Weight loss and exercise
So many people talk about weight loss and exercise as if they are one and the same thing, when in actual fact exercise gets you fit and getting your energy balance right manages your weight.
When members come to get weighed, and they haven’t lost the weight they expect to, the first words from their lips are ‘I’ve done loads of exercise this week, I can’t understand why I haven’t lost weight.’ Well our view is usually, the reason why you haven’t lost weight is because you haven’t tracked your calories, regardless of the amount of exercise undertaken.
There are of course lots of benefits to exercise, improvements in heart and lung function, circulation, improvements to your strength and muscle tone, changes in shape, improvements to your mental health and lastly maintenance of weight. Note that says ‘maintenance’ and not weight loss. This is because to lose weight, we need to get a calorie deficit, and it’s difficult to get the correct level of deficit with exercise alone.
What is a calorie deficit?
First of all we need to understand that all calories are, are a unit of measurement. Much like we measure length in feet and inches or centimetres and millimetres (depending on how old you are), energy can be measured in kilojoules or kilocalories, calories for short.
A calorie deficit is where we consume less calories than our body needs to perform all of its metabolic functions, from breathing, to cell regeneration, to nerve stimulation, to digestion, to walking, running and exercising. The more we move, the more calories we burn. BUT!!! We need to get into that deficit for that to translate to weight loss.
If you eat the same calories across the week or month as your body needs to perform all of it’s functions; across the week or month your weight will stay the same. If you eat more calories than it needs to do all this, then the body being very clever, takes that energy that is initially stored in your liver and muscles as glycogen, then if the liver and muscles don’t use it, usually after about 48 hours, it is taken out of the liver and muscles and converted into fat stored under our skin and around our organs. It stores it this way, because it can then use that fat (or burn it) when we don’t put enough energy in, convert it back to energy to fuel for our muscles and ensure our bodies function the way they should. So when we lose weight, if we have stores of fat, that is what we lose.
The average person requires a calorie deficit of around 500-600 calories each day, from what their body needs to function, in order to lose 1-2lbs a week. Now this number isn’t just plucked out of the air. This number comes from the fact that 1lb of fat, is worth 3500 calories. So 3500 calories divided by 7 days is 500 calories a day.
The weight loss may vary depending on other things like how hydrated you are, or how often you go to the toilet, but generally speaking, the 500-600 calorie a day deficit will mean we lose 1-2lbs of fat from our bodies each week.
A note about keto diets or high protein/low carb diets
Keto or high protein/low carb diets are very popular because they get a dramatic weight loss usually early on in the program. The reason for this is because when you stop eating carbohydrates, your body at first uses the reserves of energy in the muscles. Depending on your height and muscle mass, when your muscles deplete of this energy, stored as glycogen within the muscle tissues you can see a weight loss of around 7lbs or maybe more if you have quite a lot of muscle tissue. So when we weigh after a week on a keto diet (which will still give you a calorie deficit) we may see that we have lost around 8lbs in weight. But we have only probably lost 1lb of fat (because of the calorie deficit) and 7lbs in glycogen. When we put carbs back in our diet again, the muscles fill back up, and we will gain that 7lbs on the scales again.
Continuing with the keto diet will result in fat loss, but it will slow down after that first week. This works because your body isn’t getting any carbohydrate in from foods, so it has no choice but to burn fat from your body’s stores to get energy to perform it’s functions. This is obviously quite appealing for those of us who want to lose fat, but there is a big downside to having a low carbohydrate diet, especially if we like to exercise. Carbohydrates are our bodies most efficient source of energy. When we eat carbohydrate our muscles utilise the readily available energy to fire, and allow us to perform our activities efficiently. Carbohydrates are also the best source of energy for our brains. By having energy readily available it allows us to think clearly and have good cognitive function. So, when we remove carbohydrates from our diet, we can end up feeling very lethargic and experience brain fog. If you have ever tried to exercise when you are depleted of carbohydrates it can make you feel like you are made of lead, and is not a nice feeling at all, and can really hinder your performance.
So, because we recommend and encourage lots of physical activity at Be Strong, for all the benefits it brings, we most definitely encourage you to continue eating carbohydrates.
So why can’t I get my deficit through exercise?
Getting back to this calorie deficit. If we are currently eating to the point that we are gaining weight, we are possibly eating around 3-4000 calories a day. And this is potentially in the realms of 1-2000 calories more than we actually need. So, to get into the realms of the 500-600 calorie deficit, we may need to burn an additional 2000 calories a day, which is just insane to even attempt that through exercise.
