Should You Use Carbohydrate-Protein Sports Drinks?

Again, I’ve got to apologize for the big gap between posts here recently. The recent sell of our home in Boulder and move to new temporary quarters combined with two book projects and travel has left me a bit tight for time. But, as promised a couple of weeks ago, here is a post on carbohydrate-protein drinks.

It’s been a while since I wrote about this topic, a relatively new one with roots back in the 1990s. That may seem like a long time ago, but in the big scheme it’s not that long since we used carbohydrate as the only fuel source in our sports drinks. (The electrolytes we typically add to sports drinks are another post altogether, which I’ve written about before. )

Over the past 15 to 20 years there has been a lot of interest in protein intake during exercise. The attention this topic gets in the endurance sports media seems to have plateaued in the last couple of years. It seems we don’t hear as much about this subject any more. Perhaps that means it’s come to be commonly accepted and therefore isn’t in need of as much promotion any longer. It seems that many of the athletes I talk with use carb-protein drinks now, especially in shorter events taking less than 3 hours. For the longer events there seems to be fewer users, or at least that’s my impression. Many of the Ironman triathletes I’ve spoken with tell me they have experienced stomach shutdown when using carb-protein drinks. (Adding protein to your drink slows the processing of the gut’s contents.) I don’t know if they are typical of all Ironman athletes or not, however.

I noticed in the last couple of years that there were several new studies on the topic. I’ve been collecting them and finally set down to start reading. This turned out to be a much bigger project than I expected.

The original studies I had read on such products several years ago all seemed to have the same issues. The typical study had athletes exercise to exhaustion (failure) on 3 or more occasions. On one they drank a carb-only solution. On another they drank a carb-protein drink. And for the third they usually used an artificially sweetened placebo. These studies typically found that the carb-protein drink produced a significantly longer time to exhaustion than the carb-only or the placebo.

There are there issues I’ve seen with these studies. The first is that athletes don’t exercise to failure at a fixed and unwavering effort in a race. I’d prefer to see a more racelike standard used, such as a time trial, actual race or something similar.

The second issue is a bigger one. These studies nearly always have had more total calories in the carb-protein drink than in the carb-only drink. That, it seems to me, is a significant flaw which tilts the field in favor of the carb-protein drink.

And in some of the studies there is even a third important issue. These studies use a carb-protein drink in which the carb is a mix of several sources, such as fructose, maltodextrin and sucrose. Mixing multiple carbs together in a sports drink has been shown to improve the carb uptake significantly (like 44% more) when compared with the same amount of calories from a single-source carb (see the Sawka [11] and Jentjens [5] studies below).

These seem to me to be critical issues. So I’ve found it hard to accept the position that there is a definite benefit to using carb-protein drinks, especially if there is the possibility of gut problems as some athletes have suggested. It may be that they do work better than carb-only, but the studies aren’t convincing given their issues.

So with this in mind I set out to read the more recent research to see what was being discovered. Basically, I didn’t see much of a change. Below I’ve listed the studies I could find that go back to 2003 and include 5 from 2010 and 2011. (By clicking on these you can go directly to the abstracts on PubMed should you want to read a few more details and draw your own conclusions.)

Rather than go through all of these, which would be a rather tedious blog post, I’ll instead offer the details from only one – a review of the literature from Stearns and associates at the University of Connecticut which was published last year [12].

The UConn paper examined 11 studies which met their standards for inclusion in the project. Three of these selected studies had time trials as the measured standard. Eight of them used time to exhaustion to gauge the results of the drinks used. Only 3 of the studies cited had equal calories for the carb-only and carb-protein drinks. The others had more calories in the carb-protein solutions. (Stearns et al did not address the mixed-carb issue.)

So what did the UConn review find? The 3 time trial studies showed no significant difference in performance between the two drinks. Of the 8 studies that used time to exhaustion, those with equal calories had no performance difference. It was only in the time to exhaustion studies that also provided more calories in the carb-protein drinks where there was a significant difference in performance.

The benefits found for carb-protein drinks in these few studies, according to the UConn researchers, “may be because of a generic effect of adding calories (fuel) as opposed to a unique benefit of protein.”

So should you use a carb-protein drink or a carb-only drink in your longer workouts and races? (There is no benefit from either for short sessions – those lasting no longer than an hour or so.) If you haven’t experienced any stomach problems from using a carb-protein drink then I see no reason to make a change. There’s no other apparent downside. But if you have, or you have no experience with such products, then I’d suggest sticking with carb-only as it has a long and successful history.

I might add that there is one missing piece here: Some of the studies examined the benefits of carb-protein during and after exercise for the rate of recovery. This could be an important matter that stands apart from performance. I hope to address that in a future post here.

References

1. Betts JA, Stevenson E, Williams C, Sheppard C, Grey E, Griffin J. 2005. Recovery of endurance running capacity: effect of carbohydrate-protein mixtures. Int J Sport Nutr Exerc Metab 15(6):590-609.

