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Friday, August 20, 2010

Cocoa drink reduces DOMS. Really? Well, Maybe...

ResearchBlogging.org What if cocoa in a drink of protein and carbs could mitigate DOMS - delayed onset muscle soreness? This is what researchers in a newly published Aug 2010 study have explored. And thank goodness, since most of us have struggled with DOMS at one time or another - new routine and next day or next few days our muscles pay for it. We walk like cowboys coming off a long jaunt in the saddle. Could Cocoa with your recovery beverage of choice be the winner? Let's remember, there are very few approaches that have been shown to help reduce the signs of DOMS - those are detailed in this 2parter here - and as Mike T Nelson comments how we measure DOMS is pretty important when making claims about what is actually reduced in the DOMS experience. Just to recap
Let's review what's measured in assessing DOMS in the literature.
  • what's in the blood: usually there are markers in the blood like creatine kinase and LDH - these are markers of muscle damage - we may have the same CK levels and have very different responses to soreness
  • then there's the subjective measures of soreness themselves using rating scales.
  • then there's the more objective bits: Range of motion and force production.
Caveat Emptor
B2D buddie Mike T. Nelson of extremehumanperformance.com asks the question: is the experience of soreness directly correlated to a drop in performance? Mike in conversation makes the point that pain perception being a brain thing is going to be pretty individual. So how DOMS success is measured is something to bare in mind when looking at the studies following that claim to be effective against DOMS - are we talking DOMS pain reduction (always nice) or performance in a DOMS state?
Study Designing: So if one were to see if cocoa were effective how would we do it? Normally in an experimental condition, there's the thing being tested - in this case cocoa - and then there's a control - like water to see what happens without any intervention - and sometimes - in fact often - there's an alternative protocol, so you can see not just if the thing you're interested in has an effect but if it's the same or better than some usual standard - like a carb or protein+carb drink.


Now in a way, there have been a couple kinda similar studies: one that looked at chocolate milk vs something like cytomax (all carbs) and something like endurox (4:1 carb to protein) for recovery, not DOMS. In that study chocolate milk was shown to be as good as a carb beverage and better in a *certain test condition* than protein + carbs well all of us cheer that low-fat chocolate milk option. Except for the tons of folks for whom milk is not a happy thing, from lactose intolerance to immune responses with dairy. Intriguingly various dairy interests supported the research.

Just The Cocoa Facts, Sir. The question has been bound to come up well, what if we ditch the dairy and just look at the chocolate bit,  or in this case, the cocoa bit? Especially if this time the research is supported not by a dairy but a chocolate company. Hershies in this case. The researchers who did the reesarch also decided not to look at the big picture of recovery but to focus on DOMS reduction. Why? Because, they argue, we seem to see free-radical release go up conincident with the muscle damage of exercise, so perhaps, putting an anti-oxidant like cocoa into the system may help mitigate those effects and possibly reduce the DOMS experience. Interesting. And there's no small challenge they say in trying to measure anti-oxidant effect:

Although various experiments have been conducted to investigate the effect of antioxidant dietary supplementation on biomarkers of skeletal muscle damage and oxidative stress, the results are often equivocal and difficult to compare because of considerable variations in sampled populations and exercise protocols (18). Moreover, the practical application of antioxidant supplementation research studies has been considerably limited because of an overwhelming failure for measuring and reporting functional indices of exercise-induced muscle damage such as soreness (18). Therefore, the purpose of this pragmatic experiment was twofold: first to investigate the overall effectiveness of a welldefined custom manufactured cocoa-based protein and carbohydrate prototype drink on skeletal muscle cell damage and inflammatory biomarkers and perceived soreness associated with exhaustive exercise and secondly to assess if drink consumption before exercise offered additive effects. We hypothesized that the cocoa-based protein and carbohydrate prototype drink would decrease skeletal muscle cell and inflammatory biomarkers and perceived soreness compared to water, a standard fluid often consumed during exercise bouts.We also hypothesized that consuming the test drink before exercise would elicit further reductions in oxidative stress markers and perceived soreness.

