Cycling nutrition is a crucial aspect of any triathlete's training and racing plan. During a race, it's not practical to eat or drink during the swim, and, for many athletes, high calorie intake during the run can lead to stomach problems, including nausea and malabsorption. Thus, the bike leg is the prime time to take on calories—and an effective nutrition strategy on the bike can set you up for a good run.
Marcus Garand, registered dietician and director of sports nutrition for NYC Triathlon Consulting Services, says, "During a race, the cycling leg offers the best opportunity to ingest solid food and fluids, bars, gels and sports drinks. Nutrition and hydration during the cycling leg sets the stage for a strong run. On the other hand, inadequate nutrition and poor hydration on the bike can lead to dehydration, cramping and GI issues."
Yet, how do you know what, when and how much to take in? While every individual will have different needs, there are a few basic guidelines triathletes can follow to help ensure they give themselves the best possible opportunity for success on race day.
In general all athletes will need:
16 to 32 oz. of fluid per hour
Plus, 30 to 60 grams of carbohydrate per hour
Here is where it can get a bit tricky. According to Neal Henderson, director of sports science at the Boulder Center for Sports Medicine in Colorado, "At intensity, it is impossible to match your [fluid and calorie] intake to your body's expenditure. The body only has a finite capacity to absorb carbohydrates; thus, you can only take in so much before the body can't absorb any more. The result of over-intake of carbs is what leads to GI distress."
Therefore, at higher intensities you will eventually reach a breaking point at which you will either have to slow down or risk bonking. One way to determine how long you can maintain a given intensity is to use a power meter in your cycling training.
Henderson states, "By using a power meter and observing the kilojoules you expend, you can get a fairly accurate measure of calories you are burning." This is due to the fact that, while cycling, there is very close to a 1:1 ratio of calories needed to kilojoules expended.
If you don't have a power meter, you will have to do a bit of trial-and-error testing during your training. But you already know you will need somewhere between 16 and 32 ounces of fluid and 30 to 60 grams of carbs, so you have a ballpark to start with.
After taking this into account, consider that the higher your intensity the higher your caloric expenditure will be. However, this is where the trial and error comes in; you can take in too much. Thus, be conservative in your intake adjustments and don't try and empty the cupboard before every ride.
Here are a few nutrition tips for racing and long training rides:
Pack more gels and/or energy bars than you think you'll need. You may drop some or may have a craving for one over the other.
Try/test different fuel/hydration systems during training. If a system is hard to use or unreliable, you won't use it as frequently as you should.
Determine how much to carry and how much to get from aid stations. Depending upon what's being served on course, you will want to carry more or less food with you; however, note that most races feature well-stocked aid stations, so don't load yourself down unnecessarily.
Know what is at the aid stations and where they are located.
Base nutrition intake on time not on mile markers; set your watch to remind you to drink on schedule. Try to take in eight ounces every 15 minutes and close to one gel or half a bar per hour.
Mark your bottles accordingly so you know how much you're drinking. For example, measure out eight ounces and then mark 8 oz. increments on your bottles to help keep your nutrition plan on track.
Drink intermittently when your pace is steady.
Practice all nutrition and hydration strategies and techniques during training.
Jimmy Archer is a pro triathlete, coach, and freelance writer. During his career Jimmy has raced at all distances and formats of triathlon, competing for the U.S.A. on four national teams and finishing top 10 at five XTERRA world championships. You can visit his website at jimmyarcher.com.
The black magic of nutrition; it’s a mystical art. What should you eat? What should you drink? How much? When should I consume it?
Long gone are the days of factory-produced chocolate Powerbar logs and pouring salt and sugar packets in to water. We now have new high tech formulas, salt tablets, and people telling us to make sushi rice cakes. But among these new foods and ideas, what is best? How do we know? Dr. Stacy Sims has her own take on it: Put some numbers behind it. When in doubt, test, research, and test again.
So that’s what we did.
