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The Doctor

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Everything posted by The Doctor

  1. You can start sipping a carbohydrate drink about 20min before the start once you are warmed up. That will prime the stomach and start absorption from the word go. Drink about 200ml total.
  2. Yes. We will be at CWC and ReCycle stands I will be at the CWC stand on Thurs, Fri, Sat afternoons should you want to pop around for any advise.
  3. And I forgot to mention. That last gel is just in case you hit the wall and need emergency supplies.
  4. Best strategy would be 750ml marathon and 750ml carbofuel. Take along 1 bar and 4 gels. Drink the marathon first for 90min then switch. Gels at the end of each hour and 1 in reserve. Bar at halfway point. However, not having trained your gut you might not tolerate the carbohydrate load. In which case it would be better to leave out the bar (which will also be hardest to consume in the bunch). Not sure I'm supposed to tell people to use less of our product but there you have it.
  5. There are really 2 parts to this question that needs answering. 1) Why are you drinking 100g / hr of maltodextrin? Maltodextrin is composed entirely of glucose and max absorption rates in well trained athletes are in the realms of 60g/hr. You are therefore consuming an extra 40g which is just pooling in your GIT and will increase the osmolality, delay fluid absorption and may also cause GI distress (although you don't seem to have any). If you want to consume > 60g/hr you will need to add fructose. 2) Gastric emptying is determined by a complex interaction of fluid osmolality, temperature, composition, volume and other factors. This review will give you a really good overview: http://www.pubpdf.com/pub/24715561/Optimal-composition-of-fluid-replacement-beverages Figure 11 is pertinent, as is the discussion on page 600. To interpret figure 11 look at the % absorbed in 60min. For an 8% solution it is 40% of volume vs 60% of a 4% solution. 40% of 500ml 8% solution = 16g CHO delivered 50% of 500ml 6% solution = 15g CHO delivered 60% of 500ml 4% solution = 12g CHO delivered Although higher CHO concentrations delay gastric emptying, the higher CHO load results in a peak delivery at approximately 8%. Although there are multiple factors that vary this as per the review. 3) Lastly - 500ml x 8% = 40g/hr. Add a gel with 30g and a bar (45g) every 2 hours. You don't need to drink all of the carbs. Solids and gels are absorbed at good rates too.
  6. Bad timing. Gastro the week before the race and then caught a cold on the day. I tried one lap but realised I was doing harm and called it a day.
  7. Current evidence for exogenous ketones as a fuel source is not at all convincing.
  8. Thanks. I appreciate the acknowledgment. As a scientist it is always important to remember that there are absolutely NO scientific facts. There is only scientific consensus. Consensus often changes based on the existing evidence. New evidence -> New consensus. So I keep an open mind and let the data tell us what we currently know to be best practice.
  9. That is a fair interpretation. Just note that you could also do 3 hours of hard riding with a LCHF strategy. However then it would ideally need to be a constant intensity.
  10. That's probably the worst strategy. See above post. Add 2 training sessions each week with carbs and the rest fasted. You will notice a big improvement in races.
  11. The carb / fat question is a very interesting one for which we don't have enough answers yet. We are doing quite a bit of research in this domain at the moment and recently published a paper on this. Link here: https://www.ncbi.nlm.nih.gov/pubmed/26918583 Here is what we know at the moment: During exercise the primary fuel source is carbohydrate. Peak carbohydrate oxidation rates are as high as 8g/min at very high intensities in elite athletes. We used to think that peak fat oxidation rates were always below 1g/min as nobody had ever reported higher than this in any study. Most elite athletes have peak fat oxidation rates of about 0.6g/min When people started banting and also exercising new data emerged that showed that on a LCHF diet, peak fat oxidation rates could reach as high 1.8g/min in a small number of athletes. That is more than twice what we previously thought was possible. This is still quite a few orders of magnitude lower than CHO oxidation rates though. However, that changes our paradigm to some extent with respect to fuelling for endurance sports. A fat oxidation rate of >1.5g/min can sustain an intensity equivalent to approximately 65% of VO2max power. Which is a fairly easonable pace. It is therefore possible to fuel without any carbs for an ultra-endurance event when the pace is not excessively high and is kept constant. A good example would be an age grouper or competitive Ironman athlete on a relatively flat course profile. Things get a little more complicated when you start looking at sports in which the pace varies significantly e.g. road or MTB Habitual LCHF athletes have down regulated CHO absorption rates and also have lower oxidative and glycolytic capacity for CHO. As such, the carbs that they do have stored are not as accessible as they would be in a mixed diet athlete. In addition, they cannot absorb CHO at the same rate as a mixed diet athlete. The study posted above showed that they also do not convert fats or proteins into