When most people make a decision to lose weight they will buy a pair of trainers and start jogging.

It’s a matter of convenience. Running shoes are relatively cheap and can go with you anywhere. You can put them on at any time and exercise without having to find a gym. Just about anybody can do it, and it can help people lose weight because physical activity burns calories.

Burning more calories than you consume means that you will lose weight. In fact, creating a calorific deficit is the only way to lose weight. Yet, cardiovascular exercise isn’t the best way to create a deficit. It is far more effective to control how many calories you consume in the first place by cleaning up your diet.

Only after you have a solid diet in place should cardio be introduced to help burn fat at an accelerated rate.

Jogging is a good starting point, but it is not the only method of cardio, nor is it necessarily the best. Under the wrong circumstances, too much cardio can even hinder you. Fortunately, there are numerous ways of performing cardio to meet differing goals; whether that’s losing weight, improving endurance or even building muscle.

The type of cardio you choose to perform should be both enjoyable and help you reach your goals. Too much cardio is anything beyond that.

So which type is best for you?

Generally speaking, there are three categories of cardio that are each appropriate in different situations:

Low Intensity

Hiking the Tongariro Crossing in New Zealand

Activities that fall into this category include walking, hiking, a casual bike ride, a light swim and even household chores like mowing the lawn. Unless you’re severely out of shape, you should be able to have a conversation whilst doing any of these (well, maybe not whilst swimming, but you get the idea).

Depending on how fit you are, low intensity aerobic activity involves working at 55 to 75 percent of your maximum heart rate.

Those who live by the ‘no pain, no gain’ mantra might not even consider this type of activity to be exercise, but the truth is that low intensity exercise is hugely beneficial in its own right.

For those who are out of shape, or are returning from a fitness hiatus, it provides a foundation that makes more strenuous workouts possible. By preparing the muscles, joints and connective tissue you are able to perform strength training and aerobic activity at optimum levels.

Specific studies have found that it also reduces the risk of metabolic syndrome, cardiovascular disease, dementia, overall systemic inflammation, and helps to improve our mood for some time afterwards. It can even help speed along recovery from strenuous activity by increasing blood flow to the muscles.

As far as weight loss is concerned, low intensity cardio is particularly useful for people who want to build muscle. Unlike moderate or high intensity exercise, it doesn’t really stress the body, which makes it easy to recover from. It can be performed daily alongside a vigorous weight lifting program (3-5 days a week) to help burn fat and accelerate recovery.

The only real drawback of low intensity cardio is that it takes a long time. If you do have the time, however, it can be an extremely effective way of burning fat without impeding recovery from other, more strenuous, activities. Anywhere between 2-5 hours each week is highly beneficial.

Do low intensity cardio if:

• You regularly train with weights and do not want to impede your recovery.
• You have a lot of time on your hands.
• The psychological benefits are important to you.

Moderate Intensity

For one reason or another moderate intensity exercises have become the default choice when people take up exercise, and the exercises in this category are what come to mind when most people think of cardio. Running, cycling and swimming for prolonged periods of time all fit in here nicely.

Typically, you will be exercising at a moderate intensity when your heart rate is in the range of 70 to 80 percent of your maximum.

Moderate intensity, like low intensity exercise, offers many health benefits that result in decreased mortality risks. Yet, unlike low intensity, moderate intensity exercise stresses the body to the extent that you need time to recover between workouts.

Unfortunately, people sometimes make the mistake of doing too much of it, or combining it with a diet that doesn’t provide enough calories to facilitate recovery. This sort of behaviour amounts to overtraining.

Overtraining is defined by the American Council on Exercise as ‘constant intense training that does not provide adequate time for recovery’.  If you are unable to recover from your workouts you will find it extremely difficult to improve from one workout to the next, and sooner or later it will result in injury.

To illustrate this point consider this study that monitored the body composition of athletes in the trans-europe run where they ran 2800 miles in 64 days (an average  of 43 miles a day). They did not lose any muscle mass in their upper bodies, but lost a great deal from their legs. Their legs did not have chance to recover between bouts of exercise and as such became weaker.

Often, people who are trying to build muscle will avoid cardio for fear of sabotaging their ‘gains’. The study, however, makes it clear that cardio is only problematic when it involves overtraining of a particular muscle group. Cardio has an unfair reputation for burning muscle because people often couple drastic diets with cardio in an attempt to ‘cut’ after ‘bulking’ (an old school bodybuilder mentality). The combination of cardio and a severe caloric reduction is responsible for muscle loss, not the cardio alone.

If moderate intensity exercise is something you enjoy it is important that you choose to do it on days that do not follow or precede other forms of leg training (squats, deadlifts etc). Additionally, you should ensure that you are eating enough calories to facilitate recovery.

Do moderate intensity cardio if:

• You’re training for some sort of endurance event (think Tough Mudder, a half or full marathon, or a triathlon).
• You really like running, cycling or swimming, whether that be indoors or out.
• You can dedicate lots of time to training.

High Intensity

High intensity exercises have one thing in common: alternation between periods of rest and explosive activity. You may have heard of interval training (HIIT), but sprinting, Tabata and circuit training are all methods of performing high intensity cardio too. 

Most exercise performed above 80% of your maximum heart rate will be at a high intensity. You might find that it feels like a volcano erupting in your lungs.

A typical high intensity workout could involve 20 seconds of running as quickly as you can, immediately followed by 60 seconds of rest, over 10 cycles. This might take 20 minutes. This type of training not only burns a lot of calories in little time and builds up your oxygen capacity whist exercising, but it can also produce an afterburn effect. This afterburn can leave your metabolism operating at a higher level of efficiency for up to 24 hours after exercising.

This means that you will be burning calories for the rest of the day, even after you have finished exercising.

As if that wasn’t enough, high intensity exercise also helps create an anabolic effect (which helps you build muscle), improves insulin sensitivity and increases aerobic capacity.

Although your body will be burning calories for a long time after exercising, it will also be trying to recover. High intensity training is much more taxing than low or moderate intensity exercise, so you should limit it to 3 short sessions each week. If you can do it for longer than 20 minutes, then you probably aren’t pushing yourself hard enough. The best time to do high intensity training is immediately after a weight lifting workout, or on a day that does not follow or precede other forms of leg training.

Do high intensity exercise if:

• You want to burn a lot of calories in as little time as possible.
• Building muscle is a priority.
• You like pushing your body to its limits.

How Much Cardio Is Too Much?

How much cardio you should be doing really depends on your goals, how much time you can devote to exercise, and most importantly, what you enjoy.

It’s up to you to find a combination of the above that makes you happy and keeps the weight off consistently.  Fortunately, there’s no perfect way to get in shape, so find something that works for you and stick with it. If you want to:

• Build Muscle – Try out low intensity cardio to burn calories without impeding recovery, or high intensity exercises to help create an anabolic effect in the body.
• Lose Weight – Start with low intensity exercise and work your way towards high intensity exercises like sprints to burn fat in little time.
• Improve Endurance – Go running, cycling or swimming and try varying the speed and intensity to challenge yourself.

If you’re looking for a high intensity workout, sign up for the newsletter and get the Beginner Bodyweight Workout for free. The ebook contains a high intensity bodyweight circuit that will help you torch fat and build muscle at the same time!