2. Breen L, Tipton KD, Jeukendrup AE. 2010. No effect of carbohydrate-protein on cycling performance and indices of recovery. Med Sci Sports Exerc 42(6):1140-48.

3. Ferguson-Stegall L, McCleave EL, Ding Z, Kammer LM, Wang B, Doerner PG, Liu Y, Ivy JL. 2010. The effect of a low carbohydrate beverage with added protein on cycling endurance performance in trained athletes. J Strength Cond Res24(10):2577-86.

4. Ivy JL, Res PT, Sprague RC, Widzer MO. 2003. Effect of a carbohydrate-protein supplement on endurance performance during exercise of varying intensity. Int J Sport Nutr exerc Metab 13(3):382-95.

5. Jentjens RL, Achten J, Jeukendrup AE. 2004. High oxidation rates from combined carbohydrates ingested during exercise. Med Sci Sports Exerc. 36(9):1551-8.

6. Martínez-Lagunas V, Ding Z, Bernard JR, Wang B, Ivy JL. 2010 Added protein maintains efficacy of a low-carbohydrate sports drink. J Strength Cond Res 24(1):48-59.

7. McCleave EL, Ferguson-Stegall L, Ding Z, Doerner PG 3^rd, Wang B, Kammer LM, Ivy JL. 2011. A low carbohydrate-protein supplement improves endurance performance in female athletes. J Strength Cond Res 25(4):879-88.

8. Romano-Ely BC, Todd MK, Saunders MJ, Laurent TS. 2006. Effect of an isocaloric carbohydrate-protein-antioxidant drink on cycling performance. Med Sci Sports Exerc 38(9):1608-16.

9. Saunders MJ, Kane MD, Todd MK. 2004. Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage. Med Sci Sports Exerc 36(7):1233-38.

10. Saunders MJ, Kane MD, Todd MK. 2005. Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage. Med Sci Sports Exerc 37(1):166.

11. Sawka MN, Burke LM, Eichner ER, Maughan RJ, Montain SJ, Stachenfeld NS. 2007. Exercise and fluid replacement. Med Sci Sports Exerc 39(2):377-90.

12. Stearns RL, Emmanuel H, Volek JS, Casa DJ. 2010. Effects of ingesting protein in combination with carbohydrate during exercise on endurance performance: A systematic review with meta-analysis. J Strength Cond Res 24(8):2191-202. 

13. Valentine RJ, Saunders MJ, Todd MK, St Laurent TG. 2008. Influence of carbohydrate-protein beverage on cycling endurance and indices of muscle disruption. Int J Sport Nutr Exerc Metab 18(4):363-78.

Comments

[John Cristiano]

I have gone through 2 occasions of stomach shutdown when using a carb-protein drink during an Ironman. I had very good results with the product during training (with bricks up to 6.5 hours in length), but at about the 8.5 hour mark the shutdown issues began.
Are there any recommendations about the amount of calories/carbs per hour as I start to look for a new nutrition strategy going forward? Also, do you see any possible benefit to using a carb-protein product for the first portion of a race prior to switching to something simpler to digest (I'm thinking around mile 60 on the bike where special needs typically is staged)?

Thanks,

John

[Colm]

I understand the point that the calories were higher in certain trials, but were the quantities of fluid used the same? It could make a difference over long distance if you can more bang for your fluid oz?

[Joe Friel]

Colm--If I recall right, every study had the subjects use the same amount of fluid for each trial. But feel free to check for yourself with the abstracts links provided under References.

[Joe Friel]

John Cristiano - The standard answer is 240 cal/hour. But that will vary with body size, exercise intensity, and personal experience.

[Rebecca Frederick]

One other thing that is missing from most of these studies is any potential gender differences - is there good recent evidence that it works the same or differently in women?

[Jay Austin]

Joe,
Thanks for taking the time to write so much. Everyone is fantastically busy, and given your schedule I can't imagine how you find the time to squeeze out even one blog post per month...

Anyway, my question is a follow up to the "240 calories per hour" standard.

I recently listened to a very interesting podcast where Sunny Blende was interviewed by www.Ultrarunnerpodcast.com

She noted that fructose and sugars (other than sucrose) get processed by the liver before they become available for the muscles to do work. She called this a separate pathway and allowed for a slight increase in calorie per hour standard.

Reading your post here made me wonder if there isn't another route for protein too. And if so, is it different enough that you can slightly increase your caloric intake per hour by adding protein to your 240/hr?
Thanks again.
J

[Joe Friel]

Jay Austin--I know of no 'separate pathway' for protein. Sugar is closely monitored and processed by the body as it is viewed almost as a toxic substance. So the body does unique things with it (e.g., converted to glycogen, glucose or fat very quickly after processing) that it doesn't do with fat or protein. Again, the standard 240 cal does not take into account body size etc.

[Joe Friel]

Rebecca--Yes, if you look down the list of refs you'll find one that focused on women. A couple of the others also had male and female subjects. These found no differences if my memory serves me right. But can check for yourself also.