Starting from Scratch. So thar ya go: the researchers will put together their own drink and compare it with water for effect on DOMS. They are going to use TWO of the four markers for DOMS described above: the biomarkers like CK and LEFS - Lower Extremity Functional Sacle. In LEFS, participants report on a scale of 0-4 the perceived difficulty of carrying out a physical task (actual survey here, pdf). So one biological test and one subjective scoring test. It is SUCH a drag that DOMS tests are not standardized! And asking someone to reflect *about* how they'd find getting out of a car if they haven't gotten out of a car, for instance, is yup pretty durn subjective. Interesting, but subjective when there are measures like ROM and force production also available, and even perceived soreness from pressure.

Findings about Cocoa in Particular? That aside, what did the authors find? Not too much. The drink had no effect on the biomarkers of damage. So they didn't mitigate its biological effects. The authors think however that their use of LEFS rather than the usual in DOMS studies VAS is a step up because LEFS asks about daily activities rather than just how a poke feels. And as to their results with LEFS checked at 24 and 48 hour intervals?
For those trials where the test drink was ingested after exercise we noted significantly less of a reported change from 24 to 48 hours by the participants. This indicated a decrease in perceived DOMS and therefore less difficulty in performing various physical tasks 48 hours postexercise.
Why does less change between 24-48 hours mean decreased DOMS?
DOMS gradually increases 24 hours postexercise and typically peaks 48 hours postexercise before beginning to decline (16).
Now i'm a bit annoyed that for this to be the BIG RESULT, we only get a couple summative values for the questionnaire rather than the raw data for lets face it, only 13 participants. Here it is
Consuming the test drink after exercise resulted in a mean change of 2.6 plus or minus 6 compared to 13.7 plus or minus 10 for the control.
In LEFS, the total score is out of 100, with a 90% confidence interval. What this suggests is that the scores changed by about 6 times as much in the non-drink case, which the authors suggest means that DOMS didn't get much worse in the drink case.

Here's personally where i'd actually like to see the raw data just to confirm that the direction of change for the non-drink group WAS that their scores went down (got worse) rather than up. We have to trust the authors' reporting. And i hate that.

The authors also spend considerable time speculating over why their form of cocoa rather than dutched may be a better use of cocoa to what's in chocolate milk


Concludium
This is why science is so cool: after an entire paper of data, experimental set up, discussion, yada yada yada, this is what we get
Based on the findings of our experiment we conclude that a recovery drink composed of a carbohydrate-to-protein ratio of 3.5:1 with the addition of flavonol-rich cocoa may (emaphasis mine -mc) decrease perceived muscle soreness after exercise.
There is nothing in the results to show that any one of the elements in this drink - the protein, the carbs or the chocolate - has any particular effect on mitigating DOMS. Indeed, one previous study that said cocoa is fine for ldl, but not for reducing inflamation, which would kinda suggest that cocoa mayn't help with DOMS.  The authors say that while there results show a similar lack of change in biomarkers, maybe it's the combination of protein/carb/cocoa that's having the effect. That is the subjective response.

Related Work. Interestingly, a previous study by Green and company that states rather categorically in its title that Carb or Carb/Pro drinks have no effect on DOMS is set aside by the present researchers. They suggest that really, Green's study didn't actually elicit anything with which to have a response to mitigate:
Therefore, it may be possible that the protocol of Green et al. did not impose adequate skeletal muscle cell damage to induce substantial perceived postexercise muscle soreness in participants. 
This helps the authors to say it's not cocoa alone; not clear that it's really not protein/carbs alone. 
 So all the more reason for the the authors to have studied a similar drink without the cocoa, rather than water, or along with water, they would have a stronger basis to assert that it's their anti-oxidant/flavonoid cocoa that's the Special Sauce for toning down DOMS. So why mightn't the authors have done something so obvious? I'd speculate something like the following.

The Gritty Realities of Reseasrch on a Shoe string - or Little Hershies Kiss
When one is designing a study, Saul Greenberg once suggested an heuristic to me about research i live by: think about the optimal outcomes of the study proposed. What will the best results be? Is that optimal outcome significant? If the authors of this paper had run that exercise what would they have said: the BEST we will be able to say if our results have an effect is that we will (a) see a difference in biomarkers and (b) see a difference in perceived soreness. And givent that, what will be be able to say about cocoa? Nothing. The best we will be able to say is that cocoa was in the mix and maybe it contributed to decreased DOMS, so best case: it's worth doing the next study to isolate this out. 