Dr. Sims is, for lack of a better title – a nutrition freak. She earned a BA from Purdue University, an MSc from Springfield College, and a doctorate from University of Otago. She was an exercise physiologist and nutrition scientist at Stanford University. If you want to get her talking, bring up thermoregulation, gastric emptying, or maximizing vasodilation and evaporative cooling (what we normal folks call ‘sweating’). On more than one occasion during our time together, I had to politely ask that she reduce her word choices from PhD… to master’s degree… an sometimes down to a 3rd grade level when I really glazed over.
You are probably familiar with Dr. Sims’ work without even realizing it. She has helped to create several existing sports nutrition products on the market, and acted as a nutrition consultant for the Garmin/Slipstream Pro Cycling Team, the USA BMX and women’s track Olympic teams, Team Tibco, Team Leopard-Trek, and many top triathletes. More recently, Dr. Sims sought to create her own nutrition company, along with two co-founders, Ben Capron (formerly of Specialized), and Paul Pillitteri. The name is simple: Osmo.
What is Osmo? To even start, you must understand that the name came from a few other words – osmosis, osmolality, and molality.
Let’s start at the beginning. First, we must understand the concept of solutes and solvents. Simply put, a solute is a substance that dissolves in a solvent. If you have a glass of water and drop in a teaspoon of sugar, the sugar is the solute and the water is the solvent. Osmosis is the movement of solvent molecules through a partially permeable membrane1. When two areas are segregated by such a semi-permeable membrane (i.e. intestinal tissue), they want to achieve equilibrium. So what happens? The solvent travels from the area of low concentration to the area of high concentration to even things out. This process works great, and is what makes the water you drink get absorbed into your body (thanks, osmosis!).
Osmolality is similar to molality, but only takes into account solutes that contribute to a solution's osmotic pressure2. Put more simply, Dr. Sims says that it’s determined by the amount of ‘active’ particles in a solution. In a sports drink, osmolality is primarily determined by the macronutrient content – carbohydrates, amino acids, and proteins – and to a lesser extent, the electrolytes and other fillers (colors, additional flavors, etc). In blood plasma, osmolality is determined by substances like sodium, potassium, chloride, bicarbonate, urea, amino acids, and glucose.
The concept behind Osmo Active is to optimize this fluid travel inside our intestines, so we can become better hydrated (or less dehydrated). They key, according to Sims, is as simple as making the concentration of the drink lower than that of the blood. She states that blood plasma osmolality is normally in the range of 285-290mOsm (milli-osmoles), assuming you are sufficiently hydrated. As such, we want our sports drinks to be below 280mOsm.
Had enough science? The punch line of all that mumbo-jumbo can be expressed in a single number – 3.2%. If there is one big secret to Osmo, that’s it. Osmo has a 3.2% solution, or 3.2 grams of carbohydrates per 100ml solution. This is also the source of a great debate – and the key differentiator between Osmo and most other drinks. What solution is appropriate? Here is a small sample of what’s on the market:
Osmo Active – 3.2%
Skratch Labs Exercise Hydration Mix – 4%
Gatorade (regular) – 6%
First Endurance EFS – 8%
Custom high-concentration mixes (Carbo Pro, bulk maltodextrin) – As high as you want
The higher percentage, the more ‘stuff’ is in the drink. According to Sims, most standard electrolyte drinks are in the range of about 330mOsm – significantly higher than that of our blood.
What happens if the drink is more concentrated than your blood? Dr. Sims says that you can still absorb it, but your intestines must first pull water away from your body (to dilute the solution) – so it can then be re-absorbed. This slows the whole operation, causing bloating and fluid sloshing – and reducing the amount of fluid that can be absorbed. In addition, we’re told that Osmo has a proprietary ratio of glucose to sucrose (which aid in fluid absorption), and uses sodium citrate rather than the usual sodium chloride (said to aid in fluid absorption and aerobic metabolism).
Testing
Rather than simply sending sample products to us, Osmo invited us to a formal test in Boulder, CO.
Several journalists and local athletes were scheduled for two days of testing in a hotel conference room. The protocol called for very controlled conditions:
Sunday 20 January, Please do the following:
1) 60 min spin at 50% of your max (think easy, easy recovery spin)
2) Immediately following that spin, please drink 8-10 oz non fat/ low fat chocolate milk, or OSMO Acute or Vega Recovery (If you are vegan). No other training please.
