Monday, 9 May 2011

Fat-Loading and the FITT Principles for Taper Training

I’m a week away from the challenge Hub 24hour endurance race and my taper is in full swing. Every Endurance athlete will have a slightly unique training regime in the 7-21 days prior to an event but the fundamentals are always the same- drop the training intensity and allow your body time to recover. It has also become pretty common knowledge that you should not completely stop training nor change too much. I (as well as many others) tend to follow the FITT training principles in order to slowly drop the demand of training without taking the body out of its naturally rhythm. FITT stands for Frequency, Intensity, Type and Time. For example you should be looking to change just 1 of these 4 principles per week of your taper. If you have a two week taper, I generally do 12 days*, you will adjust one in the first week then add another in the second. I would always keep the Frequency the same as it keeps that rhythm but what you change between the other 3 will be event and individual dependant. For my 24hour race I have dropped TIME in the first week, which translates to the amount of mileage I’m doing in each session. The second week I am dropping the INTENSITY along with the TIME- this now means I am running at a slower speed and at a lower heart rate for the same sessions. I have personally toyed with dropping different things and sometimes everything as a test to see how much benefit my body would get from more rest, I have generally found that I feel lethargic and sluggish at the start of a race after periods of complete rest.
* Lots of interesting taper research in ‘the medicine & Science in Sports & Exercise Journal 2003’
These thoughts and ideas on Taper training have generally been exhausted on internet forums, magazines and journals but the effects on Nutrition Taper tend to be a little more subjective. The Carbo-load conversation is now ridiculously boring yet nobody has decided exactly how long it should be, specific percentages on carb intake to total calories and whether or not you should still be Carbo-loading in the final 24hours before competition ('running light' theory). I have even seen an article suggesting that we ONLY need to carbo-load 24hours before competition and no more (
All the research leads to more questions than answers. But questions are good as ultimately they will drive human performance forward as we seek the solution. And that leads me to Fat-Loading, yup, Fat-Loading. There is some research out but there is way less questions and even less answers. This all comes down to the fact that fat-loading is a concept only ever adopted by ultra distance athletes and there is way less ultra distance athletes than in most other sports. And when I say ultra distance I don’t mean 50mile runners or Ironman triathletes, Im talking about 100mile+ runners and double+ Ironman athletes- proper underground sports performers.
For the 24hour challenge I am once again fat-loading (5days) followed by carbo-loading (3days). Before I continue I am not writing this to say I am right, I am just putting some ideas across about what works for me and to give the less discussed fat-load concept some air time.
So why I fat-load:
The most basic answer is that carbohydrates only provide 4-4.5kcal per gram as opposed to the 8-9kcal provided by fat. During sports performance it is widely reported that we can only consume approximately 300kcals per hour (weight, intensity, temperature and person dependant). When we will be burning in excess of 700kcal per hour it becomes very apparent that we will not have enough glycogen/carbohydrate storage capacity to fuel performance for much more than 3 hours. At this point we either need help from the calories we consume (which will not be enough), from fat oxidation or from protein synthesis. If it comes from protein synthesis within the muscles than this will lead to muscle atrophy. So the ideal solution is fat oxidation, problem number 1......nearly all successful ultra endurance athletes have a body fat percentage under 10. That is not a lot of fat, hence a small increase in the fat consumed before competition can become very useful after 4+hours of competition (especially 24hours!).
Several other methods of increasing fat oxidation have been used such as drugs like heparin and other dangerous methods like the intravenous infusion of fat. But it wasn’t until the arrival of positive studies on medium chain triglycerides that fat-loading became popular use by ultra endurance athletes. In scientific terms-
"The depletion or reduction of bodily carbohydrate reserves is associated with fatigue during endurance exercise. Various carbohydrate supplementation and exercise regimens have been used experimentally to increase carbohydrate reserves before exercise or to maintain the availability of carbohydrate for oxidation during exercise. On the other hand, the improved endurance capability observed after aerobic training has been attributed to an increased oxidation of fat relative to carbohydrate; this carbohydrate sparing presumably delays the point at which reduced carbohydrate reserves cause fatigue. This effect has led to the suggestion that a greater availability of fat during exercise can improve performance via the carbohydrate-sparing effect of "fat loading." Sherman WV and Leenders N. Fat-loading: the next magic Bullet? (International Journal of Sports Nutrition)

The key summerised advantages of fat-loading are all related to delayed onset of fatigue, slower muscle atrophy and better recovery. I could write about this for page after page but I would get ridiculously boring, actually saying ridiculous reminds me of something....what is it with my North American friends all saying ‘ridonkulous’ lately? It is definitely not a real word, it’s a stupid word and it should not replace ridiculous. Have I missed something here? Who started it?

Anyway, if you have any more interest in the fat-load concept then leave a comment with any questions and I can send you some links if I can’t answer them myself. I also encourage you to read chapter 13 in The complete book of SPORTS NUTRITION: A practical guide to eating for Sport by Shelly Meltzer and Cecily Fuller.

Below I have left an exert of what a typical fat-load day looks like for me. You will notice that the fat content is not outrageously high as I don’t want to put on weight. Simply put all it needs is a few grams removed from protein and carbs and added to the fats ratio. This type of diet also makes it very easy to quickly transition into a high carb diet again. Once more any questions please ask- I hope you find this useful

BREAKFAST Carbs(g) Protein(g) Fat(g)
Porridge,Milk 75 25 45
Banana 15 0 0
Mixed seeds and Nuts 0 5 15

3x Pitta Bread w/peanut butter 65 15 15
½ avocado 0 0 10
Banana 15 0 0

250g Chicken 0 70 15
Cup of rice/pasta 30 5 0
Salad&veg 0 0 0
4 rashers bacon 0 0 20
Mixed nuts and seeds 15 5 5

100g chocolate 60 10 30
Peanuts and almonds 20 30 90
Raisins 15 0 0
SNACK TOTALS 95 40 120

DAILY TOTAL 310 165 245


  1. If we're looking for improved or encouraged fat oxidation then would it not be beneficial to fat-load during heavy training cycles too? Yet we don't hear of this? Why, if its a good thing? Not entirely convinced due to this but the principles are sound enough. I think it has greater benefit at or during competition as carb replenishment is hard on such little consumption of food

  2. get fit or die tryin11 May 2011 at 00:34

    Someone will corretc me if I'm wrong but the benefits if fat consumption during competition is less because we are hugely unlikely to deplete our fat stores. We should merely be attempting calorie replacement (despite an obvious deficeincy as time goes on). I know their is a particular way to train during fat and carb load phases which have some benefit and sound research behind too. For me fat load is just about topping up, I can't imagine oxidation will be greatly improved in one 5-7 day cycle a week before competition. The delayed muscle breakdown is worth looking at for sure. My quads are half the size after an ironman so I guess I'm using the protein within the muscle as fuel