The Plews on racing LCHF

Last week I detailed Kona Ironman age-group champion Dan Plews’ daily and training nutrition using a LCHF approach. How does this change in the lead up to an event, and what does he do on race day?

Like conventional sports nutrition principles, there is somewhat of a carbohydrate loading phase pre-race. This isn’t the 500-600g of carbohydrate that is recommended for most athletes in the three days before (which generally leaves an athlete feeling lethargic and bloated), however it is more than he would generally eat. Don’t forget that tapering for a race is, in effect, carbo loading, as the muscle glycogen stores are not depleted during training and it allows them the chance to be replenished and not in the deficit they normally are. Based on Rowlands paper which showed that a higher fat diet with a preload of carbohydrates, he’s dialled in his approach that Dan now feels works really well for him. He lifts his carbohydrate intake from the 80-100g he typically eats in the days prior. On the Wednesday (for a Saturday race), he will include additional potato or sweet potato in his evening meal, taking him to ~125g carbs per day. This increases to ~175g per day on Thursday and Friday (the two days before the race) – including fruit alongside the potato or sweet potato. In addition, he makes sure snacks etc on hand are low carbohydrate so  not to be caught out during the lead up period with having to rely on the petrol station or four square options. If you do have to rely on these, and are looking for lower carbohydrate, then biltong, cheese snacks, even lower carbohydrate protein bars can be good stop gaps. On race morning before Dan’s Kona race he opted for was porridge: oats with a bit of Super Starch added, which is a slow release carbohydrate to not inhibit fat burning, and is a higher molecular weight carbohydrate, so it is easier to digest.

During the race:

Despite research studies in this area using a ‘train low glycogen, race low glycogen’ model to determine the efficacy of a LCHF approach for sports performance, in practice Dan follows what practitioners advocate: a ‘train low, race high’ model. Ideally, the train low approach has enabled you to increase your efficiency to burn fat as a fuel source in addition to using carbohydrate that you have stored or take on board, thus maximising the amount of fuel you have available. Dan takes in around 50g carbohydrate per hour;  because he is very efficient at burning fat, he doesn’t need as much carbohydrate as he would otherwise. A real benefit of this is that it minimises the likelihood of gut issues many endurance athletes experience during a long event – the more carbohydrate fuel you have to take on board, the more opportunity there is to get the dose wrong. Importantly though, the more fatigued you become, the more your body will divert blood supply away from the gut to the muscles, and thus impacting on your ability to digest the fuel.  During Kona Dan used energy blocks with gels on the bike, and a couple of gels with some swigs of sports drink or coke during the run. His paper Different Horses on the Same Courses outlines how to take this individualistic approach to fuelling, as will his online course that you can sign up to by clicking here.

Finally, post-race, Dan gets back on board the LCHF approach fairly swiftly, as he has seen the impact that a higher carbohydrate fuelling day has on his blood glucose level across the course of the following week. It certainly doesn’t reduce down to normal levels the day after, and it’s likely that inflammation and muscle damage impacts on this too. Your best bet is to (as soon as possible) get back to your LCHF diet and help your recovery process.

LCHF for the top end:

Whilst LCHF is increasingly more accepted in the endurance space as part of the approach, what about at that top end – does it limit performance there? There is very little quality research on this, however Dan’s research group found that there was no detriment to perform high intensity intervals (as I blogged about here), but the jury is definitely out on this point and I wonder if, like many things, it is individual. A person’s ability to metabolise fat as a fuel source and use it at a higher intensity is trainable for sure (that’s what fat adaptation is all about), but there could be individuals who are less able to produce ketones to be used for energy – this is speculation though on my part. Yes, there is a down regulation in pyruvate dehydrogenase which helps turn stored carbohydrate into glucose for energy, however the importance of this is questionable given the increased availability of fat for fuel, and there may be other enzymes upregulated to counteract this change in the fuel use. A potential way around this issue (and to ensure glucose metabolism is continued on your LCHF approach) is to do higher intensity efforts in training that force liver to convert glycogen to glucose – thus keeping glucose oxidation pathways high. I’m also beginning to recommend that people take on a small amount of glucose pre-high intensity sessions if they are beginning the fat adaptation phase during a training cycle that incorporates higher intensity efforts. Ideally your fat adaptation phase will occur during base training when we can keep intensity low. But that isn’t always possible. Fifteen-20g glucose prior to training for these high intensity sessions can keep output high but is unlikely to be enough to “ruin” your adaptation process. Again, there is no research behind these numbers, but from a practice perspective I’ve seen this work well.

