How long should I workout to lose weight

A member of the weightloss forum recently asked what the recommended amount of daily exercise is to successfully lose weight. Interestingly, the answer to this simple question is anything but simple. Having said that, we're going to try to answer it as simply as possible so we can all determine the right amount of exercise for us and take one step closer toward achieving our weight loss goal.

Isn't twenty minutes of exercise, three times a week enough?

Most of us have heard that exercising three times per week for 20 minutes each time is enough. But is it really?

The answer for most of us with weight loss goals is no, here's why:

This recommendation is actually a 'minimum' of three times per week for 20 minutes each time.
This recommendation was made to encourage people who get no real exercise at all to do just enough to improve their cardiovascular fitness (increase the strength of their heart and lungs).
This recommendation was made knowing that to recommend any more exercise would serve to discourage rather than encourage the least active people to get more exercise.

For those of us who believe that this amount of exercise can help us lose a significant amount of weight alone are in for a bit of a shock. The amount of exercise needed for significant weight loss is far more than that needed by otherwise average weighted people who work at computers all day and drive everywhere who want to slightly improve their fitness. For significant weight loss this amount of exercise alone just isn't enough.

So how much exercise is it going to take?

To answer this question we first need to ask another "what is your goal?", or more specifically, "how much weight do you want to lose and by when?" Once we have the answer to this second question, we can simply calculate how much exercise is needed based on an understanding of how much energy different exercises burn per minute. Here's an example of how we do this assuming that our goal is to lose 10 kilos in 20 weeks, or ½ a kilo per week:

The amount of exercise needed to lose ½ kilo of body fat per week

Before we begin this example, please note that the figures used are guides only that have been rounded slightly up or down to make them easier to read and remember. It has been estimated that ½ kilo (1 pound) of body fat equals around 16,000 kilojoules (or around 4,000 calories). So to lose ½ kilogram of body fat each week through exercise, we need to burn off approximately 2,500 kilojoules (600 calories) extra each day. So based on this figure, the answer to how much exercise is easy: that amount of exercise which burns an extra 2,500 kilojoules (kJ) per day, or 16,000kJ per week.

Using the energy charts provided on this website as a guide, the amount of exercise needed for a 100kg person (the amount of energy burned during exercise varies depending upon the body weight of the exerciser) to burn the total 16,000kJ per week equate to:

Approximately 10 hours of walking at 5kph (3mph) per week - or 90 minutes per day.
Approximately 4 hours of jogging at 10kph (6mph) per week - or 35 minutes per day.
Approximately 4½ hours of cycling at around 20kph (12mph) per week - or 40 minutes per day.

So, if the same 100kg person walked only three times a week for twenty minutes each time, they would only burn 1,500 kilojoules. That's more than just a few short of the 16,000 needed isn't it! Even if they walked for 30 minutes everyday, they'd still only burn 5,200kJ per week! Of course, these amounts assume that we want to lose all of our weight by exercising alone. If we are happy to rely on dietary changes to contribute half the energy required (8,000kJ per week) for example, we can halve the amounts of exercise listed above.

The 'complex' part of the answer

Remember at the outset of this article, we said that the answer to the question "how much exercise?" was a complex one, but the answer provided above isn't really that complex. The reason for that is the above example is only part of the answer. Because peoples lives are so different, weight loss can't realistically be reduced to a simple equation like it has been above. There are other variables to be considered in the amount of exercise for weight loss equation that weren't adequately catered for in the above example.

For example, none of these factors were taken into consideration:

Our individual weight loss goals
Our individual levels of motivation
Our individual fitness levels
Our individual energy levels
Our time availabilities
Our priorities in life
Our preferred exercise program
Our commitment to exercise progression
Our attitude towards exercise
How consistently we exercise
Our general physical abilities
The law of averages
How many kilojoules or calories less we are prepared to eat each week

Before we take a brief look at each of these in turn, it's also important to remember that for every one of us, all of these factors are subject to change from day to day, week to week, month to month and year to year.

Our Goal

Because each of us has different goals, the amount of exercise which is right for each of us will be different.

Some of us may want to lose a total of 20-30kgs in 12 months while others may only want to lose 5-10kgs over the same time frame for example.

Our level of motivation

There are many different motivations to lose weight, such as looking better, feeling fitter and stronger, overcoming or avoiding weight related illnesses and medical conditions, wanting to be able to play with children, fitting into the ideal wedding dress, to name but a few.

What, and more importantly, how strong our motivation levels are will help to determine how much of the exercise we know we need to do we actually will do.

Our current fitness level

How fit we are today determines to a great extent the amount of exercise we can realistically do and just as importantly, at what level of intensity.

Of course, this variable can change significantly if we do exercise even a little bit and build progression into our workouts (exercise longer and/or at greater levels of intensity) as we get fitter.

Our individual energy levels

Like our fitness level, our energy levels will help determine how much exercise we can cope with each day. Ironically, the more we exercise the more energy our bodies will have available to exercise. This is one of the reasons not to get depressed by the amount of exercise required to lose weight - because although we won't be able to do all of that exercise right now, if we do what we can, that amount will grow over time.

Our time availabilities

Some of us have more time to dedicate to exercise than others.

If we can and would like to exercise for an hour or two each day but don't physically have the time available, we might need to get a little smarter (such as including the family in our exercise , exercising before the family wakes up in the morning, during our lunch-break, or after the kids have gone to bed), exercise more efficiently (for example jogging instead of walking) or reevaluate and set new priorities.