Why not do the full study the first time? It would take either longer or would take more participants. There are costs to that.  So, given that the authors didn't see any A but they did get some B which is sufficient to say "maybe" cocoa plays a role, i hope Hershies is sufficiently keyed up by this "maybe" to fund the next study that would compare the two formulations. Which will be the longer or bigger trial anyway. That could have been done from the start. But maybe Hershies said "what can you do with X dollars? if we like what you do maybe we'll give you X*y" - and so there we are.  Maybe. I speculate wildly.

Well what can i tell ya? What can i possibly say? 
All we do know from the data is that taking the drink before exercise rather than after exercise had no real effect on DOMS; taking the drink afterwards, the authors suggest based on their 24-48 hours DOMS increasing, shows it does.

So maybe maybe something in the composition and timing of the beverage that helped. What bit is a rather open question. One might say ah yes but there are other studies comparing say c.milk with carb/protein and the c.milk did better so it must be the C for Chocolate? Maybe. Maybe maybe and more maybe.

Might be a fun personal experiment: next time a new routine is in the offing, blend in those whole cacao beens and go nuts! you may even feel better for the next 24-48 hours. It's chocolate! how could it hurt?

Citations
McBrier NM, Vairo GL, Bagshaw D, Lekan JM, Bordi PL, and Kris-Etherton PM (2010). Cocoa-based protein and carbohydrate drink decreases perceived soreness after exhaustive aerobic exercise: a pragmatic preliminary analysis. Journal of strength and conditioning research / National Strength & Conditioning Association, 24 (8), 2203-10 PMID: 20634742

Karp JR, Johnston JD, Tecklenburg S, Mickleborough TD, Fly AD, & Stager JM (2006). Chocolate milk as a post-exercise recovery aid. International journal of sport nutrition and exercise metabolism, 16 (1), 78-91 PMID: 16676705

Mathur S, Devaraj S, Grundy SM, & Jialal I (2002). Cocoa products decrease low density lipoprotein oxidative susceptibility but do not affect biomarkers of inflammation in humans. The Journal of nutrition, 132 (12), 3663-7 PMID: 12468604

Wiswedel, I., Hirsch, D., Kropf, S., Gruening, M., Pfister, E., Schewe, T., & Sies, H. (2004). Flavanol-rich cocoa drink lowers plasma F2-isoprostane concentrations in humans Free Radical Biology and Medicine, 37 (3), 411-421 DOI: 10.1016/j.freeradbiomed.2004.05.013

Green MS, Corona BT, Doyle JA, & Ingalls CP (2008). Carbohydrate-protein drinks do not enhance recovery from exercise-induced muscle injury. International journal of sport nutrition and exercise metabolism, 18 (1), 1-18 PMID: 18272930


Related

5 comments:

  1. Some research has shown tart cherry juice to be efficacious, although I don't know how rigorous the research was.

    University of Vermont (2006, June 23). Cherry Juice May Prevent Muscle Damage Pain. ScienceDaily. Retrieved August 20, 2010, from http://www.sciencedaily.com­ /releases/2006/06/060623101220.htm

    BMJ Specialty Journals (2006, July 23). Cherry Juice Reduces Muscle Pain Induced By Exercise. ScienceDaily. Retrieved August 20, 2010, from http://www.sciencedaily.com­ /releases/2006/07/060721210534.htm

    Howatson et al. Influence of tart cherry juice on indices of recovery following marathon running. Scandinavian Journal of Medicine and Science in Sports, 2009; DOI: 10.1111/j.1600-0838.2009.01005.x

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  2. Interesting as I was actually apart of this cocoa study done at Penn State University which I believe was funded by a supplement company.

    Truthfully I do not believe I noticed much of a difference when given the drink or when given the water at least not enough for me to consider buying something like that drink.

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  3. Steven, great refs. will check 'em up for sure.

    Tanner, which cocoa study? this aug 2010 one? cool. According to the paper, the funding is from Hershies - perhaps not exclusively but that's whom the authors thank.

    Thanks for the feedback. So would you say the DOMS you experienced after the water trial and the cocoa trial were pretty similar then?

    that's certainly within the range of overlap in the two conditions.

    (2.6 +/- 6 and 13.whatever +/- 10)

    Thanks a bunch both of you.

    mc

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  4. Interestingly, cocoa powder was actually the first bodybuilding supplement. Eugene Sandow had a whole cocoa factory and everything. The chocolate companies crushed him like a little bug.

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