Finally, you know I’m an advocate of ketones to help support training whilst lower carbohydrate, and it certainly has helped me and many of my clients. We don’t at this point know enough about ketone utilisation in the body and whether taking exogenous ketones downregulates the body’s ability to produce them. This is an emerging field we are looking at with interest with regards to dosage, timing, type of ketone supplement etc. There has been decades of research into carbohydrate as a performance enhancer, and we can probably expect that it will take a few years of research for these questions to be answered in the science research space. Trying them yourself is likely the best approach to see how they impact your own performance (and I can help you with that).

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Plews at Kona (PC http://www.trizone.com.au)

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!

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Kona 2018. (PC: oxygenaddict.com)

Another reason to love coffee…

Love your coffee? Here’s another reason to pour yourself a cup. A recently published study should the consumption of a dark roasted coffee brew (500ml) daily for one month resulted in a 23 percent reduction in DNA damage to white blood cells compared to baseline levels. The protective feature of coffee is thought to be the polyphenols that are found in coffee. These bioactive ingredients (such as caffeic acid, catechol, hydroxyhydroquinone, trigonelline and the alkylpyridinium compounds) have been studied for their antioxidant and anti-inflammatory properties. They are able to mop up reactive oxidative stress (ROS) molecules that are the byproduct of metabolism. Obviously a small amount of ROS is necessary, however too much can overwhelm our anti-inflammatory and antioxidant system, causing increased inflammation and the reduction in the ability for these pathways to function, causing DNA damage.

DNA damage accelerates ageing and is the underlying cause of the growth of carcinogenic cells in the body. It leads to telomere shortening – telomeres are like small caps on the end of your DNA chromosomes, protecting them from damage, and are used as a biomarker for ageing. The study was a randomised controlled trial; therefore, it is able to establish causation (unlike a lot of nutrition research, which is largely observational in nature).It is consistent with other studies that show a reduction in DNA damage after even short term exposure (such as this study, where healthy volunteers showed a reduction in damage after only 2h of drinking coffee). The current research was conducted in both healthy men and women, and the 500ml of coffee per day equated to around 372mg caffeine daily – equal to around four cups of espresso. That sounds like a lot of coffee (and it is!) however this is consistent with other observational and clinical trial research that has shown a reduction in cardiovascular disease risk, cancer incidence and all-cause mortality for people who habitually consume around 4-5 cups of coffee per day. This latest study adds to a body of knowledge regarding the health benefits of coffee. The polyphenols mentioned above help protect us from type 2 diabetes, stroke and cardiovascular disease, with improvements being seen in glucose and insulin metabolism (important for blood sugar control), blood pressure and markers of inflammation in the body.

I’ve talked before on the health benefits we see in coffee, and though this is great news for coffee drinkers, let’s not forget there is a fairly substantial proportion of people who are sensitive to the caffeine in the coffee and can’t tolerate its stimulant effects. Caffeine is metabolised in the liver, with the CYP1A2 enzyme responsible for detoxifying most of the caffeine. Our ability to produce this enzyme is coded by our genes, and there is variation as to how active this is for each individual. Those that have an active gene are able to metabolise caffeine efficiently, therefore the stimulating effects of caffeine are mild and short-acting. This may affect their enjoyment of caffeine and clearly their ability to tolerate it. The opposite is also true – someone with reduced activity of the gene will metabolise caffeine more slowly and its effects will be longer lasting and more noticeable. You can find out your genetic ability to tolerate caffeine through a Fitgenes DNA test(PM me for more information).  In addition to the genetic differences, environmental elements also influence our ability to tolerate caffeine. Even if you are a fast metaboliser, stress and lack of sleep can impact on caffeine’s effects – ramping up cortisol levels and with it anxiety and blood sugar dysregulation. Three coffees a day when on holiday and in a relaxed state may not be a problem, however when a work deadline is looming and you’ve been running on little more than petrol fumes rather than sleep, it is a different story.

With the present research, as the health benefits are from polyphenols present in the coffee, rather than the caffeine, the reduction in DNA damage may well be seen in decaffeinated coffee too, with previous research finding benefits with regards to type 2 diabetes and liver damage when consuming both decaffeinated and caffeinated coffee. has found health benefits from drinking this. However, without clinical trials to confirm this, at this stage it is unknown.

Coffee cup with saucer and beans on wooden table.

Obligatory cup of coffee (PC:stockphotos)