Your questions: Preparing for half marathon. Training intensities and nutrition.


What is the difference between preparing for marathon and half marathon?

In reponse to questions about how to prepare for marathon – specifically how fast should the long runs be and what should I eat, my response was to learn to burn fat for fuel to avoid hittibg the wall (sugar crash) and to do most training at an easy conversational pace to develop the aerobic system.

So then another client asked how half marathon preparation should differ. Well, the short answer is not much. The longest run need really be no longer than 15-16 miles maximum but shiuld still be mostly focused on easy aerobic running, given that it’s still around 98% aerobic and only 2% anaerobic (without oxygen).

If, however, you already have a very well developed aerobic base, there’s nothing wrong in throwing in a little bit of faster than race pace training, perhaps once a week, as you get closer to race day. You might also schedule in the odd 5k or 10k race as part of your build up. But ensure good recovery from these with lots of easy paced running or rest. So it’s similar to marathon but with a little more leeway for speed work.

As far as nutrition is concerned, proper fuelling is proper fuelling, whatever the distance. What is good for health is good for performance and good for weight management too. The healthy diet is based on real whole foods, whether plant or animal. Eat what we are adapted to eat. There is no perfect diet – only what are adapted to and what is not going to create a defensive inflammatory response in our bodies.

So processed foods of all kinds should be minimised or ideally eliminated. The main culprits for inflammation, apart from the obviously processed products, are so-called ‘healthy whole grains’ and dairy products. Modern grains are nothing like those of even a hundred years ago and drinking the milk of another animal is probably not we are adapted for if you think about it. I believe it takes something like a minimum of 40,000 years for us to adapt and we’ve been eating grains for around 10,000. It’s not just coeliacs that need to worry about this in my opinion – but that’s a big topic in itself.

Eat plenty of natural healthy fats instead, including saturated fats. Drink water, tea, coffee, but not fruit juices. Stable blood sugar and therefore a steady supply of energy is what we’re looking to achieve, instead of constant spikes and dips. You will only be inclined to eat when really hungry (which is very rare) and it’s easy to train fasted for extra benefits – you can really get into some serious fat burning by doing long runs fasted at an easy pace, but ONLY IF YOU ARE ALREADY ADAPTED – otherwise you will feel terrible.

There are those who will argue that you need carbohydrates to fuel high intensity workouts. Again, this is only true IF YOU NORMALLY RELY ON SUGAR TO FUEL THESE EFFORTS. Once adapted to fat burning you can do high intensity fasted for added benefits – more human growth hormone (yes, you can build muscle without food because it’s exercise that primarily causes muscle growth, unless you are severely malnourished of course), more speed and power and a higher metabolic rate. I know all this flies directly in the face of what you have been told by sports drinks and supplements companies with their bogus biased ‘research’. However, I and many others who have done this know this to be true.

How long does it take to become fat adapted? Usually between 1-3 weeks if you go cold turkey. This can be very unpleasant, especially if heavily addicted to carbohydrates. You will feel weak and lacking in energy. This is just your body recalibrating to use fat for fuel – a far cleaner and much less damaging source of energy. Anything sweet that you eat during this period, including artificial sweeteners and fruit, can make it harder. You need to be incredibly strong wiled to do it this way and most will not last long.

Personally, I took a more gradual approach over the course of around 6 months to a year I suppose – by then a different way of eating had become ingrained. I was more energetic, much lighter, same muscle mass as before, but much lower body fat. I rarely feel genuinely hungry now and will usually only have one or two meals per day with snacking a rarity.  I do indulge occasionally but it is now very easy just to get back to it again immediately because eating this way is now habitual and I’ve seen and felt the benefits in myself and clients. Anybody can come and talk to me to learn more about how to achieve this.

Do you need to go zero carb to get these benefits? Absolutely not – many populations around the world have thrived on a diet of natural starchy carbohydrates, but none has failed to get sick on the Western diet of processed carbohydrates. Instead of worrying about macronutrients, it’s better to just think about eating real whole food, especially initially. Avoid anything with more than a couple of ingredients listed. The diet in practice will be based around the following: fish and meat, eggs, nuts, seeds, fruit and vegetables, legumes etc. Include plenty of natural fats and avoid grains. For me, the jury is still out on dairy but it can easily be replaced by coconut, other nut and soya options for safety.

Inevitably the nutrition side has taken longer to address than the running side because it’s a complex subject and we have been so bombarded by marketing messages that we often can’t see the woods from the trees, so just try to keep it as simple as possible.

For more information, contact David on 07504439555 or email me at

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s