Fact or Fiction: Fasted Exercise

OK, so today’s fact or fiction maybe more of a straight talking, opinionated/education mix but there is plenty of mystery in this area to discuss…

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“I HAVE to eat before I exercise, otherwise, where does the energy come from?”

to the other extreme,

“I never eat before exercise, I’d be sick if I did!” 

Is either one true? 

I think everyone reading this is quickly thinking how subjective an area this could be, but instead, let’s dig into some details, see where this rabbit hole takes us!

What is it?

So, to start off, Fasted exercise (FE) is simply exercising in a state of glycogen depletion. Generally achieved with no calories in 6hours+ prior to the workout session.

If you wanted to train for this particular “skill” or approach, fasted workouts are your bag!

In reality it probably has a place for any “self optimiser” looking to GET MORE, but not necessarily a staple, daily routine? Right?

Let’s break it down for some benefits & ways to to use FE to improve…

There are number of areas of research to call on here, and as always, at the bottom of the page is a list places to do YOUR OWN RESEARCH and reach your own conclusions. As Tim Ferriss often says on his famous Podcast, “Not a doctor, nor do I play one on the internet”

Instead, let us consider a few likely, real world examples and ways to use this to our advantage.

When are we typically in a fasted state? When we wake up.

When do we workout? Say, early, pre 8am or later in the day, 4-7pm.

Fasted state exercise in the pre 8am world of training (be it a 6am Crossfit Class or say a 5km run before work!) it is likely to expect this to be a FE session and probably very common.

Dependant on the intensity of the session, this maybe a great opportunity to see some of the additional benefits of FE…

A lower intensity workout can have the below added benefits…

·         Additional fat burn

·         Improved cognition

·         Increased growth hormone response & free testosterone

·         Increased endurance

·         Stability of gut

·         Hunger management & healthier food relationship

·         Anti-aging effects

Increasing the intensity broadly speaking reduces the benefits, by nature of the body’s reaction to the increased stress and inflammation from the training.  The body goes into a survival mode, this instead for example,, doesn’t increase fat loss, the opposite happens as the body is planning for the worst, keeping what it can for the worst still to come!

Another common raining time…

The evening or early evening Workout session… could be in a fasted state, but for most lunch was 12-1pm ish and so not necessarily in a fasted state for exercise (although dependant on metabolism and size of lunch could be possible.) 

So, what it likely benefits in this case?

Well the body’s natural Circadian rhythm is such that strength, testosterone, growth hormone and cognitive response to pain or fatigue is optimal for exercise in the late afternoon (genetically believed to be from the need for the kill towards the end of a day’s hunting before darkness for our ancestry).

Therefore, we would be well suited to an intense work out, in a Fed state (note meal timing and composition not discussed here) for optimal performance at this time.

A lower intensity work is of course no harm in this case given the circumstances and therefore just less applicable in this example.

Again, training goals have to be considered here…

 

So how do we Optimise our own training?

Rather than every option available, lets pick again these most common. If you have any further thoughts or questions comment below.

1.    Early workout, moderate to high intensity, with belief “I’ll be sick if I eat before a workout”.

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There are a number of ways to approach this. From a Fact or Fiction perspective, the workout is unlikely to make you sick if you allow 45 minutes, maybe 30 minimum after eating (small) prior to the workout.  Another point to note is you may need to fire your Circadian Rhythm faster than it would naturally. Light, Caffeine and Movement help here. So Warm up, in a bright space and then notice how your body reacts the improved process.

 

2.    Hungry or lethargic pre-workout, late in the afternoon (i.e. I couldn’t workout without eating) 

Fasted state or not, the hunger is not an issue during a workout 99% of the time, given “normal” eating times and common routines. This is an interesting part of Fasted exercise’s potential benefits as it assists with the psychological aspects clearest.  You are probably in the habit of eating at this time, like we are in the habit of sweet desserts, after dinner with the evening meal.  No one has died from missing a meal, nor do you lose muscle mass. In fact, experience shows it often enhances the relationship with food to more Food for Fuel approach.  Dehydration maybe a factor however, but cannot be reconciled at the time late stage. Drink more during the course of the day if this is a common feeling for you.

To Summarise

There are many ways to discuss this subject and weapons in our armouries to get over the common issues in workout timing and nutritional intake, ultimately, we are looking for progress, performance increase and self-optimisation.  So, we want to do what works best for this goal.

Understand the belief system maybe the things stopping you optimise right now, not your schedule or otherwise.  If you believe food will make you sick and eat your normal breakfast pre workout one day “to see what will happen” it will go wrong. You believe it, so it will come to you (maybe); or worse, stay in fear of it happening, never try to adjust, even some fat, small easily digested protein you’re not giving yourself a fair chance at seeing timely progress.

And a final word of warning, Post workout. Fasted exercise or Fed, it’s optimal to eat post workout.  But do not overeat or eat poor quality food.  The body and mind are in a state of increased nutrient absorption. Give it what it wants! Sure (Zn Mag) but overdo it and you feeding the relationship to foo rather than the body.  This can be a larger meal, but if you full up at the end or stuffed, you’re simply giving the body another job to do along with the fatigue recovery it’s handling!


Resources

https://leangains.com/fasted-training-for-superior-insulin-sensitivity-and-nutrient-partitioning/

https://leangains.com/fasted-training-boosts-endurance-and-muscle-glycogen/

https://fitness.mercola.com/sites/fitness/archive/2012/05/04/fasting-effects-on-human-growth-hormone.aspx

http://www.mercolafastdiet.com/blog/top-breakfast-myths.aspx


 
 
Luke Backhouse