[DS]

Great post. I'm 4:1 carb:protein user, and it works for me -- it keeps me from getting that queasy-depleted feeling after 5-6 hours of just taking in sugar. I'd never considered that the effect might be from the added calories. Very interesting.

It would seem that the presence of the protein would slow the rate of absorption of the sugars, i.e., lower the glycemic index of the drink. This would help some people avoid problems with blood sugar spiking in response to a pure-carb intake, then crashing as insulin surges in response to the spike in blood sugar.

[Henry]

Joe - What about the consumption of BCAAs vs other forms of protein (whey or casein)? Many drinks are starting to add protein in the form of these BCAAs and they claim to be absorbed easily and not cause and stomach shutdowns. Also, I know this article is about Carbs and Protein but what about Fats from Multi Chain Triglycerides (MCTs)? My understanding is that these also have some benefits for Endurance athletes and I personally have not had any stomach issues when consuming them.

[Tad Fullerton]

Great post.

I've been reading two books by John Ivy and Robert Portman, Nutrient Timing and The Performance Zone, and these advocate protein and carbo, seem to be well referenced and may be of interest to you. Nothing in these books go out anything like 8 hours though. It seems like protein in the post exercise drink is benificial.

Tad

[Chris Livingstone]

Joe--Can you summarize recommendations for a sports drink for use during exercise? Is there a commercial product you favour, or a recipe for a homemade one?

Thanks,

Chris

[David]

Joe,

I have been interested in this post ever since you mentioned it. Thanks for sharing your knowledge, opinions and experience with us.

You mentioned "sports media endurance" in the earlier part of your post. Then in the latter part of your post you pose the rhetorical question of whether or not to use a carb-protein drink mix and also mention that there is no benefit/downside for exercise sessions less than an hour. This raises a big question for me, how long were the exercise sessions of the studies? How long was the time trial? In my honest little opinion I wouldn't consider 60 minutes and maybe not even 3 hours an "endurance" session. When I think of endurance, I think of a marathon, or a cycling century that takes 5 to 6 hours to complete.

I just completed my first LOTOJA (which I owe this success in great part to incorporating as much as your Racing Bible knowledge into my training as I could). In the past year I have been learning to train and complete endurance events with nothing more than water, sports drink mix, sports gels and an electrolyte supplement. The sports drink uses a mix of complex carbohydrates, maltodextrin and just a bit of sugar (about 1/6 to 1/8 of total carbs), soy protein and fat.

It took me just over 11 1/2 hours to complete the 206 mile ride while consuming no solid food; just the above described energy sources. I personally swear by this program. At the end of the 206 miles I felt like I could have kept riding until the sun went down, I felt great. The legs were still firing and at that time I had no stomach distress. Introducing solid foods afterwords was a bit interesting but not a big problem. I would argue that there is a benefit to carb-protein-fat drinks; I guess I am not sure how to compare them to Carb-protein drinks.

But my main point is, I would not use a carb-protein drink on any exercise session lasting less than 3 hours; sub-60 minute session would be unheard of for me. It seems to me like the protein would not be necessary until MAYBE after two hours, but most likely 3 hours or more, so why are there studies for shorter sessions, but not long endurance sessions of several hours, like 6, 8, or 10? That is what I would like to see some data on.

Thanks

Dave

[Joe Friel]

David--Most of the studies used time to exhaustion at a set percentage of, for example, VO2max following a long warm up of usually several hours. If interested follow the links for each study for more details.

[Joe Friel]

Chris L--It's pretty much an individual call based on taste, cost, availability, etc. For my 3h and longer rides I use Coco-Cola.

[Joe Friel]

Henry--Yes, there are studies on these nutrients in sports drinks also. I wrote about them in my Training Bibles.

[Jonny Creatine]

I've never seen advice to take protein during exercise, only before and after. I can't see how it could fuel athletic performance effectively so quickly?

[bmi converter]

Hi Joe,
Can you let me know what brand or what is the name of the Carbohydrate-Protein drink that you have tried? Maybe you can recommend one... don't worry, I will not blame you if I got burn out..

[Joe Friel]

bmi--I don't use CHO-PRO drinks at all.

[Iron Mineral]

Hi Joe,
What are health benefit of protein supplement?

[Joe Friel]

Iron--Supplements are best avoided. Eat real food. If for some weird reason you can't then use a supplement--sparingly.

[Paul Lundgren]

Joe,
Based on my personal observations the benefit of a carb/protein drink is not worth the risk of stomach issues in events under x-hours. My concern is with events over the norm in time. I'm struggling with 12 to 50 hour events and finding the optimum solution that works with both digestion and physical requirements. The question I have is at what point does protein become more of a concern and do you recommend a ratio of carb/protein in stages of time?
Thank you,
Paul

[Joe Friel]

Paul--Personally, I don't think protein is every necessary during a ride. That said, if you're going to use it very, very long rides would be the time--as in RAAM and most long brevets.