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marylin monroe
Showing posts with label time to exhaustion. Show all posts
Showing posts with label time to exhaustion. Show all posts

3.2g of Beta Alanine Reduce Rate of Perceived Exertion, Increase Time to Exhaustion and Ventilatory Threshold. Vegetarians, Older People and Diabetics May Benefit Most.

Image 1: If you are into running, ladies, beta alanine is for you ;-)
Those of you who make sure that they are getting their highly educative daily dose of the SuppVersity *rofl* will be aware that today's blogpost is, once again, dealing with beta alanine. Contrary to yesterday's post, which dealt with its pharmacokinetics, we are today going to have another look at what kind of real world performance outcomes the average (female!) physical culturist can expect from taking at least 3.2g of the beta amino acid per day - a dosage that has been shown in previous studies to increase intra-muscular carnosine levels by 27–39% in fast- and slow-twitch muscle fibers, respectively (Baguet. 2009). And though I do not want to spoil things, I can already tell you that the results make it quite clear why beta alanine is not the next creatine.

Somehow ergogenic, yet not really antioxidant

For the study that was conducted at the Applied Physiology Laboratory at the University of North Carolina, study that was conducted by A.E. Smith recruited 24 "recreationally active" women, of which the authors state that they "engag[ed] in 3–7 days per week of aerobic, resistance or recreational activities, but were not highly trained competitive athletes". With a mean age of 21.8 years, a height of 165cm and a body weight of 61.5kg the subjects are thusly representative of the average young woman who goes to the gym to either get or keep in shape. I am specifically emphasizing this, because - at least in the early days - beta alanine was heavily marketed as "the creatine for women" who fear the water retention people still claim was an inevitable side effect of creatine supplementation.
Image 2: If you retain water, this is not due to creatine monohydrate. Either you are taking to much (creatine loading is a thing of the past) or you have bought a product with shitloads of carbs in it - in that case, chances are its not only water you are gaining ;-)
Does creatine supplementation inevitably lead to water retention and weight gain? Just because this myth is still perpetuated, especially among female figure competitors, I thought it may be worth addressing this again: Pure creatine monohydrate without the sugar and the other bullshit you will find in many creatine supplements does not necessarily lead to increases in either total body or water weight. A study by Rawson et al. showed only recently that the consumption of 0.03g/kg creatine for six weeks did not result in statistically significant changes in body weight or water in men or women, despite significantly increased plasma creatine concentration and enhanced resistance to fatigue during repeated bouts of high-intensity contractions (Rawson. 2011).
The women were advised to simply stick to their usual routine and to refrain from taking any supplements and medications except from their 2x800mg beta alanine tablets. The latter were to be taken 3x a day... so according to Cocker, they should have consumed 2x0.8g x3/day = 4.8g/day and not, as the scientists state "3.2 g daily". Now, according to Smith et al. this was the "required dosage" all participants met. I can however not say, whether this means that the third dose was optional... and this is not the only oddity in this study, where it is well worth to look beyond the assessments and conclusions of the authors.

At the beginning and the end of the 28-day supplementation period, the women had to perform a graded oxygen consumption test (VO2max) to evaluate VO2max, time to exhaustion, ventilatory threshold and establish peak velocity (PV), as well as a "non-damaging treadmill run (oxidative stress run) for 40 min at 70% PV [peak velocity]". Before, immediately after and in the 2-6h post running window total antioxidant capacity (TAC), superoxide dismutase (SOD), 8-isoprostane (8ISO) and reduced glutathione (GSH) were measured. In addition to that, heart rate and ratings of perceived exertion were recorded during the 40 min run. The two main metrics of the study were thusly the potential anti-oxidant effects (TAC, SOD, 8ISO, GSH) and the anticipated immediate ergogenic effects (VO2Max, time to exhaustion, heart rate and perceived exertion) of beta alanine supplementation.
Figure 1: Effect of 28 days of beta alanine supplementation on maximal oxygen consumption (VO2max), time to exhaustion during a graded exercise test (VO2TTE) and ventilatory threshold (VT) and qualitative practical significance (data and caption adapted from Smith. 2011)
If you now have a look at the my graphical rehash of the scientists own evaluation of the effect beta alanine supplementation had on VO2Max, the time to exhaustion (VO2TTE) and the ventilatory threshold (VT), you will have to concede that mean improvements of 0.28%, 6.6% and 3.7%, respectively, as well as the large discrepancies among the subjects (from beneficial over negligible to harmful) do not actually speak for beta alanine.
Figure 2: Effect of beta alanine supplementation on oxidative stress markers measured as total
antioxidant capacity (TAC) and glutathione (GSH) and the qualitative practical significance
for women (data and caption adapted from Smith. 2011)
Things get even more confusing when we take a look at the antioxidant effects of beta alanine. Not only were the levels of superoxide dismutase (SOD) and 8-isoprostane (8ISO) not different between groups, and the effect of beta alanine on the total antioxidant capacity (TOC) of the subjects negligible, the scientists' summary of the effects does even suggest that, after an initial amelioration of the negative effect of treadmill running on GSH, there was some sort of a "likely harmful" rebound 6h after the 40 min exercise bout. Before you do now flush your beta alanine stores down the toilette, I suggest you first take a look at the actual (absolute) effects beta alanine supplementation had on the exercise induced changes in GSH levels:
Figure 3: Absolute GSH levels (in µM) immediately before (pre), post, 2h and 4h after treadmill running in the placebo and beta alanine supplemented women before (pre) and after (post) the 28-day supplementation period (compiled based on data from Smith. 2011)
As you can see in figure 3, there was an (unexplained) increase in GSH in the course of the 28-day supplementation period in both groups. With 2%, the latter was statistically non-significantly greater in the beta alanine group, and the "likely harmful" effect of beta alanine supplementation 6h after the end of the treadmill-run is simply the result of a smaller increase in GSH, when you compare the pre- to post-supplementation levels at the 6h mark - and I guess, you would agree that a +27% increase in GSH is not exactly something that deserves to be called "likely harmful", wouldn't you?

