Intermittent Fasting For Fat Loss

“You should get on that intermittent fasting, bro.”

intermittent fastingYes, fasting is all the rage at the moment so today we’ll take a look at the results of using intermittent fasting for fat loss.

Because if you’ve set foot in a gym in the last five years, chances are you’ve hear this phrase above at least once.

This principle is based upon the concept of eating during a short “feeding window” followed by a period of fasting.

But despite the fact that it has only become somewhat “trendy” in recent times, intermittent fasting is a time-tested fat loss principle which has been used by many bodybuilders for decades.

Check out this e-mail I received from website member Jennie – and while your at it,  become a member yourself – it’s free and it means I can answer your questions, too:

“Hey Russ, 

A friend of mine recently started intermittent fasting and they talk about it a lot. It’s something I’ve long been curious of, and some of the things I’m hearing make it sound too good to be true. Could you explain how it works?”

I sure can.

Video Overview:

intermittent fasting

Intermittent Fasting – The Good

Intermittent fasting is a proven fat loss principle.

Based around the concept of a relatively short “feeding window” followed by a longer period of fasting, there are various different time splits currently being used out there in the fitness world, and they are largely dependent on the individual.

You’ll find anything from a 14-10 split – that’s a 14 hour fasting period and a 10 hour feeding window – to a 16-8, to a 20-4.

I have found the 16-8 split returns optimal results, mainly because clients tend to find it easier to fit this approach into a busy lifestyle.

In my experience there are generally two types of individuals who reap the most rewards from IF:

  • Group 1 – some people naturally just take to intermittent fasting. They like the discipline and the structure it offers. If that’s you, then that’s great!
  • Group 2 – these are individuals who already have a pretty solid diet in place, but results have slowed down. IF can be used as a means to boost results again.

One of the most interesting things about intermittent fasting is that the fasting period is believed to increase the activity of genes responsible for how much fat the body is able to burn. Throughout the fast, these genes enable us to burn more calories and more body fat. (2, 3, 4)

Some researchers believe that when we finally eat at the end of our fasting period, the activity of these key genes is boosted even further for a short period of time. (1)

Further still, the relatively short window for food tends to reduce the urge to overeat.

You see, I’ve found that once the body has adapted to adhering to the fasting window – which usually takes a couple of days – it becomes very straightforward to avoid the temptation to snack on junk food, as we get used to the fact that we are not allowed to consume food outside of our designated feeding window.

Once the window opens, we are so busy trying to fill it with our daily calorie intake, that we don’t feel the need to overeat.

These are two more reasons why IF works so well for fat loss.

Interestingly, research also indicates that fasting is capable of increasing red blood cells and hemoglobin levels, meaning our muscles have a better supply of oxygen during activity.

This is essentially what endurance athletes are trying to achieve when they take illegal substances – more oxygen to the working muscles. Of course, fasting won’t create the same levels of increase as an illegal drug, but it has been shown to boost performance naturally. (5)

All of these factors combine to make intermittent fasting a proven method for those with a clear goal of losing body fat.

intermittent fasting

Intermittent Fasting – The Bad

No style of dieting is perfect, and intermittent fasting comes with it’s own set of drawbacks.

Most notably, if your goal in the gym is to gain muscle size and overall body mass, then IF is probably not the approach for you.

That’s because your diet is still responsible for how much size you gain.

Hitting your macronutrient targets on a fat loss diet is usually quite straightforward, as we are working with a calorie deficit.

However, these benefits don’t transfer well to a diet which is based around building muscle.

That’s because when we are following a plan based around gaining mass – such as my proven Supersize You diet, which is currently being used by thousands of you around the world to great resultstrying to consume a 500-1000 calorie surplus each day can become extremely problematic when we restrict ourselves to a relatively small feeding window.

Even if we achieve our macronutrient targets, we often leave ourselves feeling bloated and unhappy.

And while there are several key studies documenting the effectiveness of fasting for weight loss and body composition, the body of research is very scarce when it comes to using fasting as a means to gain lean muscle tissue.

So, while it certainly won’t create muscle loss, this is much more effective when used as a fat loss strategy and I encourage you to play it to it’s strengths for maximum results.

intermittent fasting

Another potential drawback of IF is meal timing.

While some folks will say it doesn’t matter what time you begin your feeding window,  it must be something that can fit your lifestyle.

This will make it far easier to stay disciplined.

To get the most out of intermittent fasting, I always recommend beginning your feeding window the moment you finish your weights workout.

This will produce maximum results.

However, those who train in the evening don’t have the luxury of this option.

Depending on your working hours and training times, you may occasionally find yourself hitting a workout towards the end of or even outside of your feeding window – i.e. if you have to train at 8 p.m. it would be foolish to schedule your feeding window from 9.30 p.m. to 5.30 a.m. as you’d be up all night!

So remember to be flexible.

intermittent fasting

You can even build your feeding window around when you personally have the biggest food cravings.

Trust me, there is no point trying to fast in the evening if you know this is the time of day you crave food the most.

In this situation it would probably benefit you more to flip the script a little.

The majority of people who use intermittent fasting go for this approach:

  • Morning fast
  • Mid-afternoon weights workout
  • Evening feeding window

But instead of rigidly trying to stick to something that doesn’t fit your lifestyle, you may find that a morning workout and evening feeding window would probably fit your lifestyle much easier.

