A question I get asked quite a lot; “how come I’ve put on weight since I started running?”

There are multiple answers to this.  I’ll start with the 1 over-riding simple solution, which you won’t like to read, and then I’ll give a few other answers and my reasoning for it.


You’re greedy.  You’re over eating.  You’re eating the wrong type of foods.  You’re welcome.

However, people don’t like to hear or be told this, and you’d be amazed (I am) at how many people tell me that they aren’t.  THEY ARE.  They can try to convince me until they’re red in the face if they like, but the simple facts are, that they are, and I don’t care!  I manage my own diet, they manage theirs.  I’m happy with mine, and they’ve asked my opinion on theirs, yet when I give the 1 simple answer, it’s the one thing that they won’t digest!!


Read it, take it on board and believe it.  They’re taking on more calories than they’re burning.  I’ll go into this below in my other answers.



When we run or train, we are conditioning our body to be better at it.  We hope that when we go out and do a 1-mile run, if we allow our body to recover and adapt to running that mile, then the next time that we run a mile, we will be a little bit more efficient at it.

That’s right isn’t it?  You want to be better at it?

Well whilst we’re doing this, and adapting to our training, we’re not only training our body to be faster at running that 1 mile, we’re also training our body to be more efficient whilst running that 1 mile.  We want to move more smoothly and fluidly.  We want to be more resilient to injury.  We also want to use less energy.  Imagine, that ultimately our goal in 6 months is to run a half marathon.  Imagine, that at this moment in time it ‘costs’ us, or we use 200 calories to run 1 mile.  That means that running 13 miles will ‘cost’ us at least 2600 calories.  If we could burn off those calories from our hips, we’d all be delighted, wouldn’t we?!!  But chances are, because we run it using our ANAEROBIC (mentioned below) system, we have to use energy drinks and gels to get the calories.  If we train effectively, then over weeks and months, we might be able to get the ‘cost’ of running each mile down to 100 calories rather than 200 calories.  This is because we have adapted to our training and are becoming efficient at running and not using lots of energy.

Where people go wrong, is to presume that they are burning x amount of calories per mile, or per hour, and it is wrong, because they have adapted to become more efficient endurance runners.


If you’re running to lose weight; you’re a fool.  Sorry! I love to be the bearer of bad news!

Eat less.  It’s that simple!


Imagine that for every mile that you run you burn off 100 calories.  You go out for a few drinks on Saturday night and promise yourself that you’ll ‘burn it off’ tomorrow morning.  The few drinks turn in to 6 drinks, and you have a takeaway too.  Then a few chocolates with your friend.  Because we all know that talking your friend into sharing with you immediately reduces the calories in each chocolate by 50%!!  All of a sudden, you’ve taken in an extra 2500 calories in 4 hours.

That’s fine.  I’m not telling anybody to move to a monastery and live on rice and water.  But unless you’re going to go out and run 25 miles with a hangover the next day, don’t be foolish enough to lie to yourself that you can ‘burn it off’.  You can burn it off, it’s completely possible, but chances are that you won’t.  And if you do go out and run that 25 miles to burn it off, will you need to take energy gels with you and scoff afterwards?  Making sense?

Go out and eat and drink by all means.  Just factor those 2500 calories in over the next week and eat 400 calories less over the next 7 days and you’re nearly back to where you were!  And go and run that 25 miles and burn off an extra 2500 calories!!  Bonus!  Just be honest to yourself!  And plan things in!

If you run to lose weight; you will not achieve it. 

If you run to improve at running; you will. 

If you eat less to lose weight; you will achieve that too.


To better understand this, a knowledge of energy sources and how our body uses them for exercise will be an advantage.  I will get around to writing a bit on energy sources, but for now I’ll try to explain as best I can;

When we do any type of activity, whether it be something simple like brushing our teeth, or something hard and intense like running a race, our body needs to get fuel from somewhere to power our muscles.  We can use oxygen from the air that we breathe, and we can use sugars from the stores in our muscles.

If we are using oxygen as the main source of energy when we’re running, then we can go for ever and ever at that intensity, until oxygen is no longer available.  This is called AEROBIC exercise, using our AEROBIC system.

If we use sugar in our muscles as a source of energy when we’re running, we can only run until the sugar supplies run out.  Then you ‘hit the wall’.  You can replace these sugars with energy gels or energy drinks, but you’ll probably not be able to replace the sugars quick enough!  We only have about an hour’s worth of these sugars stored in our body.  This is called ANAEROBIC exercise, using our ANAEROBIC system.

When we are running using our aerobic system, it’s at a low intensity, where we aren’t out of breath, aren’t puffing and panting, can have a conversation or at least say around 5 words of a sentence before having to take in a breath of air.

When we are running using our anaerobic system, it’s at a higher intensity, where we are out of breath, where we’re puffing and panting for air, and we can’t really hold a conversation.

Now here is the key.

A lot of beginners to running, work at the wrong intensity most of the time.  They’re running too hard, and are spending too much time in their ANAEROBIC zone.  They think that running is all about going hard.  They use up the body’s sugar supply rather than using oxygen to power the muscles.

And because of this; because their muscles are all out of sugar, they go home and raid the fridges and cupboards for anything that they can get.  They crave sugars; their body needs to replace the sugars.  The problem is, that they don’t just replace these sugars, they pig out and ram as much food, not just food, but crap food, in as they can as quickly as they can and ultimately, they put in more sugar than they burned during that run.


It can quite easily be managed, by;

Running in your aerobic zone a lot more.

Not having crap food in the house to scoff on after a run.

Replacing sugars slowly and gradually, not scoffing.


My fitness pal is a fantastic tool, to calculate the calories in the food that you eat, and to tell you the percentages of carbs, proteins and fats in each meal.

Some people use my fitness pal to manage their daily nutritional intake.  As long as you’re telling it the truth, it is a fantastic tool to help you to achieve whatever nutritional goal that you might have.

Some people also link up their My fitness pal profile to their Garmin watches and so when Garmin ‘tells’ my fitness pal that you’ve just done a 5-mile run and burned 750 calories, my fitness pal then adapts your daily calorie allowance and lets you have 750 extra calories to keep you on target.

The problem with this comes when you have become an efficient endurance runner, as mentioned above.  It might only ‘cost’ you 380 calories to run 5 miles, but Garmin & My fitness pal tell you that you’ve burned 750 calories.  You then eat an extra 750 calories and hey presto you eaten an extra 370 calories than you need. (750-380=370) and low and behold, you don’t lose any weight!

My advice, if this applies to you, is to use My fitness pal to monitor nutrition, but to disconnect Garmin from it so that it doesn’t factor in any exercise that you’ve done, and then doesn’t miscalculate anything.


The one single thing that can help you to lose weight, is to reduce your portion sizes.  Regardless of what it is you’re eating, reducing your portion size will reduce calorie intake, and will reduce your waist size.  You can work on other things like altering what you eat, but if there is only one thing that you change, reduce your portion sizes.

1 piece of chocolate won’t harm you.  1 bar of chocolate will.

1 small potato with your dinner won’t harm you.  3 big potatoes might.

Studies have shown, that by eating off smaller plates helps lead to weight loss.  A reduction from 12” dinner plate to 10” leads to 22% less calories.  Simple!  The centres of both of these plates are the same size, but naturally we would put more food onto the bigger plate.


People ‘carb load’ or ‘fuel’ for their runs.  People don’t need to most of the time!  We are usually training or running so that we can be better, more efficient, run further and faster and perform better on race day.

Going out for a 90-minute run?  Why in the world are you taking Lucozade with you?  You won’t die on a 90-minute run.  You don’t need to carb load, you don’t need to fuel, you don’t need anything.  Except maybe to reduce the intensity as explained above.  And maybe to allow your body to adapt to not having sugary food and drinks poured down your neck every 20 minutes!

And when it comes to the few times that carb loading is needed, it’s quite often not done right anyway!  If you think you’re right to ‘carb load’ at 6pm the night before a race, just so you can tell half of the world on Facebook, you’re wrong.  All that you’re doing is clogging yourself up and arriving on the start line of the race heavier than you need to be.  You won’t get any benefit from your ‘carb loading’ than if you didn’t do it at all!


Most people go to their running club, run 4 miles and then sit around, have a few drinks and a chat.  Absolutely perfectly fine to do, and I really recommend it, just pay attention to how much you’re eating and drinking.

My running club is directly opposite a fish and chip shop.  People have fish and chips after their 4-mile run.  From a general observation, I’d confidently say that the ones who do it are the ones that talk about wanting to lose weight.  The ones who don’t talk about it, don’t do it.  There’s a correlation!

The best exercise for weight loss is to exercise self-control and self-discipline!

RUN Smarter|RUN Easier|RUN Faster