By Daniel van der Laaan
This is something Jesse and I have been discussing a lot recently. I’ve been working on getting rid of track weight (let’s be honest, also some holiday weight). I have gone from 88kg post holiday/off-season in mid-December down to just under 75kg a few days ago which was my goal. Having dieted aggressively I have not always prioritized fueling my rides, and as a result often performance has suffered. So in the last few months I have been working on my fueling strategies so that I can start to perform as well as continue to lose weight.
“Athletes involved in moderate and high-volume training need greater amounts of carbohydrate and protein in their diet to meet micronutrient needs” (5)
I'm going to break things down into each macronutrient and discuss each. The points I make are based on my experience, my take on the research and my discussions with my dietician, they are not infallible. Also the advice given is general, diet needs to be individual to the athlete.
Not many gels in those pockets....
Carbohydrates
Carbs are the most important macronutrient for endurance exercise as they are the main source of energy (1,3). Carbohydrates are stored as glycogen which the body uses to create energy to perform work. I am of the opinion most cyclists in training do not consume enough carbohydrates. If you are anything like I used to be, you’ll eat before doing a standard ride (2hrs or so) sometimes but not take any food with you when you ride. For longer rides (4+ hours) you might bring a bar or 2 or a couple of gels (at ~25g carbs each), maybe a bottle of sports mix and that’s it.
If you are this type of person, you're not fueling your performance. Your inability to perform in training and your lack of ability to recover may stem from the lack of fuel, and the longer we ride for, the more important carbohydrates become. Studies have shown they significantly improve performance especially beyond the hour mark (10). Carbohydrates are especially essential for high intensity exercise (1,2,3). The pathway for fat metabolism just doesn't provide energy fast enough to facilitate high intensity exercise.
To illustrate the point about not eating enough, consider this. 4 hours of riding at a solid 200 watts burns around the equivalent of roughly 750g carbs in energy(not far off 200g/hr). Energy burned while riding equation in appendix.
How much can we consume?
While the older research talked about carb oxidation (how quickly we can get it into the body and use it) of around 60g/h (6) the more recent research is suggesting up to double that to 120g/h and possibly more (11,12). An important factor for the ingestion is we need a combination of glucose (the most basic sugar) and fructose (fruit sugar) which have been shown to increase uptake (or oxidization) more than just one source (7,8,9,12). This ratio has been reported previously as 0.5:1 but it appears 1:1 Fructose:glucose is effective (12). Regular sucrose (white, sugar, brown sugar, etc) already has a 1:1 Fructose:glucose ratio, so don’t be confused by powders claiming they are special by having this magical ratio! Additionally, research on high molecular weight and thus a lower osmolality of the starch (basically, the number of molecules matters) may help with absorption, which is where maltodextrin and other large carbohydrate molecules come in which you will find in a lot of sports drinks. (11)
How do we apply all this? Let’s use an example of what I commonly see on ~4 hr rides: 2 bars (25g of carbs each), a bottle of sports drink (25g) and a gel (20g) would mean you have consumed 100g of carbs 25g of carbs an hour - a bit over 10% of what you have burned. It is just not enough fuel. My aim, at the moment, is to replenish (even on a training ride) 50% of the calories I burn while I ride in the form of carbs. So this means on a 4h ride at 200W (a solid endurance ride for me) I will aim for around 375g of carbs.
Fueling during recovery
Research currently suggests 1.2 g of carbohydrate/kg/hour for the first four hours into recovery (5). This is a much longer window than most people think, who try to consume all their carbs in a meal straight away. It appears using that 4hr window to consistently graze on carbohydrates is more effective than a one off large dose of carbohydrates if we want to refuel. Since we know we can only absorb a certain amount of carbohydrates, turning it into usable glycogen, it is likely a large meal containing more than this may either be stored as fat or expelled as waste.
Let’s use our 4 hour ride example above, and say we’ve taken our own advice and have bumped the carbs up to 350g consumed over the course of the ride, for 750g worth of carbs in energy burned. That leaves us 400g to go to fully refuel, and given the 1.2g/kg/hr for a 75 kg person, you are looking at roughly 100g/hr so the full 4 hours to fully replenish glycogen.
However, we don’t necessarily need to go out and smash through a bunch of bowls of plain pasta. There will be fats and proteins consumed in a balanced meal, which will also replenish energy stores. Normal lunches and dinners can also form a part of this refueling strategy - my personal practical aim is a meal on returning home of approximately 100g of carbs, then another meal an hour or 2 later with a similar amount of carbs in it.
Are we Chronically under-fueled?
If we look at the above numbers and how much we may need to eat, I don’t think a lot of cyclists fuel well enough. If we aren’t following the above recommendations for fueling and refuelling we may not be getting required glycogen to muscles and liver. Each time we ride, stores may be dropping and not recovering this over time, could be weeks or even months, may begin to deplete ourselves of our glycogen stored (19). Once this happens we will not be able to perform. Fasting status has an impact on performance - if we are fasted (low glycogen stores) you will perform worse (10).
