- - How to Safely Fast as a Cyclist

How to Safely Fast as a Cyclist


article by Barry Murray of A1 Coaching

In general, it’s good to give the body a break from anything. It’s good to take a break from exercise and not train every day. It’s good to not work all the time and to play instead. It’s even good to not think all the time to help clear the mind. The same applies to eating; it’s good NOT to eat all the time. However, modern day living has turned us into continuous eating machines. We do not have to hunt for our food any more. We do not have to grow our own food or even prepare our own food anymore. Now all we have to do is dial the local Thai or go to the drive-thru or walk into a restaurant. Even if we don’t do these things, all we have to do to get food is open the fridge or cupboard and turn on the oven or microwave. We are constantly surrounded by food and accessing it is very easy. On top of all that, modern food processing has made food cheap, tasty and palatable. So not only do we have easy access to food but modern day foods actually make us eat more often and more of it.

However, this is not how our metabolism is designed to function and it is not how we evolved. Studies of our pre agriculture ancestors show that they used to mainly eat only once per day, usually after hunting and foraging for food during the day. The conventional wisdom that we need to eat constantly throughout the day eating 3 main meals with several snacks is completely contrary to this. And when you look at the science behind how the body’s metabolism works and how it is has coping mechanisms to deal with food scarcity, you begin to realise how we are told to eat today goes against our evolutionary biology.

So we are designed to go for long periods without food and we do not waste away if we go a few hours without eating. In fact the research shows that muscle degradation does not occur up to 48hrs of fasting and blood glucose levels can easily be maintained for days without eating. More importantly perhaps is that several studies have shown how fasting can improve several health markers as follows:


Not putting the body in the “fed” state, switches off certain hormones. One such hormone is IGF-1 which is involved with cell proliferation. Too much of this can lead to many age related diseases such as cancer and diabetes. Less of it therefore increases life span and “fasting” periods lowers its production. Put simply, not giving the body too much work to do means it doesn’t wear out as quickly.

Increase fat burning

Two important hormonal switches occur when the body does not receive food. The first is that insulin levels remain low. High levels of insulin (which are released after eating carbohydrates and some proteins) block the fat burning process. In addition, studies on both men and women show that growth hormone (GH) is released during fasting periods. GH is known to switch on fat burning. So with low levels of insulin and high levels of GH, your body is more primed to burn fat.


With no food to digest or metabolize, the body can go into repair mode on a cellular level. This is called Autophagy which describes how the cells break down and recycles waste material. This improves the overall cell function and clears up the debris which is linked to aging.

Who does it work for ?

In order for these mechanisms to work, you first have to be in a position to fast. It is important to state this up front. If you are obese, unfit or stressed then going for long periods without food is potentially harmful. Like everything to do with health and fitness, the advice needs to be based on the individual. Another important aspect that governs your ability to fast is how fat adapted you are. This controls your appetite and controls your energy levels as your body can produce all the energy it needs from fat sources. If you constantly rely on carbohydrates to give you energy, then fasting is difficult. Fasting has also been shown to suit men rather than women as long periods of not eating can detrimentally affect female hormonal balance.

How to do it

Assuming that you are relatively fit, healthy and fat adapted, then fasting can be done in several ways. One of the easiest ways is to skip breakfast. This will give your body a 14-16hr window of not being in the “fed” state where all of the above benefits can kick in. Another example which many religions follow is a 24hr fast, or simply not eating from one meal to the same meal at the same time the next day. For instance, eating dinner one night at 7pm and waiting to eat again until the next day at 7pm. The important thing to consider is that this should not be a strict policy or not something that is forced upon you. If you don’t feel hungry in the morning, then simply wait until lunch to eat. That’s your fasting done. Or if you are travelling and don’t want to eat convenience food, simply skip a couple of meals and wait until you get to your destination. Living healthily is not about forcing yourself to be healthy; it should be done because it feels right and makes you feel good.

There is definite science behind fasting and simply not eating as regularly as you are told to eat, can improve your health. Fat burning improves, your cells repair themselves and you live longer. No brainer!


Barry Murray is a Performance Nutritionist with a BSc in Chemistry from University College Dublin and an MSc in Sports & Exercise Nutrition from Loughborough University. Barry specializes in endurance sports and has been consultant to professional cyclists for several years. He was worked with the BMC Pro Cycling Team and Orica-BikeExchange team as well as working as private consultant to many individual professional riders, triathletes and runners. Barry has been columnist for the Irish Independent newspaper, has featured on several national radio broadcasts and has presented seminars to various sports teams and corporate businesses. Barry’s uses a modern approach to nutrition for optimizing both health and performance. He has developed his own system over several years of his own research and practice that improves endurance, power/weight, recovery while also improving the individual’s overall health. This works for any level of athlete from beginner to professional. In fact, he finds those who are just looking to get fitter and improve their health make the most gains. Barry is also a competitive endurance athlete himself and races in ultramarathon events. He races competitively in ultra mountain marathon events and represented his country at the 2011 World Ultra Trail Championships. He has won several ultra trail marathons as well as many top placings in some of the toughest ultra marathons in Europe.


A1 Coaching

Leave a reply
Share on