Even if we are eating to the point that we aren’t getting any bigger, we are simply maintaining, we still need to burn 500-600 calories a day in exercise.
And I am very sad to say that unfortunately exercise doesn’t burn anywhere near as much as we think. Our calorie burn depends on a lot of things including gender, muscle mass and overall mass, but we have included below, calories burned by the average female for a few popular activities.
- 25 minute HIIT sessions burns in the region of 220- 250 calories.
- A 5 mile run burns approximately 500 calories
- 1 hour swimming breast stroke burns approximately 400 calories
- 1 hour walk burns approximately 300 calories.
Can you see now, how hard it would be to maintain the level of exercise to get your deficit?
We have also done a few calculations to work out how much you would need to exercise if you were currently gaining weight (slowly) but wanted to keep eating the way you are eating. If you are currently gaining a pound a week and want to change that to losing a pound a week, you would need to do an activity that burns about 1000 calories, every single day, so you could still eat that same amount of food.
You could choose:
- 10 mile run
- 1 hour 10 minutes spin class
- 1 hour 30 minutes swimming
- 90 minutes circuit training
- 2 hours HIIT
- 4 hours strength training/lifting heavy weights
- 3 hours low impact aerobics
- 2 hours boogie bounce/trampoline fitness
- 2 hours vigorous dancing
- 4.5 hours mid tempo dancing
- 5.5 hours yoga
- 3 hours pilates
Still want to exercise your way to weight loss?
Eating because we have earned it!
Another reason we don’t always lose weight when we have exercised loads, is because we use that exercise as a reason to fill our boots with snacks, treats and bigger portions, after the event. We all do it! But as you can see from the examples above, that 220 calorie HIIT session just about burns off a couple of pieces of toast, never mind a piece of cake or fish and chips. So this is why we ask you to treat exercise and weight loss separately.
We absolutely want you to do both because there is no doubt that physical activity and exercise improves our physical and mental health in so many ways, however, look at food intake for weight loss, and exercise for improving fitness. Keep the two separate and you are on to a winner. When this penny drops with people, it is like a light bulb and when we really start to see the magic happen.
Can’t I convert fat to muscle?
When we exercise we often hear that people think they are converting fat to muscle. Just so you know, that is a physical impossibility. Fat is burnt and muscle is built. It does not turn from one thing into another. They are two completely different metabolic processes and are made from different tissues and chemical elements. We burn fat by getting our calorie deficit and we build muscle by putting those muscles under strain, causing little micro tears which repair and make themselves bigger and therefore stronger.
There is a benefit to having more muscle though – the more muscle we have, the more efficient we are at burning calories, so it is definitely worth including some strength training and load bearing workouts in your regime, because we will increase the amount of calories our body needs to function and perform, therefore making it easier to get a calorie deficit.
Where does the fat go then?
We couldn’t finish this article without completing the circle and passing on the knowledge of where fat goes when we lose it. If you have done the Reset Restart course, you may well know the answer to this.
Scientists from the University of New South Wales posed this simple question to 150 health professionals: When somebody loses weight, where does the fat go? And, incredibly, of the 150 doctors, dietitians, and personal trainers they surveyed, only three out of 150 respondents (that’s 2%) answered the question correctly.
Some of the misconceived answers were:
“Fat is converted to energy”
“Fat was converted into muscle”
Or that “it leaves the body through the colon”
Around 25% didn’t have a clue.
But what actually happens to fat in our bodies as we lose it is a series of complex metabolic processes. When the body goes into calorie deficit, it needs to break the fat cells down to release energy for our body to function and move. But the whole fat cell isn’t converted into energy, it is broken back down into its individual molecules and then the energy is released back into the muscles, and the rest has to go somewhere else.
The scientists at the University of New South Wales went on to do some very complex calculations, and they published a report in the British Medical Journal but ultimately found that when we lose fat, our cells use the released energy, but then there is a lot of waste molecules, which need to leave the body.
They leave the body through two main ways. The first and largest percentage (84%) is through our lungs, excreted as Carbon Dioxide and the rest (16%) is excreted as water through urine (mainly), sweat, breath, tears and other bodily fluids. The scientists wrote in their article “If you lose 10kg of fat, precisely 8.4kg comes out through your lungs and the remaining 1.6kg turns into water. In other words, nearly all the weight we lose is exhaled.”
We just want you to really digest what this article is saying. Exercise for fitness and calorie deficit through food for weight loss. Get it right, and the magic will truly start to happen for you.