The short answer is maybe, but less food means less energy which often means less movement... and fasting for a bit and then eating too much doesn’t work either, so it needs to be done right….
Let's look at Intermittent Fasting (IF) and how to add it into your life so that it supports, rather than hinders, your weight or fitness goals.
Most of the time, when people talk about fasting, they are referring to windowed eating or Intermittent Fasting (IF). This means you only consume food in an 8 / 6 / 4-hour window, and fast (zero calories) for the remainder of the day.
Other versions of IF include the 5:2 method and the use of an occasional 24-48 water fast.
The 5:2 method involves eating maintenance calories (around 2,500 depending on you) for 5 days a week and then dropping to a hefty calorie deficit (around 500 calories or one good meal) for 2 days a week. Lots of research has been done on this with great results, but you can't get away from the strict calorie-controlled nature of the approach.
Water fasts do exactly what they say on the tin and involve consuming nothing but water for 24-48 hours straight and a large amount of discipline. 😉
But as I always say, when people ask me what's the best diet out there is. It depends on what the goal is and finding one that you can stick to.
So, let's start with: What's the goal?
I think it's fair to say that most people want to lose a few pounds of fat and feel a bit healthier.
- We all know the first rule of fat loss…Consistent Calorie Deficit
- And the second rule of fat loss? Consistent Calorie Deficit
(and by consistent we mean weeks, not hours)
So, in theory, not eating for an extended period of time would definitely help with the calorie deficit? Correct.
However, is it possible to eat yourself out of calorie deficit and into a calorie surplus even within an 8 hour window? Also correct.
I'll leave those two facts there.
What else do we know about fasting?
Studies have shown that people who skip breakfast are actually more likely to be bit more sedentary throughout the morning.
Since we know that a good chunk of calories burned in a day contains those burned in NEAT (non-exercise-activity-thermogenesis) aka, walking around, getting chores done, taking the stairs etc, this fact could be of interest to those trying to lose weight. So ironically, by skipping breakfast to help us lose weight, we get a bit lazier and burn fewer calories as a result.
Say what now?
I'm sure you've heard the fact that your body will have replaced every single cell within it every 8 years. Well, this is autophagy, regeneration at a cellular level.
Scientists found that mice showed higher biochemical markers of autophagy in a fasted state than those in a fed state.
This is great, but autophagy occurs anyway; otherwise, our bodies would get very run down. We also know that autophagy occurs at the same rate whilst in a consistent calorie deficit as it does when in a fasted state. So, you don't HAVE to fast, you just have to eat less. And autophagy isn't magic, it won't cure disease or reverse the ravages of ageing any more than a healthy diet, some good exercise and a moderate calorie deficit will.
I'll have to break this into two sections: training and performance.
Is it okay to train fasted? Of course! You won't perform your absolute best, but you may enhance your body's ability to process fat at higher intensities which is a good thing, but I'd be willing to bet that a fully fed You would beat a fasted You in a 5km race if the only difference was your recent food consumption
In the sports world, this approach is known as train low, compete high. The low and high they refer to here are the amount of carbs an athlete eats over the day, but I don't think it's too much of an extrapolation to apply it to food in general for the layman.
Aka Muscle Growth
We know is that it's easier to add some muscle if you're in a calorie surplus. Training hard and convincing the body that the best thing to do is grow bigger muscles as a result could always do with a bit more fuel. But remember, this is opposed to our first two rules of fat loss, so make sure you've chosen the right goal for you and work towards it consistently for a specified period of time, e.g. 12 weeks.
Some things fasting is really good for
It reminds you what it feels like to be truly hungry. Not just peckish... Not just fancying some chocolate… Actually running on empty and dealing with it.
Humans can survive without food for 30 days, but these days it sometimes feels like 30 minutes is a big ask, so fasting does help with that.
If you're a disciplined person deep down but are prone to snacking, then having set windows where you don't eat at all can really help with adherence to your food plan and calorie goal, so fasting can be used to help in that respect.
Earlier on, I mentioned that the best diet is the one you can stick to.
If your goal is to lose weight, you must be in a consistent calorie deficit – consuming less calories than you use for an extended period of time.
If one of the fasting approaches helps you stick to this, then go for it.
The problem with current trends in the weight loss world is that people tend to see everything as a quick fix, and then they can go back to 'the old ways'. Unfortunately, if you want to keep the weight off, that will never be the case. That's why it's worth asking yourself, "can I do this forever?".
If the answer's yes, you've found The One.
At Encore, we prefer to consider nutrition alongside our evidence-based training methods, giving your body 360 degree approach to improving your health and hitting your goals.
This means that the calorie deficit you create with your preferred nutritional approach is enhanced by the strength and conditioning sessions here, meaning you retain muscle, lose body fat, and become stronger and fitter in the process.
The other undeniable fact about fitness done well is that people naturally start to improve their eating habits. So, not only are you working out and converting fat into muscle, but the calories you consume almost always decrease and improve in quality.
If you want to put it to the test check out https://encorefitness.co.uk/30daytrial/ for details of our 30 day trial.