Our priorities in life

Many of us believe that there are more important things in life than exercise. With this believe, is it any wonder that many people don't exercise at all? Some people even think that time spent exercising is selfish and extravagant. Nothing could be further from the truth. The reality is that nothing is as important as our health and wellbeing, because with these in place we can literally do anything. And just as importantly, anything we do do will be done and enjoyed that much more because we can do them that much better when we are physically fitter and stronger.

Our individual exercise program

The exercise we chose to do also helps determine how much is necessary long-term, and how much we will actually do. Some exercise burns more energy than others and some have a longer lasting effect on the amount of energy our bodies burn even while resting.

For the best possible long-term benefit, a program that includes aerobic type exercises (like walking, jogging, bicycling, swimming, martial arts, etc) and strength training exercise (like weight training, isometric exercise, resistance band exercise, circuit training, etc) works best because the aerobic workouts burn the maximum amount of calories during the workout and the strength training increases our resting metabolic rate (or the amount of energy our body burns at rest and during everyday activities).

In addition, how stimulating our exercise programs are mentally and physically will help determine how much we want to do and how much we actually do.

For this reason, it is important to find exercises we enjoy, that challenge us, that can be progressive in terms of intensity and that are as varied as possible.

This is where personal trainers, having a variety of exercise equipment, joining a gym or fitness centre, or building up a library of exercise videos or DVD's and the like can help.

Our commitment to exercise progression

We've already touched on this one briefly, but it is important to know why progression is such an important part of any exercise program, particularly when it is designed for weight loss.

Exercise progression is important for weight loss because:

As we lose weight, we burn less energy doing the same exercise - because we are physically carrying less weight around.
The fitter we become, the more efficient our bodies become and the less energy they use to do the same volume of exercise.

Our attitude towards exercise Our attitude towards exercise is one of the most important determining factors in how much exercise is right for us.

If we have a negative attitude towards exercise, we need to undertake a little bit of self-discovery and uncover exactly why we have a negative attitude towards it, and then set about turning our negative attitude into a positive one.

For example, if we don't like exercise because it's too hard, we need to take it very easy to begin with and not be too hard on ourselves to progress too soon.

Remember, doing something is better than nothing and it is far easier and more likely that we will progress from doing a little bit of exercise to a little bit more, than it is from doing nothing to doing a whole lot!

How consistently we exercise

Not too many of us will be able to do exactly the same amount of exercise each day or each week. Within the constraints of life's natural daily, weekly, and monthly cycles, we need to be as consistent as possible for the best long-term affects. For example, it would be better for us all if we walked for twenty minutes everyday for the rest of our lives than it would be to run 20 kilometres today and then never exercise again.

While exercise consistency will mean different things to each of us, the most important things we can do to ensure that we exercise consistently are to:

Make exercise a habit and part of our daily or weekly routine.

Make sure that regular exercise seamlessly fits into our total lifestyle.

Make sure that exercise is a high priority in our lives.

Our physical abilities When it comes to exercise, some of us have physical disabilities that prevent us from doing some forms of activity. Sometimes these disabilities are permanent or long-term, and sometimes they are short-term (such as those that result from soft-tissue injuries for example). The key to dealing with any disability is to try and find ways around them as best we can given our individual circumstances. To do this we may need some help from specialists like doctors, osteopaths, massage therapists, etc.

The law of averages

The law of averages suggests that if we need to average 60 minutes of exercise everyday (for example), we should perhaps do 70 or 80 minutes per day knowing full well that it is unrealistic for any of us to be able to exercise every single day. One great way around this dilemma is to do double the amount of daily exercise we need on one day per week (such as Sunday for example) when the demands on our time are a little less or a little more flexible.

How much we are prepared to cut down the kilojoules or calories we eat

The most effective and efficient way to lose weight is by combining the effects of eating less and exercising more.

How much of the total burden each of these elements contributes to us achieving our ideal weight will depend solely on personal circumstances and preferences.

For some of us, the path of least resistance will be to rely mostly on diets to help us achieve our ideal weight.

For others, sever dietary changes are not the preferred option and these people will be happier to exercise more in order to continue enjoying their favourite foods (but hopefully a little less of them!). The most important thing here is to understand how much energy in total we need to be in deficit (shortfall) each week in order to achieve our weight loss goal in the timeframe chosen, and then plan accordingly.

To help us with the dietary side of the equation, we might consider consulting with the likes of a weight loss specialist, registered dietitian or nutritionist.

One great way to keep track of energy in and energy out each week is by keeping a weight loss journal, or an exercise or food diary.

To understand how much energy your body needs to maintain its current weight, please visit our Daily Energy Needs Calculator page.

Conclusion

A new member to the weightloss forum recently asked what the recommended amount of daily exercise is to successfully lose weight. Interestingly, the answer to such a simple question is anything but simple. We've tried to provide some information in this article to help you to determine the right answer for you, and we're sure after reading it that you now know that it is much more than many of us think it is. Good luck with your exercise and weight loss and thanks for visiting weightloss.com.au.

This article was written by Scott Haywood.

Scott is the editor of weightloss.com.au. Scott has developed an expertise in fitness and nutrition, and their roles in weight loss, which led him to launch weightloss.com.au in 2005. Today, weightloss.com.au provides weight loss and fitness information, including hundreds of healthy recipes, weight loss tools and tips, articles, and more, to millions of people around the world, helping them to lead happier, healthier, lives.

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