glucose (gluconeogenesis) at a faster rate than mixed diet athletes. So they are somewhat dependent on fat as a source of energy (or so it seems from our data to date). The upside is that fat is a virtually limitless energy supply and you will therefore never bonk as a LCHF athlete. Many LCHF athletes are completing events like the Ironman on fluids alone. No exogenous fuel! Whether the LCHF diet is a good diet for overall health in the long term is still unclear. So the above points relate solely to performance. The downside is that LCHF can result in greater fatigue in the first few months and may also suppress the immune response. We have unpublished data from ironman athletes that demonstrates higher rates of infections for LCHF athletes than their traditional counterparts. Monitoring fatigue is therefore very important when following a LCHF diet. Adaptation to LCHF as an athlete also takes a few months. It's not something you can switch to overnight. A new strategy that has emerged in recent years is one which attempts to gain some benefit from both fats and CHO. This is know as periodised nutrition. It involves 2-3 fasted exercise sessions each week to stimulate fat oxidation rates. The other 2-3 sessions are down with maximal CHO feeding rates (60-90g/hr) to stimulate the up-regulation of CHO transporters in the gut (training the gut) and to maintain CHO oxidation capacity and glycolysis in the muscle. It also results in a leaner athlete. In races (particularly ultra-distance) the athlete will sometimes fuel with a mix of carbs and fats in the first few hours and then switch to CHO in the last 2 hours. Typical is a Tour De France mountain stage in which the first few climbs are ridden at a lower intensity and then the attacks start to happen on the last climb. With this strategy we can get athletes to achieve fat oxidation rates that are higher than traditional mixed diet athletes but they are still below 1g/min. However, it creates a larger fuel tank while maintaining the ability to perform very high intensity exercise. We are busy writing up data on a LCHF ultra athlete that was tested in LCHF state and again in when using periodised nutrition. The periodised nutrition improved 20km TT power but did not improve 100km TT. So this does confirm our hypothesis to some extent. We will be publishing this data soon. I hope that gives some clarification. We still need to do answer a lot of questions but the science is definitely being conducted and will be published in the coming years.
  12. Sucrose is 50:50 Glucose and fructose So in essence it has the right ingredients but I can't confirm that they are in the right concentration.
  13. Your drinking strategy is spot on. Did you figure that out by trial and error or from our chart? http://www.cadencenutrition.com/wp-content/uploads/2016/10/Cadence-How-to-Use.png
  14. Maltodextrin is composed of chains of dextrose. These all compete for absorption across sodium dependant glucose uptake transporter 1 (S-GLUT1). As a result the peak absorption rate is about 60g/hr. Adding Fructose results in up to100g/hr total carbohydrate absorption. This is because fructose has it's own transports (GLUT-5). 2/3 maltodextrin and 1/3 fructose results in higher exogenous carb oxidation (using more ingested carbs and saving your endogenous stores), better performance, lower gastro-intestinal symptoms than any other carbohydrate mix. Which is why the most popular products GU and Powerbar both use this formula. They would be silly to not use the best possible formulation. The science is published. it's not some secret formula. The only 2 other products on the market that I am aware of that use the same formulation are Hi-5 and Cadence Nutrition. There might be others so please point them out if that's the case. Using a product with any other formulation is definitely going to make you slower and possibly also cause you to develop nausea or diahorrea if you try to ingest the same rate as with a 2:1 maltodextrin fructose mix. So I would and do happily recommend any one of the 4 products above to athletes, not just Cadence Nutrition. If you've been to one of my talks you will have noted so. Nice summary here by Jeukendrup, including a 32 references for those who are keen readers. http://www.gssiweb.org/Article/sse-108-multiple-transportable-carbohydrates-and-their-benefits
  15. I was responding to the 2 posts. One that said that the statement on our website was not supported by the evidence. Which it clearly is. The other simply said "Fake news" But to respond to your point: You are correct. We previously believed (without evidence) that drinking carbohydrate would result in the fastest delivery rate. However, whether you drink, use gels or eat solids, the absorption rates are fairly similar and so you can drink simply to hydrate and eat the calories. However, calculating CHO intake with solids is a little trickier and may result in peaks and troughs that are not ideal. With regards to fluid intake: Dilute (low osmolality) fluid results in higher gastric emptying rates but with increasing carbohydrate concentrations the carb delivery initially increases in rate progressively until it peaks with concentrations of about 8% (8g/100ml solution). Above that concentration the gastric emptying rate slows down too much and the carb delivery decreases again. Which is why most commercial drinks are approximately 8% (40g CHO per 500mls) when mixed correctly.
