The best way to lose weight – The power of exercise

The best way to lose weight – The power of exercise

The best way to lose weight is multifactorial. No single method rules the roost and we know losing weight can be tough. In fact, many of my patients can’t understand why they can’t lose weight despite their best efforts.

I see a lot of people wanting to lose weight and I can honestly say the overwhelming majority of them lack the appropriate exercise.

Losing weight without exercise is possible but it’s less sustainable in the long term. Think of exercise like a tool in the weight loss tool box. Without it, you might still be able to do the job but it will be much harder.

This prompted me to want to write this blog about how exercise is the best way to lose weight. It is the most sustainable way without any doubt in my mind. Throughout the post, I’ll show the difference between someone who is active and someone that is not. I’ll show you why this is often the difference between long term weight loss success and long term failure.

It’s no good losing weight if you then put it all back on. Therefore, what I’m referring to in this post is long term sustainability. This is what will benefit your health and prevent long term health complications.


My patient nervously eyes the scales. Mouth slighted parted, we’ve been here before. Surely this time will be different. As he steps onto the scales to record his latest weight the numbers jump around before finally settling. Seemingly holding on for dear life he looks down. It’s bad news. He’s gained 1kg since our last appointment. This follows his trend of having minor successes followed by major disappointments. Why can’t I lose weight he asks in a rhetorical manner but I know he’s actually asking.

Why can’t I lose weight is possibly a question that keeps me in a job. A lot of my patient referrals are for people who seemingly cannot lose weight. Despite their best efforts, the pounds just won’t melt away.

It can be frustrating for my patients. They have often yo yo’d for years with their weight and seem unable to crack the magic formula.

They’ve made dietary changes and think they are doing all the right things. Yet it’s to no avail.

What these patients don’t realise is this is very common. In fact I see people in this situation almost daily. All these patients who struggle display very similar problems and I can see exactly why they aren’t losing weight. Sometimes we have frank discussions, other times I need to tread a bit more sensitively so not to alienate the patient.

It’s a fine line. I could tell every patient I see exactly what they need to do to lose weight. However, it just doesn’t work like that. You often end up annoying people with that approach and so you need to be a bit more sensitive and patient centred. Instead, the better approach is trying to get patients to come up with their own solutions and I tend to more facilitate.

However, in a blog format, I can just lay it all out there and I thought it might be an interesting read for some of you.

So today I wanted to discuss the most common reasons why my patients cannot lose weight.

Lack of exercise

Let me be clear. I’m specifically referring to activity that increases your heart rate. Pottering around the house does not count here I’m afraid. I say this because this is a frequent response I get when asking patients about their activity levels. I’m sure they are busy but the physical activity they often describe is more mentally draining rather than physically challenging. If I’m honest, when it comes to weight management, I think some people say this to convince themselves they are doing more than they are. If pressed, they might admit they could do more.

However, what we’re talking about here is active exercise to get your heart rate up. This in turn makes your body start to burn energy. Already this establish a crucial element to the weight loss formula.

There will be those of you who straight up do no exercise. Maybe you’ll walk a little bit but your overall activity is low. A good test to see if this is you is go into the health app on your smart phone. In there, there will be a step tracker. Granted you won’t have your phone on you 24/7 but it’s a good bench mark. If this is below 5000 steps and you do not other exercise, you’re inactive. In fact, you probably need to be doing at least 10,000-15,000 steps per day for weight loss if you’re doing no other exercise.

If you do exercise but aren’t seeing the results there’s 2 things to look at. First your diet (although this always applies as exercise and diet are interlinked). Second the frequency, intensity, type and time of exercise (more on this shortly).

As this post is about exercise, we’ll focus on the exercise components. The diet side of things is covered extensively elsewhere on this blog.

Let’s examine some of the theory as to why exercise is the best way to lose weight before getting onto a practical example.

Frequency, Intensity, Type and Time of Exercise

These are the variables we can breakdown when it comes to exercise. To explore why exercise is the best way to lose weight we need to understand the basic principles behind it. Let’s take a look at the four variables individually.


The more often you do something the better you will get at it. Frequency refers to how often you are exercising. This might be once a day or once a week. The more often you do exercise the more likely you are to benefit from it.

If you are unable to exercise for long periods or at high intensities, you might need to think about how often you will exercise. It is beneficial to split exercise sessions into segments if you do not have the fitness to do it all in one go.

Therefore, doing exercise regularly can compensate for an inability to do high intensity or long durations.


It’s easy to just go through the motions when exercising. Some exercise is better than no exercise but intensity is very important. Lower intensity activities like walking take much longer to burn calories. So you have to do activities like this for a long time. As I said earlier, it is estimated you need to walk around 15,000 steps per day if doing it specifically for weight loss. That’ll take about 2 – 3 hours for most people. You can spread this out though.

