I have made it no secret that I am very impressed with Nishiki brand sushi rice, prepared with sugar while fluffing, as the ultimate ride fuel. I have been looking for a better way to carry it with me on rides though.
I had an epiphany tonight, and decided to try grinding up the cooked rice, as grinding up the dry rice and then cooking it didn't work at all. I think this is going to work. I'll use a Hammer flask to hold the gel, just like Hammer Perpetuem - a product I won't use because it contains carnosine, a snake oil from the Area 51 of nutrition.
Carnosine might work, it might work great, it might also leave your body in ruins. I'm not getting paid a boat load of money to ride, so I'd like to stick to food that's proven beneficial to mankind for a few tens of thousands of years.
I used a wand mixer and my stainless steel Starbucks cup, but think something larger is needed. I also was using 5-day old refrigerated rice, which was a bit dry and hard. In my next attempt I will grind the rice while it is still warm and soft.
I may add a little more sugar, and even try adding some coffee, as the rice I used today, while it tastes nice and sweet eating whole, tasted a lot more earthy once ground and in the flask. A good thing maybe, as on long events all those commercial ride fuels start to taste sickly sweet.
If you want to add a powerful, natural antioxidant to this rice, add acai powder or juice. I experimented with it quite a bit a few years ago, and it works. It does tend to bring on sudden cramps when you run out of it, but since it's been used for thousands of years by natives in the Amazon, I think it's fundamentally safe. The cramping may well be due to the increidble levels of strength and energy it supports. Wow, what a ride!
I have two goals in making my own ride fuel. The 1st, is to reduce its cost. Second, a friend challenged me a couple of years ago to find natural foods to use as ride fuel, as he was increasingly concerned with dangerous ingredients, mystery ingredients, and outrageous lies of all sorts made by sports nutrition companies. ( EFS, for example, claims sucrose (table sugar) and dextrose, a synonym for glucose, are complex carbs. A flat out outrageous lie, as a 10 second Google Safari will reveal.)
I could, of course, just order a 50lb bag of maltodextrin from GPC in Mollines, Iowa, but there's nothing natural about corn flour that's been treated with enzymes and then cooked in high heat to break the complex carbs down into something technically not sugar, but very close. As we've seen with HFCS, these seemingly harmless chemical changes can have some nasty and unexpected side-effects.
For pre-ride fueling and on ride fueling, the rice allows me to go as hard as I like and never get indigestion, cramps, or bloating. Pretty great stuff!
Like many amateur athletes, when I took up cycling again 3 years ago after a long hiatus, I came to the sport with a lot of poorly-informed ideas about sports nutrition, and specifically, what the characteristics of optimal sports carbohydrates were, and how they are digested and used in the human body.
While omitting oceans of details in writing this, I will attempt to illuminate the most relevant points, while avoiding overwhelming you with detail. This often-promised post has taken so long to write, because this is such a difficult balancing act to achieve.
Before we go any further, lets make this page a lot more readable and agree on an abbreviation for saccharides, or glucose units. Lets abbreviate that as GU.
Length and Branching of Carbohydrates
If you're old enough to consume carbohydrate as alcohol, then your mother probably warned you to avoid sugar, and stick to complex carbs like bread, rice, pasta, and potato. That advice is well-intentioned, but misinformed (So long as you're burning that sugar. Otherwise stay away from fructose and sucrose). All carbohydrate ultimately is digested into simple sugars, and then into the stuff that's flowing through your veins - glucose.
There is no mechanism in digestion to absorb any carbohydrate other than glucose into the bloodstream. ALL carbohydrate is reduced to glucose for digestion. Carbohydrate that cannot be reduced to glucose for absorption by the small intestine is either fermented by bacteria in the large intestine, producing heat and gas, or is excreted as waste.
The rate at which this occurs, if it occurs at all, is measured by the glycemic index (GI), and is NOT determined by the size of the glucose polymer you are ingesting, simple or complex. I say if at all, because cellulose and inulin, and for some people, lactose, is not digestible.
Glycemic Index of common sugars
It's also important to understand that your sense of sweetness doesn't indicate anything useful about how suitable a particular kind of carb is for sports nutrition. Fructose tastes 2X as sweet as glucose, but takes over 15X as long to digest. This difference in sweetness explains high-fructose corn syrup, which until converted, is almost entirely glucose. Other carbs that taste rather sweet, like the inulin in bananas, cannot be digested by humans, and serve only to feed bacteria in your large intestine, creating gas and bloating.
So sweetness - a subjective sensory phenomenon - is NOT correlated with speed of digestion, as the GI of various sugars makes obvious, but does indicate when the GU count of starch (the shortness of the glucose polymer) is getting down into sugar's range, as starches, and high-GU maltodextrins, are not sweet. An interesting exception is Asian people have been eating rice for so long that their saliva breaks down rice starch in the mouth so fast it tastes sweet to them, and them only.
Fruit trees have maximized their inducement to animals to eat their fruit, and thereby spread their seeds, by producing the maximum amount of sweetness for the minimum investment in energy. If trees could walk, this wouldn't be necessary. A lot less energy is needed when "sweet" is 2-5X as great for the same amount of carbohydrate/energy.
The glycemic index of anything ingested is established by the simplest of tests. Healthy humans are fed the test food, and then have their blood glucose levels measured every 15 minutes, usually for 3 hours. You can easily perform you own glycemic index tests for the modest cost of a blood glucose tester. The result is a graph like this.
Venous and Capillary Blood Glucose levels after ingesting 5 different grains
The much lower peak, and longer tail of the left graph is the result of insulin's effect on skeletal muscle's rapid uptake and metabolism of blood glucose. In creating this graph pair, I took great care to insure the Y (vertical) axis were the same. By following the colored lines at 60 and 90 minutes you can get a feel for how dramatic these differences are.
Carbohydrates known as sugars are typically either mono or disaccharides, having 1, or 2 GUs respectively. There are also trisaccharides, with 3 GUs, which you need Bean-O to digest, oligosaccharides with 3-10 GUs, maltodextrins with 5-33 GUs, amylose with 300-3,000 GUs, glycogen with 30,000 GUs, and anylopectin with up to 2 million GUs. Plant starch is either amylose, or amylopectin. Here's a great discussion of polysaccharides from Sacramento City College.
Amalyose: a linear chain of glucose molecules
Glycogen, containing ~ 30,000 GUs branched every 8-12 units. A masterpiece.
Liver glycogen's branching is novel in that it has more branches near
the core, and fewer, larger branches on the periphery, reminding us that
these are physical structures that must fit neatly in 3 dimensions.
Amylopectin's massive 2 million GUs branched every 15-30 units. Contrary to proponents of the Paleo Diet, humans are uniquely adapted among primates to digest starches, so starch has been part of the human diet long enough to change our genetics.
Glycogen is often referred to as "animal starch" because it has a very similar chemical structure to the huge amylopectin glucose polymer in plants. It's "shorter", having fewer GUs, but is more branched, and that branching turns out to be the 800lb gorilla in the room sports nutrition mfgs don't seem to want to discuss.
Human Metabolism of Carbohydrates
Digestion of carbohydrates takes place in the mouth, duodenum, and about the first 40cm of the small intestine. Except for alcohol, the stomach is incapable of absorbing anything, doesn't have enough surface area even if it tried, and for the most part, is a special-purpose organ for breaking down proteins - especially meats - and its polar opposite Ph balance arrests digestion begun in the mouth.
Polymers of carbohydrate present in starch and complex sugars are first attacked by salivary amylase in the mouth. Interestingly, the sweetness of certain grains, like waxy rice, is due to some of the starch being broken down into small enough polymers - nominally glucose - to be perceived as sweet.
Maltodextrin commonly used in sports nutrition have a DE of 9, where glucose is 100, so a GU of 100/9, or ~ 11. It is fairly easy to reduce that to glucose and maltose. The same is true for waxy rice's 3D "grape cluster" structure getting cleaved off the "vine" and attacked.
This brings up an important point. While many carbohydrates, such as starch, fructose, lactose, etc, have their own dedicated amylase that acts only on them, all amylase fall into 1 of 2 kinds. One kind attacks ONLY the branches of glucose polymers, and the other attacks ONLY the ends.
There isn't much for the latter to do with something long and unbranched, like amylose, which accounts for its much lower GI. Both amylases attack at random locations, but in highly branched polymers, breaking a single branch connection exposes dozens of ends. By contrast, breaking a linear polymer exposes only 2 ends.
This simple idea is why branching is much more important than polymer length in creating the high GI carbohydrates for optimal sports performance. (as a point of interest, the very best high explosives have this same, very complex branching structure, but with many oxygen atoms bound into the molecule, so that both the fuel and oxidizer are present in close proximity in explosives)
Intestinal villi's brush border has a surface area equal to a small 2 bdrm apt
Let's come at this conclusion from the other end. Since all carbohydrate digestion finally reduces glucose polymers to single glucose molecules, why not just ingest glucose. How can you beat that?
Well, first, you can beat that. Maltose, a disaccharide, has a GI of 105, higher than glucose's reference GI of 100. So do certain types of rice, potato, and dates, where certain varieties approach a GI of 140. This clearly indicates that the intestinal brush border is capable of simultaneously reducing glucose polymers, and absorbing the resulting glucose monomers.
(Dedicated amylase such as sucrase, and invertase, go unused if no sucrose is available, so adding sucrose to denser fuels, whose digestion occurs simultaneously, increases the total digestion rate, and that strategy is used by almost all commercial ride fuels, but these are supplements, not replacements for denser fuels)
For athletes, the real answer to why you can beat pure glucose is temperature. Cold, dense air increases VO2max, but minimizes electrolyte demands, so Gatorade's combined electrolyte, hydration, fuel strategy fails, and only denser fuels can provide the extra energy to fully utilize available oxygen. Heat is more insidious. It's a frontal assault on you ability to digest carbs, so optimal fuels are imperative.
Sugars are NOT very energy dense. Imagine how much straw you'd have to burn to keep warm in a really cold climate. Straw burns very fast, but it doesn't produce much heat. You could also burn balsa wood, spruce, pine, douglas fir, fruit wood, or oak. You still might not care what you burn if there were no limits to the bulk/volume of fuel you could burn, but there are. Think of your carb digestion rate as the size of the hole in the wall you have to pull fuel through. Denser fuel is obviously better, especially since HEAT shrinks the size of the hole.
Sugar, like salt, increases osmotic pressure (as much as 300 psi) as more of it is added to liquids like Gatorade. Increase the strength to get more fuel, and the osmotic pressure becomes so great your small intestine can no longer pull salt and glucose into your blood, so it passes undigested into your colon, where bacteria are eagerly awaiting their next meal. The by-product of that bacterial digestion is gas, and its attendant bloating. This limits the amount of sugar to about a 6% solution - exactly what Gatorade has.
When it gets hot, things go from bad to worse fast, because your body has to keep your core cool, and to do that it has to open your capillaries and start devoting a lot of small intestinal surface area to absorbing water to support sweating. This has 3 negative impacts.
First, it starves your digestive tract for blood, so even if your intestine hasn't completely shut down, there isn't enough blood to properly absorb all available glucose from the intestine.
Second, at some point, your small intestine can no longer absorb enough water to support sweating. Not to worry, your large intestine (colon) is not only ready to absorb more water, it's actually more efficient at it, BUT, when processing so much water, there isn't much time for carbohydrate digestion and absorption while transitioning through the small intestine. Any carbs that get past your small intestine, feed bacteria in your colon, which will ferment them, but are downstream of the point where they are of any use to you.
Third, you need sodium, usually from salt (sodium chloride) or sodium citrate, to unlock any and all transport sites in your small intestine so glucose can be transported into your blood. While this does not consume sodium, sweating does, and in large quantities on hot days. Glucose, wrested from long-chain polysaccharides by the action of amylase, ends up useless without adequate sodium, and ends up downstream in the colon, supporting fermentation with its attendant gas and bloating.
Initially, you can dilute your Gatorade mix, which is what I do, but in doing so, you have to add back electrolytes and carbs to make up for the dilution. There are lots of good electrolyte solutions out there, but that doesn't help make up for the lost carbs.
(With intense sweating, only salt and pure water will prevent gas and bloating, as carb digestion is completely shut down. The body's water absorption rate is the limiting factor for sports performance in intense heat, and that is very dependent on maintaining adequate sodium levels)
What's needed to prevent glycogen depletion is a denser fuel with a much lower osmotic pressure than sugar. Say hello to starch, or some derivative of it, like maltodextrin, with a GI of 105. While salt greatly enhances the rate of water absorption, with intense heat, carbs have to be consumed at 75% of max HR or less to reduce sweating. Salt, water, then food.
Now knowing what you do about the structure of carbohydrates, you'll be looking for a carbohydrate with a structure like liver or muscle glycogen. Highly branched, and very densely packed. Obviously, amylopectin meets this criteria, and accounts for the large difference in GIs amongst rice varieties with high and low percentages of amylose.
Maltodextrin squeaks by because it has ~ 11GUs, and a much lower osmotic pressure than sugar. It doesn't leave much for the branch-breaking amylase to do though, relying solely on linear polymer reduction by end-breaking amylase. I'm guessing, but I think all that type-specific, unemployed amylase becomes part of the problem.
High amylose starch is necessarily low amylopectin. All starch is one or the other. The former has GIs in the 60s, and the latter in the high 80s. In fact, short-grain waxy rice has zero, or very near zero amylose, and certain varieties have a GI of over 130. (item #293)
Relatively small amounts of fuels this dense, supplemented with small amounts of sucrose and fructose to make max use of all types of amylose, will produce as much glucose as a balanced attack by all varieties of human amylase can sustain, and the intestinal brush border can absorb. It can do so with NO osmotic pressure problems. This is like burning 400 yr old English Oak, with straw and pine sawdust blown into a fire mixed with compressed air. WOOSH!!!
Glycemic Index and Insulin Index of Selected Rices
We're not quite done with our story though. Until now this discussion has been entirely about how to maximize the sustained rate at which we can get glucose into the bloodstream, but this is only half of the problem. We still need to get that glucose moved through muscle cells' outer membrane, and into the cell's mitochondria. Without the action of the hormone insulin, all that glucose is locked out of the muscle, and essentially worthless, so how can we maximize an insulin response to use a maximized glucose delivery? Choose foods that solve both halves of this problem.
Look back up to the two GI graphs. One for venous, and one for capillary glucose. Remember the huge difference in those levels is due entirely to the effect of insulin on large skeletal muscles. Now look at the insulin index of Waxy rice above. Even though the GI of waxy rice is lower than Pelde white rice, the insulin index is a staggering 32 points higher! (we might also suspect that such a high level of insulin is lowering the observed GI by increasing the rate at which measurable glucose is being absorbed by either adipose tissues, or large skeletal muscles)
Have you ever had a 15-20 minute interval where your strength was super-human? We've all seen these displays by professional athletes. They're the stuff of legend. I'm speculating here, but I think those incredible moments of strength are due to a convergence of high blood glucose and high insulin levels. The pancreas does not release insulin on a continuous basis, but at approximately 6 minute intervals, or as short as 3 minute intervals in highly trained athletes. After this flood of insulin is released into the blood, it's monitored for depletion. For athletes, carbs that induce a larger release of insulin are better carbs.
In summary, looking at the GI of many foods, it seems clear to me that the gains made by sports nutrition companies in "predigesting" starch carbohydrate into shorter, linear glucose polymers (maltodextrin and brown rice syrup), has reached a plateau. It looks like the way forward is to find varieties of rice, or perhaps other starchy grains, which naturally have very high GIs, investigate their branching structures, and cross breed or genetically engineer "super fuels" - which may have GIs close to 150, and provoke intense insulin responses. Such a break-through is more likely to come from Monsanto than Hammer, as the research effort will surely be large and expensive.
Ironically, this investigation has already begun, but it's focused in the opposite direction - to find or create lower GI grains to address the obesity epidemic. The table above was taken from such a study. It may seem a frivolous endeavor to find a "super fuel", but imagine the benefit for infantry to have a fuel that will stave off glycogen depletion from sunrise to sunset on the longest day. It, of course, is also of great interest to those of us who compete against time and reason to find satisfaction and glory.
Lots of computer problems here this week, so not wanting to invite marauding hordes of malware into my life, I am tending to LOTS of system software issues at the moment.
What's on tap for next week though is really special. It's a presentation on the length and structure of carbohydrates. Carbohydrate glucose polymers go from a length of 1 (glucose) to a length of over 2 million (cotton, and some very special ride fuel). Shorter is better, right? That's what the people selling brown rice syrup and maltodextrin keep telling us. Are they wrong? If so, why?
Why isn't pure glucose the ultimate ride fuel? and how can anything have a glycemic index higher than pure glucose? Things worth knowing. I'll also explain the science behind the glycemic index, which is so much in the news these days, and deserves to be.
I know I've promised this before, but small libraries have been written on this subject, and it's the "science", bold or implied, behind millions of advertising dollars. All of this makes it very difficult to put in an intuitive presentation format. As my father used to say, "If it's worth doing, it's worth doing right". So be it.
Sac-A-tomatoes has been inundated with a very nasty flu bug the last 10 days, and I seem to have had a near-miss. Literally. I got hit. It's more like it's black, hooded, maliciousness slithered past me while I was hiding behind my shower curtain in the midnight hour, but shower curtains being porous and all, I still seemed to have gotten dosed a bit. Still hoping to get in a 75-miler this weekend, but DAMNED I hate being sick. Sensory deprivation with a twist of achy fever!
Hoping to ride today, and not knowing I would wake up in soaking wet sheets with a raging fever this AM, I went shopping last night and scored some of my favorite ride fuels. Some, like the Acai juice drinks, (recession-laced price cut in about half btw) are more for before and after the ride, and the chocolate is for anti-oxidants. (that's my story and I'm sticking to it!) From left to right in the picture...
Zola Acai with Blueberry Juice. Something new for me, it was about the same price as the Bolthouse drinks and may or may not have more Acai content. It is all organic and has a little Guarana' kicker with 24mg of caffeine. Weirdly, it also has some oil in it with 1,200mg of omega 3,6,9 fatty acids. Zola is from San Francisco, so it's blessed by the liberal Gods of planetary salvation. I gotta try spiking my Gatorade with some of this stuff to get some anti-oxidants with my ride fuels.
Bolthouse Do Brazil BomDia is a new division of the Bolthouse family from Bakersfield, Ca. I was half expecting a small matter ~ anti-matter explosion in political sub-space with them in such close proximity here - sort of like seating Bill Maher and Ann Coulter next to each other at a formal dinner! The Bolthouse family has been making juices for 3 generations from their home-grown veggies right there in beautiful downtown oil derreks-ville. I love all of their juices and find their carrot juice, in particular, to be earthy and flavorful, without the sticky sweetness of Odwalla's carrot juice.
Bolthouse does Acai in 3 or 4 different ways, and the Pomegranate is very good and perhaps even a bit higher in anti-oxidants than the Blueberry mix. I chugged the Blueberry bottle right after I took this shot (can you see the shaking of my addict's hand as my throat went dry with anticipation? :D ) It sent the flu troll siren-screaming from my presence, or so I hope.
Powerbar Energizer - Fruit Smoothie - is my favorite rocket fuel. It works before, during and after rides. It has actual fruit, including fig and strawberry, and contains fructose as well as maltodextrin. The strawberry at least has SOME anti-oxidants in it. For 100,000 years at least, man has eaten fruit for fast fuel carbs, and all bundled up with those carbs was nature's own gift of anti-oxidants. Perhaps Mother Nature has had a chat with the Power People. In any case, a step in the right direction in my opinion. It also has 100% of your RDA of B vitamins, so while that maltodextrin is sucking up vitamins when being digested, this bar keeps your boilers stoked and protected at the same time.
Powerbar Step 1 - Oatmeal Raisin - which surprisingly, has oatmeal and raisins in it. One of the things I like about Powerbars is the content of the bars actually changes with each flavor, so you can tailor your fuel to your body's unique requirements. Oatmeal is so soothing on the gut it will get you through the worst of IBS, or in my case, the best of diverticulitis. Both Powerbars also have substantial amounts of protein in them.
Gatorade - Frost - mixed from powder at half strength, it allows me to dilute the sugar, and thereby control the osmotic pressure of Powerbars not quite dilute enough in the stomach. Failing dilution, any sugars in the stomach will actually pull fluids out of the stomach lining and make digestion pretty much impossible. Worst case the dilution results in an extra "nature break" or two, but will not leave you in gastric hell. As temps rise, and blood flow is diverted to the surface of the skin to cool your core, this dilution becomes much more important, as digestion suffers greatly. (missed the class photo here due to scheduling conflicts with the football team)
Hershey bittersweet chocolate bar. It's all about the anti-oxidants! That's still my story. Notice how tenaciously I'm sticking to it? :D It makes me thirsty for still more skim milk after rides, as long as I don't overdo it.
To offer a little balance, I should mention what I think doesn't work.
Cliff Bars - the whole grains take far too long to digest and will eventually pass through the stomach and small intestine undigested and will putrefy. The disgusting sound of the word "putrefy" is a good cue as to the resulting gastronomicalmalestrome that will ensue. Even if eaten while waiting for the US debt to be paid off, it's use of inulin, a fiber attractive to food mfgs because of its creamy texture, which cannot be digested, but loves to ferment in your gut, puts it in the "don't even go there" category. If you find yourself reaching for this product, just lift your bike up, slam it down on your leg sharply, attempting to use your large chainring to flay all of the skin off your shin. Trust me, that would lead to less discomfort.
Cliff ShotBloks - which are mostly brown rice syrup. They are fine, but brown rice syrup is just too slow to digest to make good ride fuel. They would be OK when on a long break, or just before a long downhill like Mt Palomar, but then so would a couple of slices of pizza and a Coke. They come in many flavors, and some contain extra salt and some caffeine, and some both. They are sticky, are a mess on warm hands, and tend to slip out of your hands if you're sweating.
Anything coated in chocolate, because in warm weather the chocolate coating melts and is a mess. If you are on the go your hands are instantly slimed with chocolate, so even on a downhill they are off-limits unless you are fond of the "hey look mom, no hands" riding style when going downhill 55mph. I have worked out a system where my keys are tucked under the left leg of my shorts, and my Powerbars under my right leg. This is because I have found I can handle, open, eat and stuff the empty wrapper back under my right leg using my right hand - while switching hands to stuff the empty under my left short leg usually results in litter on the road. I have lost keys from every other thing/place/person I have ever used to hold them, EXCEPT my shorts. If I am found running around in public without my shorts on, my keys are going to be the least of my problems! The spandex and rubber thigh-grippers seal keys in place through climbs, teary-eyed descents, brutal cobblestone, and bone breaking falls. In 30+ years I have never lost a key tucked into my shorts. My keys are on a ring with a mini-Border's Books card. One swipe and the Emergency Responders will know who I am and that I have a 25% discount coupon waiting for me if I survive - always looking for motivation! :D (The reasoning behind the mini-swipe card from Borders is that it's ID that isn't obviously ID. God forbid, if you should fall prey to foul play, there's a good chance it will be left at the scene. Always carry a good form of photo ID on you with contact info)
The glass colander contains Earl Grey tea. When really wrecked from a ride my food of last resort, even when very nauseated, is very, very sweet tea. How sweet? As much sugar as I can make float! A recent study has reported that caffeine after hard rides is very effective at speeding the replacement of liver glycogen after the 2nd hour. All I know is it makes me feel half human again after brutal rides - at least for a hour or so. Rinse and repeat as needed.