4) Record everything you eat and drink: time of day, what it was, how much (in enough detail that you can replicate each meal/snack exactly on the day before your second day of testing.)
5) Drink 0.18 oz of water per pound of body weight throughout the evening before bed.
6) SLEEP: this is important! Replicate the same bed and wake times for both testing sessions!
Monday 21 January-- NO EXERCISE UNTIL TESTING SESSION
1) Take your core temperature pill no earlier than 15 hours before testing, and no later than 6 hours before the test.
2) Eat your usual breakfast and record it per Sunday’s detail (you will have to have the exact same food and amounts on Wednesday morning).
3) Drink 0.18oz of water per pound of body weight throughout the morning.
4) NO CAFFEINE within 4 hours of testing. Please record amount and type of caffeine ingested (i.e. black drip coffee, espresso, yerba mate).
5) Consume your last bit of food 2 hours before testing (please record this as well; you will need to replicate this on Wednesday).
Tuesday 22 January:
PLEASE REPLICATE SUNDAY WITH REGARDS TO FOOD, SLEEP, AND TRAINING- 60MIN SPIN AT 50% ONLY WITH RECOVERY DRINK WITHIN 30 MINUTES OF FINISHING THE RIDE
Before each test, we first had to pee on a urine test strip and weigh ourselves:
The rides started with a 15 minute warmup, then a 60 minute effort at 70% FTP, and finally a 15 minute all-out time trial.
For one trial, we were to ingest Osmo Active plus solid or semi-solid food. The second trial was liquid or gel calories of our choosing (whatever we would normally use). Fluid and calorie intake were both standardized based on body weight.
The order of the trial was randomized with a coin flip; I was Osmo first and ‘normal’ second. My solid food of choice was Honey Stinger chews (pink lemonade, to be exact).
During the test, we were asked for our perceived exertion and perceived level of thermal comfort (essentially – “How hot do you feel?”). This was also measured objectively via the core temperature pill I’d swallowed, along with a very fun tool – a thermal imaging camera. Here is a very colorful version of me during the test:
The camera allows spot measurement of temperature. The darker or more blue you are, the cooler you are.
In addition to temperature, we also recorded heart rate and power output. I happened to be in the middle of some power meter testing, so we weren’t at a loss for data:
With my first test being Osmo Active plus Honey Stinger chews, I was able to pick what I wanted for the second test. I’m a fan of EFS Liquid Shot, so that’s what I used.
Test Results
Before I really dive in to the results, I must note that I wasn’t able to follow the protocol to a T. I had another product event already scheduled in Boulder that week (Stages Power), which involved a hard effort the day before my first Osmo test. What to do? Being the scientist that she is, Stacy made the right choice – that was also the painful one. Hard ride on Sunday, and a test on Monday? Well – that means you need to do some sort of hard effort on Tuesday, so you go in to Wednesday in the same condition. My first thought was something to the effect of, “Holy cow this is going to be a hard training week…” Upon further reflection, I’m actually glad it turned out that way. Given the high training time requirement of triathlon and frequent hard workouts, this seemed more representative of what we might normally do during a stressful mid-season week.
On a subjective level, I felt roughly the same on both days. I slept the same amount and ate similar foods.
What does that all mean?
-Core temperature pill: My temperature stayed lower with Osmo
-Body weight: I lost less weight with First Endurance
-Hydration (USg): I stayed more hydrated with Osmo
-Thermal imaging of skin temperature: My skin was cooler with Osmo.
This didn’t quite make sense to me. It’s clear that my temperature was cooler with Osmo, but I was confused on the weight and hydration. How did I lose more weight with Osmo, but stay better hydrated? According to Stacy, “Cooler skin temperatures across the OSMO 15 min TT indicates greater sweat rate and evaporative cooling. Greater fluid absorption occurred as indicated by the USg hydration status (both trials started euhydrated, the OSMO trial conclude with a USg indication of euyhydration (<1 a="" body="" br="" but="" conclude="" indicating="" less="" loss.="" loss="" lqcal="" mass="" slightly="" the="" trial="" usg="" water="" whereas="" with=""> In a nutshell, I had higher fluid throughput with Osmo. I was able to absorb more fluid, maintain more blood volume, sweat more, and stay cooler.
What about power output? This portion of the test was unfortunately limited due to something completely unforeseen – a non-adjustable magnetic trainer. I had a top gear of 53x12, and completely spun out the trainer before hitting my required wattage. We didn’t realize this until the time trial was already in-progress. The other trainer in the room was a fluid model with higher resistance, but was being ridden by another test subject at the time.
This being the case, I simply spun as fast as I could, and used the same trainer for both tests.
The numbers are striking. With my trainer limitation and non-standard training methods, I was curious to see if the other test subjects had similar results. Was my data bad? Was I just tired for the second test? Did I simply slack off and not spin fast enough?
Let’s look at the data for the entire group of 18 participants’ power files:
I’m not confident we can say that the data as perfect, as we were at the mercy of different power meters and head units. I was personally using both a Stages Power meter and a Powertap SL+, but other subjects had various Quarq, SRM, Powertap units – along with a slew of head units. I’m not aware of how each head unit was set up, nor if each rider set the zero offset before both tests (I did). In any case – even if the data happened to be exaggerated by a technology snafu (we don’t know either way) – the results are noteworthy.
This graph shows a compilation of core temperature and wattage for both the 60min steady state and 15min TT:
Where does this leave us? Based on the test results, it appears that Osmo Active works as advertised.
There is one (large) stone left unturned, however. How do we implement this strategy for long course triathlon racing? Also – how does Osmo differ from the other similar product on the market, Skratch Labs? Can we really implement this strategy that looks so good on-paper?
I posed these questions to Dr. Sims, both during the trials and in many subsequent emails. I expressed my concerns, and asked if she would be willing to create an Ironman nutrition plan for me – but only if I could provide the key limiters:
1. Aid station frequency and product availability
2. Equipment set up (number of bottles, location of bottles, number of jersey pockets, bento boxes, etc)
3. Special needs bags
4. The general amount of fuss I’m willing to deal with
After some thought, she agreed. In part two of this article, we’ll cover the details of the plan, along with my experience with Osmo so far. Also, we’ll hit on some of the more basic concerns – taste, price, and comparison to other products.
This is part-2 of our tech-and-review of Osmo nutrition. If you missed part one, it is located HERE.
The topic of nutrition and hydration is a complicated one. Ultimately, there are many ways to skin this cat, get to the same result, or whatever you want to call it. Of late, we’ve seen a lot of talk about moving to a lower concentration drink and eating real food. The problem – at least for long-course triathlon – is, how do we implement such a strategy? After all, aid stations don’t serve rice cakes, sandwiches, and diluted sports drink. We can carry some amount of food with us on our bikes, but I’d venture to say it’s nearly impossible to carry enough solid-food calories for a 112 mile bike ride – at least one that does NOT include any stops at the gas station to refill. Even if we can carry enough food, lugging around enough fluid would have a huge weight penalty.
I posed some of these challenges to Dr. Sims, who agreed that the answer isn’t easy. I asked her to create an Ironman-distance nutrition plan for me – one that had a specific set of limitations. As you can guess, her ‘perfect-world’ plan would include aid stations stocked with her drink, along with each participants’ favorite foods. At least for now – that’s not going to happen.
Before we dive in to the numbers and hour-by-hour plan, I want to address some issues and questions that came up from part 1 of the article. As an aside, I’m keeping my opinion out of it; I’ve had race success and failure on a variety of different nutrition plans. A lot of your questions are my questions, too. I will say that without a doubt, race nutrition has been one of my biggest struggles.
Is it ALL about osmolality?
While solution concentration is certainly a key part of the Osmo story, Stacy was very clear with me that it is not the only piece of the puzzle. More specifically, she makes an important distinction: Liquids – even those that contain calories – are not intended to be a source of calories. Huh?! Yes, you read correctly.
Dr. Sims says that Osmo contains calories simply as a by-product. It contains glucose and sucrose in a specific ratio – because this speeds fluid absorption (i.e. your body will take this solution in faster than plain water). It just so happens that there are some calories in there, too. If your brain came to a screeching halt there for a moment, don’t worry – you’re not alone.
Along these same lines, I asked about other types of sugars, namely fructose and maltodextrin. What’s the deal?
Fructose: I’ve heard fructose getting a bad rep over the past few years. We all know about high fructose corn syrup, and have slowly seen it vanish from many sports and health-related products. But what about plain ol’ fructose? This is the very long story made short, from Dr. Sims:
“Fructose (a.k.a. fruit sugar) is one of the monosaccharides (other two are glucose and galactose). It is a simple molecule and it is notorious for GI distress because first it has to be actively transported through the intestinal cell wall - then go into the hepatic portal vein to be delivered to the liver where it is then broken down into sub-parts for fuel.”
In simple terms, it requires more steps and time to break down than something like glucose. Easy enough.
Maltodextrin: This is an oligosaccharide, typically manufactured from corn (in the US, where corn is subsidized by the government), and is a very common ingredient in many modern processed foods. I’ve heard mixed reviews on its use for sports drinks; some nutritionists’ information suggests that it shouldn’t be consumed by folks with sensitive stomachs and certain food allergies. According to Dr. Sims, it is attractive on-paper, as it can be used to make a low osmolality drink mix. However, she warns that due to the large molecule size, it takes longer to break down, and tends to pull water from your body and into the intestines (the reverse of what we want).
Pass the salt, please
Aside from sugar, there is another key component to understand in a drink – electrolytes. What type, amount, and ratio are appropriate? Dr. Sims notes that Osmo is somewhat unique in that it uses sodium citrate, rather than the usual sodium chloride. She says that sodium chloride can be problematic for some people, causing GI distress in high amounts. In addition, sodium citrate is a cofactor for cellular respiration (the process of converting food in to usable energy).
Somewhat similar to the calorie content of Osmo, the sodium content is not intended to replace lost sodium – it is simply there to improve the absorption of the fluid. Dr. Sims argues that we ought to load up on sodium in the days leading up to a race; if we do that, large amounts of supplemental sodium should not be necessary during the event. As an aside, I find that somewhat funny, as a 24oz bottle of Osmo contains 480mg sodium – MUCH more than many off-the-shelf sports drinks.
Ironman Plan
If you’re like me, science class was hard to sit through. After all of the in-depth mumbo-jumbo, I wanted to learn some actual application.
In the past, I’ve always made a spreadsheet for every long-course race, detailing my hourly intake of fluid, calories, and electrolytes – for both the bike and run. I try to include enough wiggle room for race-day adjustment of temperature (i.e. if the day turns out to be hotter or colder than expected). I will follow the same outline here, minus the electrolytes. Why? According to Dr. Sims, the importance of excess sodium is greatly over-stated, and there is no definitive evidence that it wards off cramping. She argues that calcium intake is much more important, along with the ratio of total electrolytes we take in. In fact, she recommends taking peppermint Tums during the race – they are rich in calcium, act as a buffer, and the peppermint is supposed to settle your stomach.
I provided Stacy with the following limitations:
1. I can start the bike and run with Osmo, but I will NOT refill bottles (i.e. carry individual packages to mix with water on-course).
2. Begin the ride with two Specialized Purist 26 oz bottles on the frame, and two more in Special Needs. I’ve tried every hydration system under the sun, and always find myself going back to two bottles on the frame. It simply works for me. As a result, total potential Osmo for the bike = 104oz.
3. The real food must be reasonable. I can live with a bento box (gasp!), but I refuse to carry 10lbs of food that requires constant unwrapping and maintenance.
4. My normal two-piece race jersey has two pockets available, but I’d like to minimize their use.
5. I am willing to carry a hand bottle to start the run, and can get a new one at Special Needs, but again – no refilling along the way at aid stations. Total Osmo for run = 40 oz.
Here are the stats (fluid and food ranges provided by Dr. Sims):
Male, 77kg / 170lb
FLUID (BIKE AND RUN): 10ml/kg – 15ml/kg per hour For me: 770 – 1155ml per hour (26 – 39 oz)
FOOD CALORIES (BIKE): 3.5 – 4 calories (kcal) per kg per hour For me: 270 – 308 kcal per hour
FOOD CALORIES (RUN): 3 – 3.5 kcal per kg per hour For me: 231 – 270 kcal per hour
TOTAL BIKE KCAL: 270–308 from food + 114–175 from Osmo = 384 to 483kcal per hour
TOTAL RUN KCAL: 231–270 from food + 114–175 from Osmo = 345 to 445kcal per hour
The Plan:
On paper, it looks doable. Note that the inclusion of EFS Liquid Shot was my doing; Stacy would have recommended going the route of 100% solid or semi-solid food. I chose to do this for easy-of-carry, and ultimately to take away some chewing work.
As far as the hour-by-hour schedule, I always build flexibility in to this. Special Needs isn’t at exactly, mile 56 and 13 on every course. Sometimes you are going slower than expected; sometimes faster. On race day, I keep a mental tally of how I’m doing on the schedule. For example, if I’m not 50% done with my total bike intake by mile 56, I know that I have some catching up to do (but the idea of the schedule is to avoid this entirely).
Is this the exact schedule I’ll follow? I’m not sure. That’s why we test in training. Maybe I’ll vary the food type more; I chose what I did based on current preference and keeping the math easy. Maybe the order-of-intake will be slightly different. The idea is to think of as many caveats as possible ahead of time, so we’re prepared for the worst on race day.
I agreed to experiment with this plan for the season, but with no guarantees of a positive review later-on. Of course, my hope is that it does work out great – but real-world testing will tell the real tale.
Taste, Price, and Competition
How does Osmo Active taste? While this is always subjective, I like the taste. It is mild – especially considering how high the electrolyte content is. It isn’t something that I’d likely drink just sitting around, but during a hard workout, it is very palatable. I’ve tried both the orange and blackberry flavors, and like them both.
While we didn’t discuss the Preload and Acute Recovery products in-depth, they seem to have gotten mixed reviews on taste. The folks at Osmo recognized this, and reformulated both products at the beginning of the year. I have been using the revised Acute Recovery, but never tried the original. To me, I put it near the top-of-the-heap for powdered recovery drinks. It’s no chocolate milk (which I don’t drink due to the lactose content), but it’s much better than some of the other recovery drinks I’ve tried. I have not tried the new Preload yet, as it wasn’t ready in time for this article.
As you can see, Osmo recommends mixing Acute Recovery with water or almond milk. Being the non-conformist that I am, I’ve been illegally mixing with coconut milk.
The price of Osmo is – to me – the only argument I can find against it. A canister containing twenty 16-ounce servings will run you $20. That’s the same price as an equal serving of Skratch Labs Exercise Hydration Mix.
Speaking of Skratch (a product I like), more than one person has asked whether Osmo is the same thing. If you read the early reviews of Skratch product, you’ll see that Dr. Sims was involved in its development. Is this simply her own branded version of it? If not, what are the differences? At first glance, the nutrition label reveals that Osmo has a higher amount of sodium and potassium per serving. Take it for what you will, but Dr. Sims was not willing to comment directly on the topic. Rather, she sent me a list of what she considers to be the least-known value-adds of Osmo:
“Osmo uses a unique ratio of glucose-to-sucrose, based on controlled testing for GI distress. We use organic fruit - ironically there can be 'fillers' of maltodextrin and silicon dioxide in organic fruit as flow agents; I refused to use this kind of fruit, so we sourced organic dried fruit powder with no fillers or flow agents, and the farm is fair-trade for those powders, so we cannot source directly in the USA.
All the minerals and vitamins are pharmaceutical grade and GMO-gluten free (again, the vitamins can be plated to fructose that isn't guaranteed to be GF or GMO free). We also use non-'bone-char' sugar – yes, almost all the sugar in the USA is whitened/bleached by the charred bones of animals; we use Glory Bee sugar that is charcoal filtered with charred wood.”
Solid Food Soup
To close, I want to address the many questions about solid food interaction with liquid. On the surface, it seems to make sense that everything is going to mix together in our stomachs into a ‘soup’ of sorts. Does drink osmolality go out the window once you take a bite of that gas station apple pie?
Because I’m not a scientist, I’m going to quote Dr. Sims on this one (don’t blame the messenger – you asked for it).
