for those keen to lose fat — particularly because many of us are guilty of exercising and then (consciously or unconsciously) rewarding ourselves with food, thereby undoing the calories lost in the workout.

If you are aware of how many calories you’re actually burning during exercise compared to what you’re taking in from food, then you may have the willpower to say no to that 400-calorie piece of cake or other calorie laden snack. To burn off that ‘innocent’ piece of cake would take an  hour long jog – a big price to pay for that ‘innocent snack’.

Back to the question  – Is weight loss the same as fat loss?

It is true that straight out across the board calorie restriction which creates an energy deficit will enable weight loss ie. you will lose fat, muscle and fluid. But if you structure your calorie intake such that high quality proteins are consumed in accordance with your height, sex and weight requirements combined with healthy fats & plentiful low carbohydrate vegetables you will in the main lose fat while maintaining lean muscle mass. Preservation of lean muscle means that your BMR does not drop significantly while in weight loss mode, strength and integrity of muscle is maintained and your overall body shape will improve.

So is cardio necessary at all?girl running

Not always, but it can definitely assist in your fat loss journey if combined with an appropriate diet that delivers an overall energy deficit. Running, biking, swimming, and all of the traditional cardiovascular exercises may not be a necessity to your battle with the scale, but they can improve your overall quality of life significantly and definitely help maintain fat loss over time. These aerobic exercises can improve muscle endurance, heart health, and even your sex life. Don’t toss those running shoes away for good, just understand that you don’t need them to achieve the body that you desire.

A note about weights

By now, we hope that it’s clear that cardio isn’t necessary to make your gut disappear. Your diet reigns king in the world of fat loss. Strength training, however, is a valuable asset to your fat loss journey. When you lift weights, you are assisting the simple equation for fat loss in two ways;

You do NOT need  excessive cardio in your life to shed  fat. Eat less food, exercise moderately on a daily basis, lift some weights, and create a calorie deficit. It’s as easy as that. Good luck!

What’s your average calorie burn? Want to know how to create that all important energy deficit?

Muscle to fat ratioDr. Sandi’s special area of interest & expertise is nutritional medicine having assisted many hundreds of patients to shed fat and initiate long term changes in eating habits. In just 1 appointment Dr. Sandi can calculate your daily ‘calorie burn’ and design a short term plan for accelerated fat loss then set in place your long term weight management and lifestyle strategies.


This blog is general in nature only and should not be relied upon as medical advice. For further information please contact our clinic or your own medical practitioner before commencing any diet or exercise regimen.