The Big day is coming, you’ve done all the training and now is time to think about refueling the tank. Here is a basic (or not) checklist that – I hope – will help you.

First of, always keep in mind that we are all INDIVIDUALS, there is not one-size-fit-all recipe. This is just a guideline for you to adapt according to your needs.

The Art of Carb Loading

  • For any event lasting less than 2 hours roughly, the need is not crucial. Not saying that you should attempt a 5k PB glycogen depleted, but if you’ve been following a healthy diet with decent amount of carbs with reduced intensity volume. Carb load will not be necessary. Now, if you’re aiming for a Marathon, 70.3, Ironman or an ultra, you better go with a full tank.
  • During race week, with a reduced volume, you won’t need to binge on carbs everyday. The shift to carbohydrates should go up as the race approaches at a reasonable pace. Glycogen is as form of  glucose stored in your body in two sites: Your liver and your muscles. For the average person, it is about 100g and 400g respectively. How you replenish your stores depends on the timing and the type of sugar, but, remember that there is a limit for the rate of absorption, so there is no need to stuff your face of Onigiri (rice wrapped into Nori) within 30 minutes !
  • The liver glycogen is the primary source of blood glucose during the day, after an overnight fast, your liver glycogen will be almost depleted. Fructose is converted very quick and efficiently into liver glycogen. Muscle glycogen functions as an immediate reserve source of available glucose for muscle cells. The glycogen they store is available solely for internal use and is not shared with other cells, if you don’t use them (not exercising intensively), they will not go away ! Practically speaking, you don’t need to eat a 3 bowls of pasta/soba/udon/ramen/rice the night before, and as a result feeling bloated, having gas, and feeling crappy. You can slowly do it during the week leading to your race and you GI tract will thank you ! Other types of carbs than Fructose will make their way to your muscles
  • Timing is important. Although I said a monster meal is not necessary, taking most of your carbs around the workout is best: one to two hours before and after. It will require much less effort/energy to your body to synthesize glycogen as they will go through an “insulin-independent pathway” (the hormone Insulin responsible to regulate your blood sugar won’t be necessary, or at least much less will be required). You can enhance the process by eating your carbs with some protein. It will speed up the glycogen resynthesis and glycogen hypersaturation after workouts (Morifuji. 20045) and contribute and “enhance skeletal muscle remodelling and stimulate adaptations that promote an endurance phenotype” (Moore. 2014).


Coffee or not coffee?

Caffeine is the cheapest, most efficient legal ergogenic “drug” available on the market. Again, the effects are highly individual and depends on your genetics and whether you’re a usual coffee drinker or not.

First of, you might not respond to coffee shots just because your body does not respond to it (blame your parents for that). There’s nothing you can do about it. Also if you’re already having 5 cups of coffee per day on a daily basis, the effect will be way less pronounced than if you have say one single morning espresso for the day. Countless studies have been done on the topic and the effects ranges from none to high, with a tendency to improve time to exhaustion by around 3 or 4% (again, it is highly individual !!).

Dosage range from experiments is usually from 3mg to 6mg of caffeine per kilogram of body weight. For example if you decide to go for the lower range and if you weigh 65kg, then you would need to take 65 x 3 = 195mg (approx) of caffeine. To give you an idea, a regular single  Nespresso shot is about 65mg, so you would need to take 3 shots of Nespresso. As for timing, one hour before the race seem to be the right spot as  it is the time necessary to reach your bloodstream , enter your central nervous system and cross your blood brain barrier.

In practice:

During race week, make it simple, don’t overthink it too much. Eat simple carbs around your workout: Imo (sweet potatoes), white rice, soba (noodles made of buckwheat flour)  etc with some protein like fish, poultry, red meat, dairies (if you’re not lactose intolerant). Carb intake anywhere from 50% to 70% (no need to go crazy like 90%).  Try to avoid things that can cause GI distress like gluten (pasta, bread, ramen etc). Go simple and healthy whole food.

Quantity wise? listen to your body, stop when you’re full. Don’t force it. If you workout mid afternoon and it’s too early for dinner, a good example of a post workout meal would be a bowl of Yogurt + 1 or 2 bananas. The Yogurt will provide a nice amino acid profile for muscle repair and will enhance the absorption of the carbs in the bananas (mix of starch, sucrose and fructose, ideal profile for carb repletion)

The day before the race, your muscles should be well loaded by then, so you don’t need to have a heavy dinner. A good breakfast and lunch (no, I didn’t say a feast) and a light dinner will be enough (for example, 2 onigiri and 1 banana is enough).

For race morning, you want something very easy to digest. Again there is no need to eat too much, you want to feel light at the starting line ! Your legs should be fully replenished by now. All you need to fill up is your liver glycogen, which can store only about 100g of carbs (400 calories).

Try to eat early enough about 2-3 hours before the start. Whether two or three hours will depend on how fast you digest. Eating too early and you might experience a sugar low due to the insulin spike from simple carbs. Eating too late and you might feel heavy. It is highly individual but a starting point is 100kcal per hour before the race. So if you eat two hours before, you can start with 200 calories (1 onigiri for example). This is the conservative approach, of course if you usually have more and feel fine go for it.  Remember that there is no much need to go significantly higher than about 400kcal.

Digestion is a complex process and demands lots of energy. That day, you will need any bit of energy your body can provide. Eating too much before will deviate part of the bloodflow to your GI tract, instead of being fully available for your legs muscles ! You want to avoid that ! If you decide to go for caffeine, do it one hour before the start.

Last but not least, it is common sense but still many people fail to apply this simple rule: Do not try anything new on your A-race morning !




  • van Loon, Luc JC, et al. “Maximizing postexercise muscle glycogen synthesis: carbohydrate supplementation and the application of amino acid or protein hydrolysate mixtures.” The American Journal of Clinical Nutrition 72.1 (2000): 106-111.
  • Stellingwerff, T., & Cox, G. R. (2014). Systematic Review: Carbohydrate Supplementation on Exercise Performance or Capacity of Varying Durations. Applied Physiology, Nutrition, and Metabolism (2014).
  • Burke, L. M. “Fueling strategies to optimize performance: training high or training low?.” Scandinavian Journal of Medicine & Science in Sports 20.s2 (2010): 48-58.
  • Burke, Louise M., et al. “Carbohydrates for training and competition.” Journal of Sports Sciences 29.sup1 (2011): S17-S27.
  • Morifuji, Masashi, et al. “Dietary whey protein increases liver and skeletal muscle glycogen levels in exercise-trained rats.” British Journal of Nutrition 93.04 (2005): 439-445.
  • Moore, Daniel R., et al. “Beyond muscle hypertrophy: why dietary protein is important for endurance athletes 1.” Applied Physiology, Nutrition, and Metabolism 39.999 (2014): 1-11.
  • , “Exercise endurance 1, 3, and 6 h after caffeine ingestion in caffeine users and nonusers”
  • Ben Desbrow, et al. “The effects of different doses of caffeine on endurance cycling time trial performance.” Journal of Sports Sciences 2012;30(2):115-20


Otaku Ultramarathoner - Strength & Conditioning NASM Certified Personal Trainer - NAASFP certified Running Coach - Pn1 Nutrition Coach

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Race Week Nutrition 101

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