Higher intensity exercise can be shorter duration because you burn more calories per minute. The trade off is it is harder.

One mistake I see patients make is they exercise a couple of times per week and do fairly low intensity exercise. This might be something like aqua aerobics or light resistance training where they rest between each set. Again, this is better than nothing but the overall calorie expenditure is low. This can make people think they are doing more than they truly are.

Therefore, for weight loss (not necessarily health) you need to do harder, longer or more frequent sessions.

Excess Post Exercise Oxygen Consumption (EPOC)

I will do a separate blog on this but it’s worth mentioning here. EPOC is the extra calories you expend through a raised metabolism even after stopping exercise. If you do a high intensity or large effort exercise session, it takes your body a while to settle back to normal. There will be a period afterwards where you continue to expend calories.

EPOC could account up to 15% of the total calories burned from exercise. That’s a fair chunk. A 60 minute run that burns up 700kcal will actually burn a further 95kcal for nothing.

This effect is intensity and duration dependent. A good analogy is like travelling in your car in a 30mph/hr zone. This is your baseline metabolism. You then hit the motorway and put your foot down. You move from 30mph to 70mph. It’s quite an increase in speed. Once you leave the motorway it’s back to a 30mph zone and thus baseline. Had you increased to only 35mph, the increase from baseline to 35mph is lower than 70mph and therefore you return back to baseline more quickly.

Therefore, you will not get the benefit of EPOC if you only dabble with very low intensity exercise for short durations. In order to make exercise one of the best ways to lose weight, ideally you will achieve some form of EPOC effect by lengthening the session or increasing the intensity.

Time and Type

Just because you do some exercise it doesn’t mean it is enough to induce weight loss.

Whatever you do is better than nothing. No doubt about that. However, if substantial weight loss is your goal, it might mean upping your game.

Time is quite straight forward. How long is each session. If time is low, intensity tends to need to be high. If time is high, you can ease off the intensity. Without understanding this basic concept, you will struggle to use exercise as a tool to help you lose weight.

Type refers to the many different training methods available to you. There are hundreds of different activities. I think the most important thing is finding one you like.

Ideally the type of exercise you do will be a mixture. Some cardiovascular work mixed in with some resistance and mobility.

What is enough exercise to make exercise the best way to lose weight?

This will depend on the person and what weight you want to be. I tend to shy away from using myself as a case study but in blog format I suppose it’s the only point of reference I have.

For me, exercise is definitely the best way to lose weight. That said, I eat quite healthy anyway. However, I certainly notice the difference between being active and inactive.

I personally exercise a minimum of 4 days per week. I was better in my 20s going for an average of 6 but life is now happening to me. Ideally I aim for 5 sessions. This activity varies. I’m quite injury prone and have some back and hip issues which seem to run in the family. So I’m limited in what I can do. Lower body exercises such as weights, burpees and intense spin classes are out. They induce a kind of leg paralysis that only shifts after some serious and torturous time on the foam roller and stretching.

Therefore, I focus on what I can manage. I do upper body resistance training with some body weight lower body stuff such as single leg squats. Sometimes I run and cycle where I can. I dabble in sport like squash. I also try circuit training when my back allows. Sessions last between 30-90 minutes usually with an average of 60 minutes. If the sessions is hard, I don’t mince about. I get my heart rate up and work off an intensity where conversation is difficult to maintain. Other times I’ll go slow and steady but for much longer. Like when I get on my bike and head out into the forest.

Not everyone will be able to work off high intensities but keep in mind intensity is relative. My 70% of max will look very different to someone else’s. The important thing is to try to get the heart pumping. If you can’t do that, then you need to lower the intensity and do it for longer.

Ultimately, your weight will tell you when you’re doing enough because it will start to move downwards.

Why is lack of exercise a problem for losing weight?

When calculating how many calories a person needs each day to stay the same weight we look at 3 factors. First is their basal metabolic rate (BMR). This is your baseline calories your body needs just to maintain itself. Things like your heart beating, lungs breathing and kidneys working all require energy. You will also have a certain amount of fat and muscle mass. These both require calories to sustain them. This is why bigger people, need more calories each day. There’s literally more of them and therefore it requires more calories to sustain them.

Next is the thermic effect of food. How many calories does it take to digest food. Third is exercise. We estimate exercise using a physical level level (PAL).

Together it looks like this:


PAL can be very modest for someone who doesn’t exercise compared to someone who does. Let me show you a quick example using Sally.

Sally has had her BMR calculated as 1500kcal per day. The thermic effect of food is 100kcal. Therefore, we have a total so far of 1600kcal for Sally to stay the same weight .

