There are always 101 invisible things that contribute to any top-quality sporting performance.

There is a great deal that we have changed with William’s training for ultra-distance racing as the years have gone by (recently this has included introducing maximum level loaded walking with William carrying roughly his own bodyweight for 15 mins at a time, weighted step training, advanced breathing exercises originating from the martial art of Stav, depth drops to improve his plyometric ability, drag training on a treadmill, supersets of partial range deadlifts and squats, all while running a low weekly mileage – just to name a small few).

As William gets older his training gets tougher – and so does he. At a time of life (William is now 59) when most people are starting to think that getting up off the sofa is a bit like hard training, William isn’t content to try to maintain his current performance levels. He is still always looking to improve – and then to keep improving. Obviously that’s the only way one can set a PB or break a record – you don’t get better by doing less work than you’ve done before!

One thing that has changed considerably for this race is William’s in-race nutrition.

This is the first multi-day race William has attempted while on an extremely low carbohydrate diet.

Low-carb diets are becoming increasingly popular for both overall health and sporting purposes but they still tend to raise a few eyebrows among the general public, most of whom have for many years been bombarded with the message that fats are bad for you and that carbohydrate is essential in a normal diet – and doubly so for an athlete.

It is quite commonly recommended that a runner should consume around 60gms of carbohydrate per hour (generally as simple sugars) when running.

In practical terms, in an effectively non-stop ultra-distance event of this kind that would add up to around 1440gms daily – nearly 1.5kg or about 1 and a half bags of sugar – and that is per 24hrs of running.

As this is an 8 day race, were William to have followed this kind of advice he’d have been trying to consume the equivalent or nearly 12kgs / 26.4 lbs of sugar during the event!

In reality William has never been able to consume any where near this amount of carbohydrate (doing so for an hour or two is no problem, but William cannot sustain that sort of carbohydrate intake indefinitely as it causes him gastro-intestinal problems).

Instead, William has been taking no added carbohydrate whatsoever during the entire race; the only carbs he’s been having have come in the form of a (relatively small) amount of lactose in the milk he has been drinking (lactose is naturally occurring milk-sugar), plus a fairly minimal amount from vegetables with his meals.

William has been taking a moderate – not high – amount of protein, but most of his energy has been coming from fats.

Healthy fats – and lots of them – from both natural foods including eggs, cheese, mayonnaise, olive oil, butter, cream, coconut oil etc, and as a medium chain triglyceride oil supplement (which being in liquid form is easier for him to take in a drink).

William has been “fat adapted” for a long time (partly because as he cannot consume huge amounts of carbohydrate over long periods, he has trained himself to run using his bodyfat as his major fuel source).

However, over the last couple of months he has taken this a stage further by virtually cutting out carbohydrate from his diet altogether and consuming less than 50gms of carbs per day (in simple terms that is equivalent to about 2 slices of wholemeal bread).

One of the big advantages to using dietary fat rather than dietary carbohydrate as a main fuel source during an ultra-endurance event of this kind is that gram for gram, fat has around twice as many calories as carbohydrate. Which in turn means that William can eat the same sized meal or drink the same amount of fluid, but gain twice the number of calories per portion.

Has this worked? While there will be much that we will learn from his 8-day race experience and undoubtedly much that we can improve upon for his next race, the short answer is clearly a big “yes”.

Quite obviously managing to run over 1000 kms in less than 8 days while consuming remarkably little carbohydrate is pretty clear proof that fats can fuel even the most arduous of sporting performances…

Shaun Brassfield-Thorpe – www.ULTRAfitnessTraining.com