When your goal is to lose weight then it is necessary to create a “calorie deficit”, that is, the calories you use for exercise and daily activity is greater than the calories you eat each day.
Everybody has ‘X’ number of calories to burn each day just to maintain their current body weight. When you go further than this and create this calorie deficit, your body responds by burning more calories, muscle and fat to meet this demand for energy.
So how do we create this calorie deficit?
The most obvious answer is “eat less and exercise more”. You need to do something with the energy created by the food you eat and at the same time, make sure that the amount of food you eat is kept to a level below what you burn up each day.
If you are totally confused by this then don’t worry. I don’t advocate calorie counting, it is too time consuming and mentally draining and will just leave you thinking about food all day long, which is the opposite of what we are trying to achieve.
Achieving this calorie deficit is not as hard as you may think, especially when you know how your body uses energy from the food you eat.
Your brain requires quite a bit of energy just to get through the day. Glycogen is what your body converts carbohydrates into and your brain feeds off this to stay alert, awake and functioning at a high level each day. Have you ever felt tired or drowsy when you have not eaten for a while? Or have you ever tried a low carbohydrate diet and felt lethargic? This is because your brain is literally starved of energy and is slowing down to a halt. This demonstrates just how much energy your brain uses and that burning through the calories you eat is assisted by just being awake and functioning.
Now what about the rest of the equation? How do we create a significant calorie deficit? Eating less is an obvious answer but cutting food down too much will slow your metabolism and bring your weight loss to a halt. Too few calories will mean your body will go into panic and adjust your metabolism accordingly by holding onto as much fat as possible. You cannot outsmart your body!
Cardiovascular exercise is a key ingredient to weight management. It burns a lot of calories at once and keeps your metabolism going and your heart healthy.
So what is cardiovascular exercise, or “cardio”?
Any exercise you do that raises your heart rate for an extended period of time is cardiovascular activity.
Walking, running, jogging, riding, swimming, skipping are all forms of cardio. They require you to maintain a constant state of movement which raises your heart rate and burns energy.
These activities are all “steady state” forms of cardio. They elevate your heart rate and keep it up there for an extended period of time. This is the easiest way to create a calorie deficit. Steady state cardio will demand your body releases calories for energy to keep you going and if you go long enough and at the right intensity it will tap into your fat stores.
There are some guidelines you need to meet to make cardio effective, because too much, too little, too intense or not hard enough can waste your efforts.
Type
The type of exercise you choose is extremely important. Some forms of cardio are more effective at getting your heart rate up than others. For instance, running is a very good way of raising your hear rate, but if you are not conditioned enough it may raise it too much.
Choose a type of cardio that is best suited to you and will make you work at the right level of intensity.
Walking is great, but not strolling. You need to walk pretty fast to elevate your heart rate and if this does not work for you then consider jogging. Swimming and bike riding are also cardio but it can be difficult to maintain a steady, constant heart rate for an extended period.
I would always choose walking and running first. It is easier, more convenient and more effective at getting your heart rate up and keeping it there.
Time
You need to spend enough time performing your cardio to benefit from it. Your body takes the carbohydrates you eat and fills your muscles up with glycogen. This is what gives you energy and allows you to exercise for longer and more intense periods. You need to exercise for long enough to deplete the glycogen levels in your muscles to tap into the fat stored in your body.
How long is this?
It depends on several things such as how much you have been eating, the type of food you have been eating, as well as your metabolic rate. But it can take 20-30 minutes of cardio exercise at a solid level of intensity before running down these glycogen stores. So aim to get 45-60 minutes of cardio done each time.
Intensity
The intensity of your exercise refers to how hard you are working. It is important to get this right when performing steady state cardio and measuring your heart rate in beats per minute is the best way to do it.
You want to operate at a heart rate of about 65-75% of your maximum heart rate for an extended period of time. This level of intensity will ensure you are working hard enough to use the stored glycogen and give you the best chance of using body fat stores for energy.
It will also ensure you are not going too hard. If you push too hard you will not last long enough and/or you will just burn muscle for energy, which is not what we want.
You can measure this on the spot with the following equation:
Maximum Age Related Heart Rate x 65-75% = Optimum Heart Rate for Cardio
Take 220 and subtract your age (ie if you are 48 subtract this from 220 = 172)
This is your maximum age related heart rate. Now find 65-75% of this (172 x 0.65 = 112 and 172 x 0.75 = 129).
So the best range for you to work at is a heart rate between 112 and 129 beats per minute.
Wearing a heart rate monitor is the easiest way to monitor this, however you can easily stop every so often and take your pulse (at the carotid artery under your neck) and monitor your heart rate.
You will easily determine the best form of cardio for you by keeping a close watch of your heart rate. This will help you decide if walking is not intense enough for you or if running is too intense for you.
Cardio is a fantastic form or exercise and is essential to burning fat and ensuring you get that calorie deficit that is needed to lose weight.
About the Author
Ryan Mitchell is the owner of Evolution Fitness Centre and is a qualified personal trainer and strength and conditioning coach. Ryan is dedicated to helping people achieve their health and fitness goals and draws on his experience and knowledge gained from training people of all ages and fitness levels. Ryan is a former Australian Powerlfiting Champion and Australian team member.