“I get this question a lot! There is a rate limiting effect of macronutrients getting into the gut… again, osmolality isn't the gold standard of gastric emptying or fluid absorption, it is the composition of the fluid (primarily the carbohydrates). The body isn't linear and digestion is an interesting process.
Basically, the rate of gastric emptying is regulated such that isoenergtic amounts of carbohydrates, proteins, or fats are delivered to into the small intestines - the MOA of the body's ability to detect as yet unmetabolized energy from a variety of sources is still not understood, but it isn't the osmolality of the chyme (mixed up food and fluid) or the broken down meal nutrients that regulate the transfer of the mixed macronutrients into the intestines. What this does, in a physiological sense, is ensure a constant rate of energy delivery to the small intestines.
Fluid composition comes into play separate from the food ingested. Volume ingested and solutions with a carbohydrate concentration of ~3% or less (comprised of physiological relevant sugars sucrose and glucose) with sodium, rapidly exit the stomach into the intestines. The theory here is water absorption is a quicker action than macronutrients, thus fluid out perpetuates water absorption to aid in digestion/blood circulation/metabolic waste.
Digestion is complicated but the body does a really good job of "titrating" energy so that everything isn't dumped in to the intestines all at once. There are feedback receptors sensitive to carbohydrate, fat, protein, sodium, potassium etc... to allow small amounts of macronutrients to exit the stomach into the intestines little-by-little (to try to keep a steady stream of energy going). Fluid is different; absorption starts in the stomach and quickly leaves to the small intestines where 95% of water exchange takes place. When you mix food and fluid, the fluid still exits faster than the macronutrients (especially if it’s a solution of glucose+sodium). The 'soup' in the stomach isn't really a 'soup', more like hearty stew over a colander - some of it runs out quickly, other of it is caught until it gets mushed up and pushed through the holes.”
Athletes take advantage of on-course nutrition at IRONMAN Texas/Photo by Nils Nilsen
Racing IRONMAN has been compared to a rolling buffet. Here’s how to maximize your on-course options.
By Becky Simon, Bonk Breaker Registered Dietitian
A nutrition plan is just as essential to your race as having a plan that addresses pacing, exertion and your overall goals. Consistent fueling and hydrating is the backbone of training and racing. “You need calories, and lots of them. Bottom line, you can't do an IRONMAN on electrolytes and water,” explains professional athlete and world champion Mirinda “Rinny” Carfrae.
Unfortunately, there is no universal plan that works for every athlete. Moreover, there is no one plan that always works every time. The key to nailing nutrition is to train your body to tolerate your chosen fuel source, to fuel often and consistently and most of all, maintain your flexibility. “You hope that plan A works, but you need a plan B and even C,” Carfrae says. “A race can be won or lost based on your nutrition plan so you need to put it to the test and be ready to shift it as needed.”
There is no cookie-cutter solution to your race-day nutrition needs, but the guidelines below will support you in building your nutrition plan.
Fueling choices: What’s on the menu?
Choosing a combination of carbohydrates, such as combining glucose and fructose, increases carbohydrate oxidation rates by 20 to 50 percent. Translation: more fuel to your muscles and less sitting in your gut, which can cause gastrointestinal discomfort.
During training, build up your calorie intake until you find a range that works for you, and with a good mix of solid and liquid calories. Athletes need to find a balance of carrying fuel, stashing fuel in their special needs bag and relying on on-course nutrition. Training with on-course nutrition options is key, so you won’t shock your system come race day. For example, if you prefer to carry your nutrition with you, but happen to drop a Bonk Breaker Energy bar while adjusting your sunglasses, you can stick to your plan by picking up another bar at the next aid stations.
As Carfrae explained, you need a plan B and C in case plan A breaks down. Know what’s on course and train with it, whether you're planning to depend on it or use it as a back-up plan.
Show me the numbers: How much is enough?
Going into exercise, your body can store an average of 2,000 carbohydrate calories in the form of muscle and liver glycogen and glucose in your bloodstream. After about 60 to 90 minutes you burn through your carbohydrate stores and your body requires consistent fueling to avoid the dreaded “bonk.”