  16. I see there was a post that he/she is a Cadence employee. Definitely not but glad to see we have some fans. Clearly also takes the time to read through the evidence. Regarding the dehydration and it's ergolytic effects: The research supporting this was largely funded by Gatorade and industry. Yes, dehydration in excess of 3% can impair performance. However, dehydration to that extent is rare in normal race conditions where athletes drink to thirst. Hence the point that athletes should primarily drink to consume exogenous carbohydrate and not simply to replace fluids. Regarding recent (post 2013) INDEPENDENTLY conducted research on this issue: http://bjsm.bmj.com/content/early/2013/09/20/bjsports-2013-092417.short http://journals.humankinetics.com/doi/abs/10.1123/ijsnem.2016-0194 http://www.wemjournal.org/article/S1080-6032(16)00110-1/fulltext http://journals.lww.com/nsca-jscr/Abstract/2015/01000/Two_Percent_Hypohydration_Does_Not_Impair.15.aspx
  17. Just in case my first post was not clear. As far as the UCI rules are concerned the CSA ruling is incorrect. The policy and appropriate sanction apply irrespective of whether the rider is found with needles in our out of competition. i.e. at any time.
  18. The rules pertaining to 13.03.052 apply to both in and out of competition periods. Rule 13.03.052 is a sub clause relating to rider or full team being withdrawn from races following a violation of the no needle policy. It refers to additional sanctions not covered in 13.03.057. Hence the words "In addition to..." This is not at all ambiguous. Full rules follow. " 13.3.052 The injection of any substance to any site of a rider’s body is prohibited unless all of the following conditions are met: 1. The injection must be medically justified based on best practice. Justification includes physical examination by a certified medical doctor and an appropriately documented diagnosis, medication and route of administration; 2. There is no alternative treatment without injection available; 3. The injection must respect the manufacturer-approved indication of the medication; 4. The injection must be administered by a certified medical professional except where normal practice is that the patient with a disease requiring injections injects him/herself (for example diabetes); 5. The injection must be reported immediately and in writing not later than 24 hours afterwards to the UCI Doctor (via email [medical@uci.ch] or fax [+41 24 468 59 48]), except for riders a. With a valid TUE; b. Vaccination c. When the injection is received during hospital treatment or clinical examination; d. When normal practice is that the patient with a disease requiring injections injects him/herself. The report must be made by the medical doctor having examined the rider and must include the confirmation that a physical examination took place, the diagnosis, medication and route of administration. Where applicable it shall also include the prescription referred to in article 13.1.065. Comment to par. 5: the report may be sent by the medical doctor or the rider. The rider is responsible for the report to be sent. The prohibition under article 13.3.052 applies to any substance that is injected, whether endogenous or exogenous, whether prohibited under the UCI Anti-Doping Rules or not. 13.3.054 The prohibition under article 13.3.052 applies to any type of injection: intravenous, intramuscular, intra-articular, peri-articular, peri-tendinous, epidural, intra-dermal, subcutaneous, etc. 13.3.055 In case of a local injection of glucocorticosteroids, which is subject also to the UCI Anti-Doping Rules and the Prohibited List, the rider must rest and is excluded from competition for 8 days. The medical doctor having prescribed the injection shall prescribe this rest in writing to the rider and add to the documentation referred to in article 13.3.052.1 a copy of such prescription signed by him/herself and the rider. 13.3.056 In case of an injection of a prohibited substance, in addition to the requirements of articles 13.3.052 and 13.3.055, a Therapeutic Use Exemption remains required and the procedure foreseen in the Chapter IV of the UCI Anti-Doping Rules has to be followed. 13.3.057 The following penalties may be imposed by the UCI Disciplinary Commission in the event of an infringement of article 13.3.052: suspension from eight days to six months and/or a fine of CHF 1,000 to CHF 100,000; in the case of a second offence within two years of the first: a suspension of at least six months or lifetime suspension and a fine of CHF 10,000 to CHF 200,000. The penalties shall apply to any licence-holder found to have committed the violation or to be an accomplice; application of article 1.1.086 is reserved; 13.3.058 In addition to the sanctions stipulated in article 13.3.057 the following shall apply: 1. In case of infringement of article 13.3.055 all results obtained by the rider in the 48 hours period shall be disqualified. 2. In case a violation of article 13.3.052 occurs at a race the licence holder(s) concerned and, where appropriate, the whole team of the licence holder(s) at fault may be excluded from the race; in this respect the possession of objects used or fit for an injection shall be presumed to constitute evidence of a violation of article 13.3.052 having been committed except if the objects are in the possession of the medical doctor who has made the report referred to in article 13.3.052.5 and are covered by such report and except for those objects that may reasonably be in a medical doctor’s possession. The exclusion may be decided by the president of the commissaires’ panel after having given the persons concerned the opportunity to be heard or by the president of the UCI Disciplinary Commission upon report by the president of the commissaires’ panel.
  19. Or try the Red Berry Carbofuel. Some like the zing, some like it sweet. We cater to everyone.
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