Is cardio the best way to lose weight?

The key to losing weight is to stay in a calorie deficit. Calories are introduced into your body via food; various foods have different amounts of calories. Your body uses up these calories during the day as a source of energy and also burns them when you exercise.

Whilst diet is the most important factor when it comes to losing weight, exercise plays a role as well. You can use our calorie calculator to see this in action.

For example a 40 year old lady who weighs 100 kg, is 155 cm tall and does little to no exercise will need to eat around 1550 calories to begin to lose weight. If the same lady exercises 3 – 5 times a week and consumes 1550 calories, she will begin to lose weight at a much faster rate.

There have been numerous studies that have been carried out to determine just how effective different types of exercise are when trying to lose weight and which is the most efficient. In the simplest sense, exercise can be broken down into two categories: cardio and weight training.

What is cardio?

Cardio or cardiovascular exercise is a type of exercise that mainly focuses on your heart and lungs. Cardio can be done outdoors, at the gym, or even at home by using equipment such as an elliptical trainer.

There are many different types of cardio exercises including walking, running, cycling, rowing, skipping and swimming. If you have done any of these before you will have noticed that your heart and breathing rates went up. This is due to the simple reason that your muscles require more oxygen.

Your increased breathing rate means that you inhale more oxygen and your increased heart rate means that more oxygen rich blood is pumped to the cells that require it. The exercises mentioned in the paragraph above burn different amounts of calories, and the intensity at which you do them is also a factor. Here are a few examples:

Walking – burns around 300 to 400 calories per hour

If you walk for an hour at a moderately fast pace, you will burn around 300 to 400 calories. There are of course various factors that affect how many calories you will burn, including your current weight, the gradient of the surface you are walking on and the total distance.

For example a person who weighs 70 kg and walks 6 km in one hour on a flat surface will burn around 350 calories. If the same person walks 7 km on a surface with a 4% incline for an hour, they will burn around 575 calories.

Walking is great when just starting out because it is low impact, making it ideal for those who are obese or have an injury. It is also ideal if you enjoy exercising outside rather than in a gym.

Running – burns around 600 to 700 calories per hour

When we say running, we actually mean jogging, which is running at a comfortable pace (i.e. not sprinting). Jogging is more intense than walking and therefore burns more calories, at around 600 per hour.

However again, like with walking, the intensity, distance and gradient at which one jogs will determine how many calories are burnt. Jogging mainly uses your leg muscles. You can either jog on a treadmill, where you can control the speed and intensity, or outside.

Jogging is much higher impact than walking so may not be suitable for everyone when just starting out. You might want to combine the two and gradually transition to jogging only, as your endurance builds up.

Swimming – burns around 600 to 700 calories per hour

Swimming has often been considered to be one of the best exercises you can do because it is a full body work out. This means that it works out many different muscle groups in your body. Due to the density of water, swimming is low impact and so there is a lower risk of getting injured.

If you swim for an hour, you will burn around 600 to 700 calories. Again, your current weight and the intensity at which you swim will determine the total number of calories used.

Jumping rope

Jumping rope, when done correctly, is one of the most intense forms of cardio you can do. It works your legs, arms & core, and helps build balance, stamina and speed, which is why it is so popular with boxers.

Due to its intensity, jumping rope can burn up to 1000 calories per hour. However because it is quite high impact and requires a fair amount of practice and skill, most people will only be able to do it for 10 to 20 minutes. It is important to have proper technique and wear a good pair of shoes.

High intensity interval training (HIIT)

When most people think about cardio, they think more in terms of how it is described in the section above – relatively long and steady periods of exercise such as swimming at the same pace for an hour.

However there is another type of cardio known as high intensity interval training or HIIT. This involves alternating between super intense and standard paced exercise. Running as fast as you can for 30 seconds followed by jogging at a slow pace for a minute, and repeating this routine for 15 – 30 minutes is an example of HIIT.

The difference between steady state cardio and HIIT is that the former is an aerobic activity whereas the latter is anaerobic. What this means is that they use different sources of fuel.

There have been various studies that show HIIT to be more effective than cardio when it comes to fat loss. For example this study involved 45 overweight women who were split into two groups, regular cardio and HIIT.

The regular cardio group cycled for 40 minutes at a steady pace whereas the HIIT group cycled for 20 minutes, switching between cycling “all out” for eight seconds and then twelve seconds of light cycling. The women in the HIIT group ended up losing 3 times more body fat than the regular cardio group.

HIIT has a tremendous effect on your body and because of this you burn fat and calories up to 24 hours after you stop exercising. So even if you are sitting and doing nothing the day after a HIIT work out, your metabolism will be ramped up.

The benefit of HIIT is that you are able to achieve better results than you would with steady pace cardio, in a fraction of the time. However at the same time, HIIT is much more intense meaning you will feel exhausted much faster and need more time to recover than regular cardio.

What about weight training?

Training with weights has many benefits, but is it effective when trying to lose weight?

In this study 304 participants were divided into 4 groups and followed one of 4 plans for 22 weeks: aerobic training (cardio), resistance training (weights), aerobic and resistance training (weights & cardio) and no exercise. All of the participants stayed in a 250 calorie deficit.

The results showed that all three exercise groups lost more body fat than the control group. The aerobic group saw an average decrease of 1.1% of body fat, the resistance training group a 1.6% decrease and the combined group a decrease of 1.4%. However, those in the combined group saw a larger decrease in waist circumference compared to the other two groups.

The added benefit of weight training is that it helps you build muscle, which is much more compact than fat. People with more muscle also tend to have higher metabolisms which means they burn more fat and calories in the long run.

I am sure that your goal is not just to lose weight but to also have a toned, lean body. In order to get that kind of body, you need to lift weights.

When trying to lose weight, it is better to look in the mirror rather than just relying on a weighing scale. This is because as you continue to train with weights, you will build more muscle, which has mass. So whilst the weighing scale might disappoint you, looking in the mirror won’t because you have essentially “converted fat into muscle“.


If you want to lose weight, I would personally advise you to do both cardio and weight training. If you are able to, add in some high intensity interval training as this is very effective when it comes to burning fat. If you find it difficult at the beginning, don’t overwork yourself. Instead, gradually build up your endurance.

The most important thing to note when trying to lose weight is that you need to watch your diet. You can do as much cardio and weight training as you want but if you are constantly consuming more calories than you are using up, you will not lose weight. Cut out soda, candy, other processed & deep fried foods and replace them with water and real foods such as fresh vegetables and lean meat.

For more weight loss tips, read our article here.

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