To summarize, we burn a lot of energy if riding at even a moderate pace, and we should be looking at eating more on the bike (I would say minimum 60-80g of carbs/hr). We need to refuel smartly, not just one big meal but spread out.
Something Jesse and I have been playing with is adding brown sugar to sports drinks. Brown sugar is made up mostly of sucrose which is 50% glucose and 50% fructose, the ideal ratio. I add 50g of this to a bottle with Staminade mix in it to have a 70-80g carbohydrate total, making it easier to stay on-top of carb intake.. I don’t think it tastes too bad and I find it easy to stomach.
The lads, probably chatting about protein.
Protein
For protein the general consensus is around 1.8g/kg of bodyweight should be consumed daily for endurance athletes training regularly (13). For a 70kg athlete this is around 125g of protein. More protein than this may be needed in times of weight loss or when specifically trying to build muscle (13). With insufficient protein an athlete will have protein catabolism (the breakdown of proteins) and slower recovery. Over time, this may lead to muscle wasting, injuries, illness, and training intolerance (14).
A dose of protein should be in the 20-40g range (the upper end for after exercise bouts or older athletes) (13,17). The protein also needs to be a high-quality protein, this means they are highly digestible and have a good balance of amino acids (the building blocks in the body). The best dietary sources of high quality protein are lean meats, milk and eggs (17) These are abundant in all the amino acids and are readily digestible. Another option is whey based supplements.
Vegetarians and vegans may have more difficulty ingesting high quality proteins. Often plant based protein sources may be deficient in some amino acids. I won’t go into detail on this but it is important that vegans get their protein in from a number of sources (legumes, soy, wheat, rice etc) to allow for deficiencies in amino acids. If looking at sources for protein for vegans it appears rice (15) and pea (16) have performed the best in studies looking at replacements for animal based products. When looking at a supplement a mix of pea and brown rice proteins is what I would be getting as they are complementary*. It also might be a good idea to aim for a little higher protein amounts to ensure you are getting in enough - around 2g/kg should suffice.
*with all supplements there is always a risk of contamination. You should take steps to minimize the risk like having batch tested supplements and use supplements on informed choice.
Fats
The role of fat is a complex one. There’s a lot of hype around things like the Ketogenic diet (which aims to reduce carbs to almost zero) but the simple reality is that for athletes in high intensity sports like cycling, fats simply don’t provide enough energy at a fast enough rate to sustain performance (18). However, fats are essential in your diet and cutting out l fat is not ideal.Good fats to include in your diet are things like nuts, some oils and avocado. As always, a healthy balanced diet will likely take care of all of this, and there’s certainly no reason to be afraid of a little fat in your diet!
FAQ
I can't eat while riding. To those that think they cannot eat while riding I will make 2 points. 1. This is trainable, you will get better at it the more you do it. 2. You may need to experiment to find the foods that work for you.
Where do fasted rides fit in? This is beyond the scope of this article but to briefly touch on it. There are potentially some benefits in endurance adaptations, but it may lead to more fatigue and worse performance in those sessions. I don’t believe being fat adapted is performance enhancing for high intensity events (racing). Ultra-endurance events are different. There has been no consistent evidence that the train low, race high theory improves performance (18). If you do want to do some fasted rides, or your rides start too early for breakfast and are short it’s probably ok, but try to limit these to low intensity rides, and only a couple of times per week. Fueling for high intensity sessions is key.
Timing of protein. For the athlete above I would try to get their 125g of protein in over 4-5 doses over the day. This is supported by the research which recommends breaking up doses at least every 3-4 hours (13). For an acute dose post exercise, despite popular belief, there isn’t a specific window although the anabolic (muscle building) effect likely diminishes with increasing time post exercise (13). Acute protein doses should have a higher relative leucine (an essential amino-acid, aim for ~6 grams across the day) content, in addition to a balanced array of the essential amino acids (EAAs) (13).
This has been a long article, so thanks for reading and if you got to here well done! As always if you want more advice, or are looking for a personalised training program feel free to email us at coaching@nero.bike.
Appendix Calories burned equation:
Power(Watts) = energy(Joules) / time(seconds)
1 Joule = 0.238902957619 calories
Efficiency cycling humans is between 20-25% (1j to the pedals is roughly 4-5j of work for the body).
If we assume 24% efficiency then conveniently the joule to calories equations cancel out so we assume that measured joules = real calories burned (which most good training platforms such as today’s plan have the metric of measured joules)
With a bit of rearranging of the original equation we can also have the equation
energy (kcal) = avg power (Watts) X duration (hours) X 3.6)
You might be wondering where that 3.6 came from. It’s simply an adjust for time and the factor of 1000 reduction to get from cal to kcal (60 seconds/minute * 60 minutes/hour * 1/1000 cal/kcal = 3.6).
1g of Carbohydrates = 4 Calories
References
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16. Babault N, Paizis C, Deley G, Guerin-Deremaux L, Saniez MH, Lefranc-Millot C, Allaert FA. Pea proteins oral supplementation promotes muscle thickness gains during resistance training: a double-blind, randomized, placebo-controlled clinical trial vs. whey protein. J Int Soc Sports Nutr. 2015;12(1):3.
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