Top off your glycogen stores with 200 to 300 calories, 30 to 60 minutes before exercise. Eat a carbohydrate-rich snack that's easy on your stomach and that you’ve used in training. Some pre-exercise snacks ideas include toast with nut butter, a Bonk Breaker bar, a banana and yogurt or oatmeal with milk.
Your fueling needs increase as the duration of exercise exceeds two to three hours. For 70.3 and IRONMAN athletes, aim to consume 45 to 90 grams of carbohydrate (which comes out to 180 to 360 calories) per hour. During exercise, your body will oxidize about one carbohydrate gram per minute, even when large amounts of carbohydrates are ingested.
Timing: When should you fuel?
The trick is avoiding the bonk long before it happens. You may not feel hungry, but you still need to fuel. You can manage your carbohydrate load by fueling consistently and often.
Some athletes find fueling every 15 to 20 minutes is helpful, while others focus on consuming “x” amount of fuel by a specific time period or distance of the race. Research has found that cycling provides the best opportunity to ingest larger amounts of fluid and fuel, specifically solid nutrition. “I like to ‘front load’ my nutrition on the bike with solid calories. Bonk Breakers really settle my stomach and give me lasting fuel throughout the day,” says professional triathlete Beth Walsh.
Training doesn’t stop when your workout is done, so don’t forget to refuel immediately after exercise and maintain a healthy, balanced diet.
This article is sponsored by Bonk Breaker, the official energy bar of U.S. IRONMAN events. To find out more about the elite athletes behind the real-food bars, or to purchase bars, go to bonkbreaker.com.
Hello Hayley, Just a quick email to ask if you would be interested in a ‘mutual’ following on twitter. I am currently following you now and am awaiting for your follow-back. (#FYI I do RT’s ‘ANYTIME’ for all #Triathletes #Cyclists #UltraRunners #Marathoners #FitnessProfessionals who follow me on Twitter and have something important they want mentioned for support…Over 41K folks at your access.)
All the very best for the rest of 2013 & beyond Hayley. Look forward to hearing from you…
Before we dive in to the numbers and hour-by-hour plan, I want to address some issues and questions that came up from part 1 of the article. As an aside, I’m keeping my opinion out of it; I’ve had race success and failure on a variety of different nutrition plans. A lot of your questions are my questions, too. I will say that without a doubt, race nutrition has been one of my biggest struggles. 
Fructose: I’ve heard fructose getting a bad rep over the past few years. We all know about high fructose corn syrup, and have slowly seen it vanish from many sports and health-related products. But what about plain ol’ fructose? This is the very long story made short, from Dr. Sims:
Somewhat similar to the calorie content of Osmo, the sodium content is not intended to replace lost sodium – it is simply there to improve the absorption of the fluid. Dr. Sims argues that we ought to load up on sodium in the days leading up to a race; if we do that, large amounts of supplemental sodium should not be necessary during the event. As an aside, I find that somewhat funny, as a 24oz bottle of Osmo contains 480mg sodium – MUCH more than many off-the-shelf sports drinks.
On paper, it looks doable. Note that the inclusion of EFS Liquid Shot was my doing; Stacy would have recommended going the route of 100% solid or semi-solid food. I chose to do this for easy-of-carry, and ultimately to take away some chewing work. 
Taste, Price, and Competition
The price of Osmo is – to me – the only argument I can find against it. A canister containing twenty 16-ounce servings will run you $20. That’s the same price as an equal serving of Skratch Labs Exercise Hydration Mix. 
Because I’m not a scientist, I’m going to quote Dr. Sims on this one (don’t blame the messenger – you asked for it). 
From: Darin Armstrong #TeamLIVESTRONG
ReplyDeleteHello Hayley,
Just a quick email to ask if you would be interested in a ‘mutual’ following on twitter. I am currently following you now and am awaiting for your follow-back. (#FYI I do RT’s ‘ANYTIME’ for all #Triathletes #Cyclists #UltraRunners #Marathoners #FitnessProfessionals who follow me on Twitter and have something important they want mentioned for support…Over 41K folks at your access.)
All the very best for the rest of 2013 & beyond Hayley. Look forward to hearing from you…
Darin
twitter.com/DarinArmstrong
#TeamLIVESTRONG
Hope you got my mutual follow. Looking forward to #ing!
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