LCHF (Low Carb High Fat) – The Fat Adapted Approach to Sports Performance. Do any of the Elite athletes use it? Simple answer is YES! The harder question is who uses it and how? Being fat adapted is slowly becoming regarded as a competitive advantage especially in marathons, ultra marathons, Ironman and other endurance type events. The science behind athletic performance and fat adaption is still trying to catch up to the Elites but the data is slowly emerging.

In an article written by Peter Defty titled – The Emerging Science of Fat Adaption he writes about some of the findings from the FASTER Study (FASTER=Fat-Adapted-Substrate oxidation in-Trained-Elite-Runners) The Study conducted by Dr. Jeff Volek RD/PhD, his graduate students and colleagues, looked at two groups of elite male ultra-marathon runners – one following a conventional high carbohydrate diet and the other a low carbohydrate/fat-adapted strategy and compared the physiological differences between them.

Wisconsin’s Zach Bitter – The American record holder for running 100 miles and new world record holder for the most distance run in 12 hours 101.66 miles, was one of the participants of the FASTER study. In his blog he wrote about some of the personal results he was able to take from the study.

zach-bitterOver the last few years LCHF has gained some real momentum in the areas of weight loss, management of type 1 and type 2 diabetes, plus many other areas of public health. The approach however in the area of public health is very different to that of LCHF – Fat adaption and performance. The principles are the same, the application of these principles is not. People often get caught up with LOW CARBOHYDRATE and take it to mean no carbohydrates. What is very clear reading through some of the blogs of these Elite Athletes is they still have carbohydrates. LCHF – Fat Adaption is a training tool for them, to develop a greater ability to be fueled by fat. Their goal is to become what is often referred to as Fat Adapted, they use Carbohydrates strategically in training and racing. The Carbohydrates become their natural performance enhancers.

Nutritional Ketosis and Fat adaption what is the difference?

In simple terms:

Nutritional Ketosis – When your body uses its fat stores predominantly for energy. Involves a greater restriction on carbohydrate intake and for some people this could even be as low as 20gms per day.

Fat Adapted – Your body is considered to be metabolically flexible enough to be able to switch between using fat and glucose for energy with little or no drop in Performance. Fat adaption involves periodic Nutritional Ketosis and Carbohydrates are used strategically throughout training and racing to enhance performance.

So who is doing it and how?

Firstly I must thank Peter Defty -General Manager at Vespa, Optimized Fat metabolism (OFM) at this point for his assistance in compiling this list. It is by no means a complete list, there are athletes and sporting teams that are rumored to be using LCHF strategies to improve performance but are not publicly making it known one example of this could be Novak Djokovic.

Zach Bitter – 100 mile American record holder and the world record holder for most the distance run in 12 hours.

Jon Olsen – previous 100 mile American record holder & 2013 – 24 hour World Champ

Dan Lenz – in 2015 2nd at Umstead 100 miler

Jenny Capel – Winner of San Diego 100 and 4th Overall

Nikki Kimball

Nikki Kimball – in 2014 Ran the Marathon Des Sables for the first time and won

Roxanne Woodhouse – at 52 years old won the Zion 100 by almost an hour ahead of Susan Bron a high carb athlete

Mike Morton – in 2013 won both Rocky Raccoon and Iron horse 100 within a week of each other

Sami Inkinen – Ironman 70.3. (half-distance) World Championships 2011, Age Group World Champion

Jean Pommier – at age 51 2nd Overall in the Ruth Anderson 50 miler

Calum Neff – 2nd at FLS Sugarland 30k a day after winning the Brazos Bend Trail Half Marathon.

Jeremy Humphrey – winner of River of No Return Endurance runs 100km

Bevan Mckinnon – in 2014 won the overall age group race at New Zealand Ironman

Tim Reed – in 2015 Ironman 70.3 Auckland- Asia Pacific Championships- 1st Place (Fastest run)

Tim Olsen – winner of the 2012 & 2013 Western States 100 mile

The LA Lakers

Members of the Australian Cricket team

Players in both Melbourne and Port Adelaide football clubs

So how do the Elite Sportsmen and Woman use LCHF- Fat Adaption?

A phrase you often hear in LCHF conversations in regards to sporting endeavours is Train Low Race High, I think this sums it up nicely. Zach Bitter and Sami Inkinen are possibly two of the most vocal elite sportsmana round LCHF. Zach Bitter discusses in his blogs and podcasts how a state of Ketosis assists him with recovery and he has a big emphasis on strategic carbohydrates during intense training blocks and in racing. The following is a series of links to some of the above Athletes pages and blogs and in their own words how they use a low carbohydrate approach to win races and break world records and train. For others it outlines some of their decisions for making the switch to the Low Carbohydrate approach.

Zach Bitter – ‘Lots and Lots of Saturated Fat’, ‘Gauging Recovery and Strategeizing Pre Race Nutrition’, ‘How Zach Bitter Ran 100 Miles in Less Than 12 Hours’

Sami Inkinen – ‘Becoming a Bonk Proof Athlete: Fat Chance!?’

Mike Morton – ‘Fuel’ (Requote from

Calum Neff – ‘Changing Fuel Tanks’

Nikki Kimball – ‘Marathon Des Sables 2015’

Bevan Mckinnon – ‘How to win the Ironman on LCHF’

Tim Reed – ‘The Low Down On His Low Carb Diet’

Tim Olsen – ‘Nutrition’


Jenny Capel – ‘Brief Summary of Reasons for Changing to a LCHF Strategy’

Roxanne Woodhouse – ‘Conventional Carbohydrate-centric approach wasn’t working’

Jean Pommier – ‘Vespa Testimonial’

In closing I think Zach Bitter sums it up best.

“When I start reaching some pretty high (for ultrarunning) intensities (80%+ VO2 Max), I am still metabolizing way more fat than carbs. This is an important takeaway for me, especially as I strategize for longer races. An athlete cannot replace the amount of calories they are burning quickly enough to expect an outside fuel source to meet their race-day caloric demands. A person may be able to physically consume enough, but their body would simply not be able to process the fuel quickly enough to stay ahead.” Zach Bitter.

At 84% VO2 Max Zach Bitter is still Metabolizing 76% Fat and 24% glycogen. These guys are world beaters, they are at the cutting edge of the Science, they have the most up to date data available and are using it to their advantage. Understanding their numbers enables them to maximise what they need to do as a Fat Adapted Athlete to Train Low, Race High and WIN.

David Grech