We can then apply a PAL to her calorie requirement. Inactive people receive a modest PAL factor – perhaps between 1.1-1.4 depending on the level of inactivity. We’ll go for 1.3 in this example.

Active people receive a much higher PAL score. Someone like myself would likely get about a 2. Lets see how the calories stack up.

1600 X 1.3 = 2080kcal/day to remain the same weight for Sally when inactive.

1600 X 2 = 3200kcal/day to remain the same weight due to an increased exercise load.

Losing weight with exercise

We can see how Sally’s daily calories compare if she remains inactive or if she followed my exercise regime.

UK weight management guidelines such as NICE recommend aiming for a reduction of 600kcal per day to help people lose weight. This isn’t perfect but it’s a good rule of thumb.

2080kcal – 600kcal = 1480kcal/day

3200kcal – 600kcal = 2600kcal/day

Which option do you think is easier to lose weight from? 1480kcal is quite restrictive. Some of you might think you barely eat this anyway but trust me, we notoriously under estimate our calorie intake and over estimate our exercise.

Option 2 literally allows Sally to eat almost double the calories and still lose weight. Already this is looking like the more sustainable option. It already looks like a better way to lose weight and keep it off long term.

Therefore, exercise is really the big modifiable factor here and thus we can change our above graph to look like this:

Metabolism for losing weight

How BMR sabotages your efforts for losing weight

The next factor you need to consider is BMR. Brace yourself, you probably won’t like this. Remember I said BMR is to keep your body going independent of food and exercise. Well your current BMR assumes you stay the same weight. If you start to lose fat and/or muscle mass there is physically less of you. Therefore, there is physically less to maintain now. So your BMR is lowered.

In other words, as you lose weight your BMR will be lower. This means you need to eat less to induce weight loss. Let’s return to Sally. She has lost an impressive 10kg on her lifestyle change. As a result her BMR has reduced to 1400kcal/day. How do the numbers now look with exercise added.

1400 X 1.3 = 1820kcal/day to remain the same weight for Sally when inactive.

1400 X 2 = 2800kcal/day to remain the same weight due to an increased exercise load.

This means to lose weight using our rule of 600kcal Sally needs to eat the following:

1820kcal – 600kcal = 1220kcal/day

2800kcal – 600kcal = 2200kcal/day

Option 1 is starting to look quite unrealistic to sustain for the long term. In fact, I’d liken it to a ticking time bomb. At some point Sally is going to relapse. There’s only so much someone can keep cutting back on their eating before falling off the wagon.

With option 2 however, Sally can actually eat more calories for weight loss (2200kcal) than she can in option 1 for weight maintenance (1820kcal). This is much more sustainable. Sally can enjoy an abundance of food and still lose weight.

This is the power of exercise.

Resistance training might help

One strategy to help you become even more successful with weight loss is utilising resistance training. Remember, besides the energy needed for your internal organs BMR is dictated by fat mass and muscle mass.

By definition, your lifestyle change is designed to rid yourself of much of that fat mass. Inevitably you will also lose some muscle along the way too. This then lowers your BMR. However, with resistance training you can preserve some of this. This leads to a higher BMR. It will be a small amount of calories each day you maintain but 1) it adds up over time and 2) every little helps. Even just 100kcal/day extra through BMR adds up to 700kcal per week. This is more than a full day of dietary restriction according to NICE guidelines for free!

Don’t forgot building muscle is also good for you. This is your functional component of your body. As people age, they lose muscle mass. Remaining strong and functional benefits you way beyond the scales.

I wouldn’t personally rely purely upon resistance training 100% to help me lose weight. However, it’s an integral piece of any exercise plan.


The idea of this article was to show you how exercise can be the best way to lose weight. The most important tool in the tool box if you will. Anyone can achieve quick weight loss. It’s long term sustainable weight loss that is difficult and exercise helps with that no end.

I’ve not touched on diet much in the this post but there’s an abundance of article on this blog about that. Click here for our weight loss section. There’s also a video on my YouTube channel all about food swaps that shows you easy ways to lose weight. Click here. In my opinion the most sustainable way to achieve this through dietary change AND exercise.

Exercise also has many additional benefits beyond weight loss that I have not spoken about here. Your body is designed to move. It wants to move. It’s no coincidence that exercising releases the feel good hormones in your brain. That’s there to reinforce the behaviour as a good thing. So you’ll repeat it.

If your brain made you utterly depressed after exercise, it would be counterintuitive. From an evolutionary perspective, we needed exercise to survive.

Therefore, I’d encourage you to look out for activities you like to do and get going. It can be as simple as a walk and you can start slow and build up gradually.

The most important thing, is that you start.

Need more help

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