LCHF and the athlete: The Plews approach

Sfuels, a ketogenic fuel for endurance athletes recently had Dan Plews host a Facebook live event regarding his LCHF training and daily diet. Now those of you have listened to our Fitter Radio podcast will know Dan from the Plews and Prof segment. He’s an exercise physiologist who last year was the overall age group winner at Kona World Championships in a record time of 8:24. He’s been working in exercise physiology for the last 15 years and has a number of research papers both related to this, and in the ketogenic diet space (for athletes), one of which I posted about last year. Because I love Dan’s work (and this area in general) I wanted to outline for you what he spoke about in the Facebook live for those people, athlete or otherwise, that are interested. This week, due to length, I’ll cover the normal diet, and next week I’ll outline his pre-race and race-day strategy.

As a bit of background, Dan has been doing triathlon forever, however came into LCHF when he was at the Olympics as an exercise physiologist and came across work by Tim Noakes (who has heralded the latest Banting movement in South Africa). From 2012 he made a decision to give it a crack. Even now, though, six years after embarking on LCHF training and nutrition, Dan notes that adaptations are still occurring, and puts his incremental improvements in performance in the Ironman distance finishing times (in hours:minutes) being: 9:22, 9:11, 9:12, 8:54, 8:35 and 8.24 Kona 2018) down to not only the consistency of training , but the consistency of the dietary approach.

What is important in LCHF and endurance training? The end goal for performance is to conserve as much energy as possible – fuel availability is the limiting factor over such a long distance. We can’t store too much carbohydrate – around 2000 Calories compared to 40000 Calories of fat that is stored in even the leanest individuals. The problem, though, is that people can’t access their fat stores to exercise at a high intensity. Or even, for many endurance athletes, at a lower intensity (where we should be able to burn fat). The type of diet we eat influences our fuel preference when we exercise, and the modern diet (where carbohydrate is the predominant available nutrient) makes athletes much more reliant on carbohydrate which – like kindling on a fire – is likely to run out quickly.  We want to be metabolically flexible, that is, to burn more fat as a fuel source and only use carbohydrate when we really need it. Dan has tested his fuel utilisation in a laboratory and can burn fat at 1.3g/minute (the FASTER study reported around 1.6g/minute) – most people are around 0.6g/minute or thereabouts. However research such as that done by Volek and colleagues have shown it is possible to shift that if you go LCHF. From the testing that Dan has done, he knows that at his race intensity on the bike, an average 260 watts, his fuel utilisation is around 66% from fat stores. This allows him to preserve a lot of carbohydrate when working at this race pace intensity.

Ideally, that preservation of carbohydrate stores to use at the back end of a race when energy availability is limited should be the aim of the endurance athlete (and is extremely challenging if they are burning predominantly carbohydrate from the start). In addition, the lower LCHF diet means having lower blood glucose levels on a day-to-day basis,  important for overall health and body composition goals too. Higher sugars equals higher insulin, which is a nutrient delivery hormone – therefore there is more opportunity for fatty acids in the blood stream being stored in our fat tissue. Don’t go thinking we want rock bottom insulin levels all of the time, as insulin itself is critical for life! However ideally our levels would be low outside of the time period around meals, as elevated insulin is linked to a number of metabolic disease processes. In addition, when following a LCHF approach, we have lower stores of carbohydrate, which makes us more sensitive to the signalling for fat adaptation and upregulating of fat oxidation pathways.

So… the details?

Dan’s diet on a day-to-day basis:

  • Coffee with cream, collagen and MCT (medium chain triglyceride, our body can’t store this and is an easily used energy source)
  • SFuel bar (low carb snack)
  • Training – doesn’t eat during training, but if he does it may be a SFuel drink (MCT/branched chain amino acid (BCAA) drink mixed with some other compounds, but it is a higher fat option)
  • Breakfast is eggs, avocado, some vegetables
  • Lunch is tuna salad or similar. During heavier training load, he may add a bit of paleo bread (around 20g carbohydrate, similar to normal bread but this is made of better quality ingredients)
  • Dinner is salad with a steak
  • Snacks may be macadamias, almonds and pickles.
  • Fruit may come into it from time to time, particularly as the training load and intensity ramps up.

While not ketogenic in way that he eats, he will still likely be in ketosis during the day – by virtue of training and his normal diet is low carbohydrate – it’s around 80g – 100g carbs per day, thus naturally depleting his stored carbohydrate (glycogen). Ketogenesis is a is a physiological state, not a diet, thus it’s less important to stick rigidly to foods labelled as ketogenic and to think more globally about it. My athlete plan  is based around these dietary principles, and there are likely some nuances for the female athlete, but this general approach works well for most people I work with. It could be important for a carbohydrate refeed 1-2x per fortnight if following a very low carbohydrate diet, and that’s something I recommend to my athletes on the basis that hormonal responses will be favourable. This isn’t something I’ve seen a lot in the literature, but based more on clinical experience (and may be more important for the leaner athlete).

As I mentioned, I’ll cover off the race day side of things next week. However, if you’re keen to know more about what Dan recommends, then definitely check out his new site – he’s developing an online course that details specifics for coach and athlete alike, and is releasing it soon!


Kona 2018. (PC: