Refueling on the Run

By , SparkPeople Blogger
I am in the midst of training for a number of fall races which commences with the Chicago Rock N Roll 1/2 Marathon this Sunday and ends with the Las Vegas Rock N Roll 1/2 Marathon on December 5th. Throw in the Hood to Coast Relay at the end of this month, followed by the Victoria 1/2 Marathon in October, followed by the San Antonio Rock N Roll 1/2 Marathon in November and well, let's just say I have my fair share of training cut out for me. What started out as obtaining a simple medal in New Orleans in February has led me to register for five Rock N Roll events, not only to run with other SparkPeople members, but to achieve the coveted Rock Star Medal bestowed on a runner who completes five events in a calendar year.

As my long training runs have progressed from an hour a few months ago, to my last long run on Saturday, which was a tad short of three hours, I have had to depend on refueling sources during my runs to help keep my energy levels high.

Over the past several years, engineered refueling sources such as Clif Shot Bloks, Accelerade and Gu have become all the rage for runners, walkers, cyclists and most other endurance athletes for that matter. Just pick up any runner's magazine and you will see countless advertisements for these products. Not only do these products offer the endurance athlete convenience, but their primary purpose is to offer a healthy dose of carbohydrates in a small package. Some products even go so far as offering protein and electrolytes, such as sodium and potassium, in addition to the carbohydrates.

Just like every runner cannot wear the same running shoe, the same can be said for refueling sources. If you were to ask an experienced seasoned runner about Shot Bloks, Sports Jelly Beans or Gu, they may sneer at the mere silliness of engineered refueling products--after all, pretzels, Oreos, and even Skittles have been used for years by endurance athletes for refueling. And who can knock the cost, for just a few cents you can receive the same benefits that the so-called more expensive engineered foods offer, but at a fraction of the cost.

So you may be wondering if refueling is necessary for you as a runner?

Let me start by giving you a little background on why endurance runners need refueling sources on long runs and what they do to help us become more efficient runners.

The long run is the most important training run for an endurance runner. While speed work and hill work are important in the development of running economy, it's the long, slow distance run which allows our bodies to develop the glycogen stores within the muscles and liver, in addition to conserving the glycogen we currently have. When we are running at a moderate pace, the body utilizes approximately 50% of the energy it needs from glycogen, or stored glucose in the muscles and liver. When you begin to deplete your glycogen stores, your body becomes more dependent on glucose in the bloodstream to help fuel your run. Remember too, that your brain cells can only utilize carbohydrates for energy, so consuming this nutrient on your long runs will also help with mental stamina.

Think of these glycogen stores like a gas tank in your car. As you travel down the road your car uses the gas to get you to where you need to go. If you do not refuel when your gas light comes on, eventually you are going to run out of gas and you'll be left on the side of the road waiting for someone to bring you more fuel.

Well, same is true when you are doing an endurance run. The body can only store so much glycogen, regardless of the amount of training one does. While training can help make your gas tank (AKA glycogen stores) bigger, you can only increase the size so much. In other words, we can only store a limited supply of glycogen, therefore when we start to deplete the stored glycogen, this is where refueling becomes necessary. However, please note that you do not want to allow your glycogen stores to become too depleted before you start refueling or else you may bonk, also known as hitting the wall.The body cannot turn fat into energy at a fast enough rate therefore, without enough glucose to supply your muscles, you will have no choice but to stop running. This is why timing is of the essence.

Most individuals can get by on just water or an electrolyte drink for most runs under an hour. After that point you will want to look at refueling with food or a sports drink. According to Sports Registered Dietitian Nancy Clark, in her book, Nancy Clark's Sports Nutrition Guidebook, consuming 25g-60g of carbohydrates or roughly 100 calories to 250 calories PER hour during your run should suffice.

Although this may seem like a lot of calories, now is not the time to worry about consuming these additional calories. Your body needs the fuel to get you through your training so that you have the energy to complete your workout. With the average runner expending between 90-110 calories per mile, running for a good 10 miles and up will require you to consume these extra calories just to keep you from hitting the wall. I personally use engineered products on my runs and the biggest reason is, the convenience factor. I can pop three bags of Sports Jelly Beans in my SPIbelt and be on my way. Just know that these products whether Gu, Shot Bloks or Sports Jelly Beans require that you take water with them in order to speed absorption within the gut. So much sure you have access to water if you choose to use these products.

Check the label to determine how many grams of carbohydrates are in each serving of the refueling source you use so that you bring the appropriate amount with you on your training run.

The standard recommended time to start refueling is anywhere from 30-45 minutes into your run and then roughly every 15 minutes afterward. For example the Sports Jelly Beans contain roughly 24 grams of carbohydrates for each bag which means I start using them 40 minutes into my run and then I consume a few beans every 15 minutes until I am done with my run.

As with everything else with running, practice is essential in determining the best refueling source and timing for you. You want to be especially mindful of any side effects you may have with the products you have chosen.

Most endurance races supply their runners with a refueling source on the course, however, if the source being offered is not one you have practiced with, now is not the time. You want to stick with what you have used in your training runs.

In the future, if you want to use the same product so that you do not have to carry any with you during the race, contact the race director and see if he/she can tell you what product they plan to use. The earlier you start practicing, the better prepared you will be when it comes to your decision as to whether to stick with your own or try using the one the race will carry.

I will add that I have tried using the sports drinks such as Accelerade and Cytomax, but I did not fare well with these products as they gave me a terrible bout of runner's diarrhea. I have since learned that due to the high concentration of sugar and the quick gastric emptying of the liquid product, this can be a common issue for many runners. Once again, this is why you must practice with the product you plan to use.

Do you use an engineered refueling source such as Gu or Cytomax, and if so do you feel they help? Which one is your favorite? Would you be open to using regular food as a refueling source?

Resources: Nancy Clark's Guide to Sports Nutrition and Endurance Sports Nutrition by Suzanne Girard Eberle MS, RD

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TURKEYTRAX 7/17/2019
Squirt tubes of baby food (yogurt/banana or sweet potatoes/carrots) or protein bars generally get me thru a half marathon. Eat half at mile 6 or 7 & the other half at mile 10. Report
Thanks! Report
thanks. Report
Thanks! Great info! Report
I have tried many products but have found muscle milk, chocolate milk ad coconut water work best for me. On really hot days providing I'm running 10K+ I'll also include the sports jelly beans or salt tablets.
From time to time, my GI tract suffers on long runs. I do know that it is a result of introducing too much sugar too fast. I started blending a sweet potato puree together that I saw in Runner's World magazine. A couple ounces of sweet potato blended with peanut butter, honey and water or orange juice makes a clump of high energy fuel that's gentle on the stomach. I make it fluid enough to squeeze out of a 2 or 3 oz. travel container like GoToob. Report
I have found that it depends on what I'm doing (cycling or running), at what intensity and what the temperature is. I swear by Cytomax, in part because I found that with cycling it helped to clear the lactic acid out of my legs faster so I didn't die on hills. I've kept with it as part of my hydration/refueling for running because I know it doesn't upset my stomach like Gatorade and it's not super sweet. As for gel-type substances, for cycling I like Hammer gel; the product works for me and because I can carry it in a flask it is convenient to store in my jersey pocket. For running I prefer Gu. It's easy to know exactly how much I'm getting in one quick shot and then I can dispose of the packaging.

This is what works for me, but everyone needs to try different things to see what works best for them. I'm currently on my third hand-held hydration system trying to find my "perfect" solution! lol Report
Hammer products! I just completed a 70 mile bicycle ride in 105 degree heat. Without hammer products and about 24 cups of water, I wouldn't have completed the ride. @Stringi719 - for hydration, nothing beats water. The general rule that we use for our track days is for every 1 Gatorade you should drink 4 waters. As for carrying your water with you, a CamelBack is well worth it, but so are the belts. As with this article, you really just need to find what works for you, even if it means spending some money to experiment. :)

@MrsPattersons - you might consider the Hammer Gels - I can't stand the Goo products myself - they stick in the back of my throat. The Hammer Gel products go down much easier and I don't find myself reaching for water immediately after consumption. Hope that helps! Report
This blog is too important NOT to save. Thank you, Coach!!!! Report
in one race Gu saved me. Took me fourtyfive minutes to eat on package, but It kept me going. Report
I tried shot bloks just to know what they are like but not for endurance training yet. My father used gu as a mountain bike racer and seemed to like that and Cytomax products. I am not a fan of cytomax based on flavor and ingredients (guarana and artificial sweeteners) Report
I sure admire what you are doing. Best of luck, and thanks for the info. Bless you. Report
For runs over 10k I use sports jelly beans or Cliffs shot blocks. For hydration plus liquid refueling I have been using chocolate milk, muscle milk and organic coconut water and they all seem to work pretty well. Report
I prefer Gu Chomps over Sharkies if I'm going to nibble on really long runs. and E*Load Light Tangerine gels work for me although I find myself getting quite sticky in the summer heat. Just to change things up a bit, I'm going to try mixing E*Load Fly with my Gatorade for sipping on past 20 km to see if I can forestall some long run bonking over my next couple of training runs.

Something I look for in my fuel source is the sodium/potassium levels. In addition to easily digestable carb calories, I require extra salts to prevent muscle cramping in my calves. Report
Wow, great info. Just doing my first 5k race a week from Sunday, so once I start increasing mileage and training for my first 10k, I'll keep this in mind. Lots to think about, since I am a post-op gastric bypass patient. Can't drink for 1 hour after I eat, so the energy bars probably won't work for me. I'm not a fan of Gatorade (don't like the sugary taste), and I have to watch my sugar grams, or it will make me sick. Also can't eat anything with Xorbitol or Xylitol (sp?) because it gives me intestinal cramping. I will check with my gastroenterologist's nutritionist to see what options are available for me. Thanks, Nancy, for bringing up this important topic! Report
I like Gu for my longer runs and races. I hydrate along the way with Gatorade's G2, then use water while I'm taking a Gu. Seems to work well for me. Report
I ran my second 1/2 Marathon in June, I did 2 10 mile training runs with nothing but water (personal favorite). My DH suggested that a gu for the race would be appropiate (marathoner). I tried the gu during the race (unflavored) drank water with it and seemed to be a little peppier than normal. Of course, he said I should not really try something new during a race, but I had tried jellybeans, fruit roll-ups, granola bars, during long runs in the past, nothing seemed to bother my stomach, but I dont like sweet flavors in my mouth when running. I also dont like to chew when running, so the gu worked best. Report
Thanks so much for this great article!! Report
Used to be a fire fighter and hydrating is critical to survive the hot temps out there in heavy gear. Report
I swear by "Honey Stingers" for energy food: organic, exactly the right fast burning fuel/electrolytes for my needs, dee-licious! Report
Makes me think about blood-sugar levels now!

I'm not a runner; I just do the Grouse Grind (Vancouver, BC). If anyone knows of it, they know it's short but INTENSE; it is said that one burns 1000-1200 calories during the .5 - 1.5 hour hike.

Can I apply this information to the Grouse Grind? Report
i am experimenting with this as i train for my first half marathon. so far, i've tried the power bar gummy gels, and i couldn't run and chew those big things. tomorrow, i'm trying a GU. it's just trial and error, but i'll be prepared by the time the race is here! Report
I have been using Sport Beans this summer. Over the past winter I used GU. It has been so hot and humid this summer I feel that the Sport Beans are working better for me (giving me the added electrolytes). Plus, hot GU doesn't sounds very appealing! Once the air cools, I'll probably switch back to GU as the beans are a little harder to chew once it drops below freezing in the MidWest. Report
Chocolate Gu, chocolate mint when I can find it. I have also used accelgel & hammergel but I like gu because the packets are smaller so easier to fit more in the pocket of my hydration belt. I like sport beans but I personally can't chew anything while I'm running. Report
Thanks for the info! I just ran my first half marathon and I used GU chomps. They seemed to work the best for me and my stomach. The GU did not sit well with me and the jelly beans don't seem to give me quite as much energy. I generally only carry water with me and would like to start carrying Gatorade or Powerade. This is something I want to keep experimenting with, so I appreciate the suggestions! Report
I just hit my 5k goal, so this is perfect timing as I consider how to start training for longer runs. Thanks Nancy! And, thanks to all the commenters who offered up their favorite fuels. Report
I use Gu for any runs longer than an hour - and I ALWAYS carry water! Report
When I trained for the R n R Vegas last year, I trained with Cytomax because that was what they were offering through the race. I found it was a good alternative to water. I would switch between Shot Bloks with water, then next break drink Cytomax. Water sometimes gets too heavy on my stomach so switching between the two everyother break really helped to keep my energy up and my stomach under control. Thanks for such a great article! Report
Thank you for the article. I'll be running 10K this fall, so very good information. I have a silly question since this is a new teritory - do you stop and eat or you eat while you are running/jogging? Report
I love the sport jellybeans, they are my sugar of choice - they are super concentrated, and go down easy. I also found last half that swedish fish are just about as good (and cheaper).

I did find that when training for my last half, when I was running in the afternoons for my long run - a big breakfast did me fine. I did most of my long runs without fuel and did fine. Report
Gu can be messy - a learned art I discovered - not to be learned DURING A RACE - The chewy things get stuck in my teeth - I try to (if used) take a few every 30 minutes and then i am picking them out of my teeth with my tongue for the next two miles. Haven't found the perfect fuel - but i am working on it. Carb-Boom is next on the list as it is a natural fuel.

I find that the Cytomix is ok for my stomach and gatorade is not - trial and error!
I have tried GU before and it really seemed to help with stamina. Have'nt really tried other sources but may now that I've read all the great posts about the different products people use! Thank You everyone for putting in your 'two cents' so other Sparkers can read and learn about refueling for long distances! Report
When I was running (an injury forced me to stop at the beginning of the summer... while cleared to run again as of last week, the heat and lack of summer child care has me stalled still!), I so struggled with this. I am a calorie control FREAK. I have worked so DAM* hard to lose this weight, the idea of consuming calories while expending them breaks my heart and my head a little bit. I would run 2-3 hours on my long run days and not do anything to refuel. I once literally passed out, post run, waiting for my blood sugar to catch up. Since I still REALLY struggle with this, I had come up with an idea that would help me keep my calorie intake lower while keeping my blood sugar up... baby food squeezy pouches. They make these little pouches of squeezable applesauce (and other varieties, but applesauce is my favorite... or strawberry applesauce). They are about 50-70 calories depending on brand... I don't know... I still struggle with the calories in part... but it is easier for me when I the calories are low while sugars and nutrients are fairly high. Report
Thanks for a very informative article. I am just about to progress in my running "career" to the point where I will be running long enough for this to be an issue I have to address. I feel more knowledgeable now about the choices and options available.

Good luck with your fall running schedule! Report
I have tried the gels (GU and Hammer), sports beans, clif shots, and GU Chomps. So far my favorite are the GU Chomps because they are easy to chew and not quite as gooey and the Clif Shots. I want to start trying taking the mini Clif Bars (100 cals each) since they should be easy to carry and see how that goes, but for now I have pretty much stuck with the GU Chomps (they work good for me). Report
way to go! keep up the training! Report
thanks for he advice!! Report
Thanks for the great tips! Report
I don't like Gu and I think sports beans are pricey. Instead, I just eat regular jelly belly jelly beans (cheap and taste good, plus they have the sugar I need). Another thing I use for runs over 10 miles- candy corn! I don't know where I'd put it but I know some runners who have a small pb&j sandwich while running. Don't know if I can stomach real food though... Report
I've used Gu - only the vanilla. Everything else has played havoc with my gut. After my first marathon, I had a GI bleed and ended up requiring colonscopy afterwards - not a great experience. I did walk 20 miles and run the last 10K of the next marathon I did a month later (with my docs approval) and all went well that time around. Report
My problem with most of the regular foods I've tried was either portability (at my pace a marathon is a 5+ hour affair, so carting anything bigger than the pre-fab stuff can get bulky!) or dryness. I ended up liking Gu, the lemon flavor was a favorite (more tart than sweet), as was chocolate mint (regular chocolate was too thick but the mint tasted "cool" somehow). Most of the flavors were nasty-sweet to me, but those 2 worked. I take one every 4 miles or so.

One other thing your article should note - its not just your brain that needs carbs. Your body NEEDS carbs to metabolize fats. The wall is both brain and muscles saying "we've got too little fuel left that we can burn!" Think of the carb calories as lighter fluid for fat :-P Report
Great article! Thanks for the info, Nancy! Report
Nancy, I think this is an outstanding article, and I am so glad you mentioned Nancy Clarks book. Anyone who embark on the journey of healthier living should read it, to learn fundamentals of nutrition. She also have a book specifically aimed at nutrition for marathoners. I think anyone who runs (or bikes for that matter) long distances could benefit from reading both of her books.

One of the things that changed my fueling strategy was when I realized your body is like a wood burning stow. You need to fuel it all the time ... just add a little fuel at the time.

If you ask 4 runners for their fuel preference - you will get 6 different answers and you WILL need to experiment with things to find out what works for YOU. However, in general - I stay away from anything ending in -ose, unless it is natural (i.e. fruit). - I primarily use maltodextrin as my carb source. If I do runs up to about 10 ish miles - I will use maltodextrin and electrolytes and if I go above - I will use a(n all natural) commercial brand that includes maltodextrin, soy protein, electrolyte mix during the race. Some of their products are vegan certified and kosher certified.

Re CAMELBAK's I happen to like the camelbak(r) - I regularly run about 9 miles home from work, and I have a Camelbak for hydration, and I can carry my wallet, and cell phone in the pocket. Report
water, granola bars, cashews are great... no engineered fuels for me. Report
I really like the Cliff shot bloks but the sugar usually ends up leaving me with a crash in about 6 miles. I don't like the high/crash sugar cycle I get with a lot of engineered products.
I've had my best luck with tangerines or clementines: they are cheap, compact, organic, come in a biodegradable wrapper, relatively easy to unwrap (unlike power bars), and I can occupy my mind for about a mile at a time (very key on the 20+ mile runs). Report
My mid-run booster of choice while running is Gu in chocolate flavor. While training for the 2010 Dick's Sporting Goods Marathon in Pitt, I found this flavor and brand to be the only thing that worked for me. My system (during training) was running with my CamelBak (52 oz.) full of water and taking a chocolate Gu every six miles. This proved to be an amazing way to keep my system fueled.

I tried Clif gels and PowerBar gummies, but neither of these seemed to work well. Clif gels made my stomach cramp repeatedly, and PowerBar gummies took longer to chew and did not give me a real boost.

For anyone training or considering training for a race, I encourage you to, upon registration, thoroughly examine the types of boosters that will be made available during the race. Dick's Sporting Goods only distributed Gu at the marathon, so I prepared myself during training. I took a few chocolate Gu's with me during the race in case they ran out of the chocolate flavor (which they did).

Experiment and have fun! :) Report
I used to take Endurox R4 post run, but now I just drink chocolate milk (much tastier) and gummy bears for carbs and nuun during the run...although I use gels during a race. I like eload orange and hammer gel apple cinnamon. Report
Thanks for the writeup! I just started a program with extra long runs on Monday, and I've got the hydration covered, but not the fuel. Honestly, the engineered sources make me wince; gels and blocs just don't sound very appetizing. I'm going to experiment with real food and see what happens. Report
I have tried several of the gels and the ones that I like the most are the rasberry Hammer gel. I just tried on my last run the watermelon sport beans (that was for you Nancy) and actually liked them ok. I liked the convience of being able to just take a few and not waste any of those left over at the end. I"ll use them on Saturday! I can really tell a difference in how I feel at the end of the run.

I tried to do fig newtons for a run - and they were good - but a bunch of crumbs by the time I tried to take them out of my pack. I'll stick with the convience of the engineered fuels I guess!

I am currently working on the timing of when I take them.... and I do think I'm getting close to having it down. We'll see on my 10 mile run Saturday!! Now I just have to make sure that I don't have to listen to "Cheeseburger in Paradise" again while trying to get a gel down - LOL!! Report