They key to a successful nutrition strategy lies in answering 3 questions:
1. How do I make sure my muscles get the “right fuel” at the “right time”?
2. How do I make sure that I get adequate hydration throughout the ride?
3. How do I make sure I don’t get any digestive issues?
To answers these 3 questions, you need to ask yourself 2 more:
1. What is my racing strategy?
2. How metabolically efficient am I? How do I tweak my nutrition accordingly?
Why is racing strategy important?
The level of effort you put out “during” the race will dictate the kind of fuel you’ll need.
The level of effort “during” the race can be very different from your “average effort” for the same race: you can have an “average” effort level of 80% whether you ride the entire race at 80% or ride sometimes at 60% and sometimes at 100%. However, the impact on your body, muscles and therefore fuel you need, is dramatic.
If you plan to “ride steady” and save your energy for the final sprint, you can afford to take on less fuel during the race. In fact, taking on too much fuel will harm your efforts because blood will be diverted towards your digestive system instead of muscles.
Riding steady means your body is able to better tap into your existing fat sources for fuel. It takes longer to convert fat to fuel, but riding steady means you don’t need “urgent” fuel, and as such you are able to tap into those fat sources. Ingesting too many carbs will put a stop to that process, will cause your insulin to spike, and may cause you to fatigue earlier.
Aim towards 2.5Kcal/Kg/hr of fuel, focusing on slow-burning carbs and some “easy to digest fats” to help promote fat burning (e.g. chia seeds or tree-nut butters).
Start 45min into the ride and take on fuel every 30min a little at a time.
If you plan to “ride aggressively” or anticipate having to respond to attacks or sprint to catch up after u-turns and roundabouts, then your ability to use fat for fuel will be significantly compromised. Your muscles will be relying primarily on glycogen (stored glucose) for fuel.
Muscles can store 60-90min worth of glycogen, and as such you will need to regularly replenish those stores during the ride.
Given the intensity and urgency for fuel, focus on easy to digest carbs that can be readily absorbed into your bloodstream and make their way to your muscles.
The 3 types of carbs at your disposal are: glucose, fructose and maltodextrin.
- Glucose is most readily and easily absorbed, and can make its way to your muscles the easiest.
- Fructose by contrast bypasses the blood and goes straight to the liver – as such, it takes longer for it to be used as fuel.
- Maltodextrin is artificially manufactured by attaching numerous glucose molecules together. Again, it takes longer to break it down and so is not as readily available.
The recommendation is to focus on glucose-based nutrition products or natural sources of glucose (e.g. maple syrup).
(In addition, the more complex the carb, the higher the chance of digestive problems – see below).
Aim towards 3.5-4.0Kcal/Kg/hr of fuel.
Start 30min into the ride and take on fuel every 30min a little at a time.
Important note on fuel absorption: remember that the more diluted the fuel is, the easier it is to get absorbed. Recommendation: prepare a well-measured bottle of fuel mixed with enough water to ease absorption.
How does my metabolic efficiency alter my fueling?
Metabolic efficiency is your body’s ability to use the “right fuel at the right intensity level”.
Metabolically efficient athletes (sometimes referred to as “fat-adapted”) are able to readily convert fat for fuel for a longer period of time and at higher intensity levels (still within the aerobic range), saving muscle glycogen for when it’s needed (attacks and sprints).
The more metabolically efficient you are, the less fuel you’ll need (since you can tap into your own fat sources). The strategies above assume “average” metabolic efficiency.
A high sugar diet (including frequent use of sports drinks and gels) often leads to a deterioration in metabolic efficiency. If you belong in that category, then you’re better off increasing your fuel intake by 20-30% to compensate accordingly.
For an easy and 0-cost test of your metabolic efficiency, go to http://www.systemendurance.com/blog/2015/10/27/do-this-test-to-find-out-if-youre-even-capable-of-losing-weight
What about Hydration? Do I need to take electrolytes?
Adequate hydration means getting enough water into your blood to maintain blood volume, blood viscosity (how think your blood is) and to deliver nutrients to muscles.
Not enough hydration means blood volume drops, putting pressure on your heart. Too much hydration means you dilute the nutrients in your bloodstream and risk hypernatremia.
After thousands of studies over what constitutes “ideal” hydration, the consensus today is the following: let your thirst drive your hydration. This of course assumes that you’re aware of your body’s signals and readily listen to them (for e.g. a headache means you’re borderline dehydrated already).
In addition, any food or fuel ingested needs to be accompanied by water. Not drinking enough water with your fuel means the concentration inside your stomach will increase, drawing water out of your bloodstream and into your stomach to re-establish the balance. This is often a primary cause of bloating and water slushing around in your stomach.
What about electrolytes?
The myth that electrolyte supplements will stop you from getting cramps has already been debunked by science. So is there a benefit in taking electrolytes?
The answer is: yes, albeit a small one. Water has a much lower concentration of electrolytes vs. your blood. By adding a small amount of electrolytes to your water, you are able to accelerate the rate of water absorption, emptying your stomach faster and improving your hydration.
Do electrolytes harm? Not really, so if you prefer to take electrolytes for the potential placebo effect on cramps, there is little downside as long as you drink enough water.
How do I avoid stomach upsets?
Digestive problems in endurance events are typically caused by one of 3 things:
– Slowdown in gastric emptying
Certain carbohydrates (e.g. fructose, maltodextrin) are much more prone to “sitting in the gut and fermenting”. The fermentation process is driven by bacteria feeding on such “complex” forms of carbohydrates, leading to gas and bloating.
Taking on too much fuel and too little water leads to a high concentration in the stomach, slowing down the emptying of the stomach (gastric emptying). This could lead to feeling bloated and water slushing around in the stomach.
An inflamed small or large intestine means that you’re not able to absorb nutrients from food, ultimately triggering diarrhea: your intestines looking to get rid of anything they cannot digest as quickly as possible.
So avoiding stomach upsets means:
1. Avoiding fermentable substances: fructose, maltodextrin, and most sweeteners
2. Drinking enough water to maintain balance in your stomach
3. Avoid foods that irritate the digestive system (for many, this means dairy, gluten, grains, corn, soy, and processed items).
Finally, remember to test any nutrition strategy prior to the race and under similar conditions.
Tony Hchaime is a Dubai-based endurance coach. He strongly believes in a science and evidence-based approach to sorts nutrition and training as a means to achieve a high level of performance without sacrificing health or longevity. You can read more of Tony’s tips on high performance in sports and other areas at www.SEPerform.com/blog.