If that’s the case, do it.

Because the best diet is the one you can stick to.

intermittent fasting

One more useful approach with any kind of fasting diet is to end your feeding window with some slow-digesting protein – think cottage cheese or casein – this will keep you feeling full throughout the early hours of your fasting period.

From experience, once you topple those first few hours of a fast, it’s a cinch to complete the rest.

As mentioned below, one of the trickiest things for most people when training in a fasted state is whether or not they should use a BCAA or other supplements while they workout.


intermittent fasting

Intermittent Fasting – The Myths

There are a ton of myths surrounding intermittent fasting.

  • Intermittent fasting is not a golden meal ticket.

Some people claim that the general rule of calories in vs calories out doesn’t apply when following intermittent fasting.

They imply that you can simply “go wild” with food and dismiss it under the false excuse of “I can eat whatever I want, because it’s between 3 p.m. and 8 p.m….”

We can not fool the body into accepting junk food as quality fuel.

Look, you don’t need me to tell you that 10,000 calories is still 10,000 calories no matter what time the clock says when you consume them.

We cannot “trick” the human body, the most complex machine any of us will ever operate – a machine so complex we are still discovering new things about it now, thousands of years into our existence – into believing binge eating is okay.

Needless to say, the individuals who try to follow this approach rarely see any sustainable fat loss, or any results at all.

intermittent fasting

  • All or nothing

Another myth surrounding IF is that you need to completely overhaul your lifestyle to accommodate this type of dieting.

It’s not true.

Instead of suddenly flipping your life upside down come Monday and trying to fast every day, I find that the best results are obtained from intermittent fasting when clients use this approach, erm, intermittently!

Try starting with one or two days per week and you’ll be able to assess your body’s response to it, without allowing for natural metabolic adaptation to occur. It’s a fantastic way to shock the body to new results.

bcaa before fasted cardio

  • The BCAA myth

Ifyou let anyone at your local gym know that you’ve started using intermittent fasting, I’ll give you about two weeks before you hear this myth:

“You need to drink BCAA’s throughout your fast, bro, to prevent muscle breakdown.”

Not only is this unnecessary, it actually defeats the point of IF.

Research does not support the idea that IF causes muscle loss anyway, plus consuming BCAA’s will technically break your fast, as the amino acids being consumed will combine to form protein, defeating the whole point of a fasting period. (1)

This myth goes hand-in-hand with the belief that you need to consume BCAA’s before you do fasted cardio.

Again, if you do this then you are not actually performing fasted cardio.

Click here to read more about this.

To keep it simple and effective, the only things you should use around your training when in a fasted state should be water, creatine and/or beta-alanine.

In fact, you’ll find  creatine and beta-alanine particularly useful when training in a fasted state as they will serve to increase your strength an endurance while you workout, but they do not contain amino acids which are converted into protein, meaning you are not breaking your fast.

Russ Howe pti


There are various approaches to dieting out there and you’ll get the best results by playing to your own strengths.

Intermittent fasting is proven and productive for fat loss, but it’s not for everyone.

I’d recommend starting by testing it out for a couple of days per week and seeing how your body responds to it – not just in terms of results – which are usually great – but also in terms of how you handle the fasting period and your cravings.

Always remember – the best diet is the one you can stick to.

You may prefer small frequent meals, three large meals, IIFYM, intermittent fasting, low carbohydrates, etc.

Once you have something which plays to your own strengths, stick with it!

For instance, there would be little point going on a low carb diet if you absolutely love carbs.

If you want to join the thousands using customized diet plans by me, they are available here.

intermittent fasting

Hopefully today’s article has helped to establish whether intermittent fasting is a method which would fit your lifestyle and, if so, best of luck with it.

Share it if you enjoyed it.

Be sure to jump on my free email list – bottom of article – for more training tips like this from me. If you need a new workout program to smash in the gym, you can access all of my full training programs here. They are also free.


1. Trabelsi, K., et al. “Effects of Ramadan fasting on biochemical and anthropometric parameters in physically active men.” Asian Journal of Sports Medicine 2(3):134-144, 2011.
2. Pilegaard, H., et al. “Effect of short-term fasting and refeeding on transcriptional regulation of metabolic genes in human skeletal muscle.” Diabetes 52:657-662, 2003.
3. Hildebrandt, “Exercise attenuates the fasting-induce transcriptional activation of metabolic genes in skeletal muscle.” Am J Physiol Metab 278:E1078-E1086, 2000.
4. Mattson, M. P. and Wan, R. “Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems.” J Nutr Biochem. 2005 Mar;16(3):129-37.
5. Stote, K. S., et al. “A controlled trial of reduced meal frequency without caloric restriction in healthy, normal-weight, middle-aged adults.” Am J Clin Nutr 85:981-988, 2007.

4 thoughts on “Intermittent Fasting For Fat Loss”

  1. Pingback: Russ Howe PTI
  2. Hi, I’m a Thai Boxer in my last 2 weeks weight cut with 3.8kg to go (and I’m already lean). I’ve been fasting for 12 hours (9pm-9am) then taking BCAA prior to my morning run. Would you recommend, that I stop taking the BCAAs until after my cardio?

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