All-clear: Beta alanine is not ergolytic ;-)

Now that we have gotten that straight, let's get to the last (and most) significant benefit the women in the beta alanine group had from taking the supplement: a statistically significant reduction in the rate of perceived exertion during treadmill running (cf. figure 4).
Figure 4: Rates of perceived exertion during 40 min treadmill running before (pre) and after (post) 28 days of supplementation with beta alanine or placebo; small graph: relative difference post supplementation in women receiving BA vs. placebo (data calculated based on Smith. 2011)
It goes without saying that being 18% less fatigued is something that could well be worth spending the roughly 7$ for a 28-day supply on (calculation based on a dose of 3.2g per day taken over 28 days and assuming you buy your beta alanine in bulk at one of the major suppliers). This, by the way, could be particularly true if you belong to one of the following groups, who have been found to have low intra-muscular carnosine levels, to begin with:
    Image 3: Older people are only one of the three groups who are "at risk" of low carnosine levels and are thusly most likely to benefit from beta alanine supplementation.
  1. vegetarians - a 2011 study by Evaraert et al. found that "Vegetarians have a lower carnosine content of 26% in gastrocnemius compared to omnivores" (Everaert. 2011); and according to another recent study, the soleus carnosine content of vegetarians was "non-significantly" reduced by -9% after 5 weeks of sprint training, while the same protocol elicited increases of +11% in omnivores (Baguet. 2011)
  2. older people - Evaraert et al. found a linear decline (ca. -10% in 20 years) in carnosine levels with age (correlation r=-0.26; Everaert. 2011); and Stout et al. report a highly significant +29% increase in physical working capacity at the fatigue threshold in twenty-six men (n = 9) and women (n = 17) (age ± SD = 72.8 ± 11.1 yrs) who  had been supplementing with 800 mg three times per day for 90 days (Stout. 2008)
  3. type-2 diabetics - according to Gualano et al. type-2 diabetics have "significantly lower carnosine content (−45%) in gastrocnemius muscle", a relative deficiency of which the scientists argue that it "may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle." (Gualano. 2011)
After all, it does yet not really matter whether you are a type-2 diabetic, a vegetarian or simply getting older, compared to many (if not most) of the other overpriced ergogenics that are advertised all over the web, beta alanine is certainly not only one of the cheapest, but also one of the most promising candidates for the 3rd place on your list of staples, where (whey) protein and creatine should nevertheless still occupy position 1 and 2, respectively. And the fact that it did not prove to be a potent antioxidant in this study need not really be a disadvantage, after all, we still do not know whether the exercise-induced oxidative "damage" is not what actually triggers the highly desirable adaptive responses (cf. previous posts on "hormesis"), we are all looking for, when we are hitting the gym.

    XS® Energy Drink Practically Useless for Athletes: Not Even eXtra Small Improvements in Exercise Performance

    XS Energy Drink. 0 sugar, only 83mg caffeine.
    Probably tasty, but not ergogenic.
    If you believe the marketing campaigns of supplement manufacturers (and, of lately energy drink producers), performance - just as about everything in our society - is for sale (in this case at the local GNC). You, as a regular visitor to the SuppVersity are yet aware that supplements, if they do work at all, usually provide a rather minute performance increase that - and here is where the magic happens - may nevertheless decide a head-to-head finish in your favor. It is thus very expedient that XSBlast refers to this X-tra S-mall advantage of their product line in their company name already... wait! You think they imply "XS" as in eXceSs? Well, I guess in the end it does not really matter, because their XS® Energy Drink, a mixture of 83mg caffeine, 1.5 g taurine, 6.0 mg Vitamin B6, 294 µg Vitamin B12, 10 mg Vitamin B5, 20 mg Vitamin B3, 24mg Sodium, 25mg Potassium, as well as undisclosed amounts of L-Glutamine, Citric Acid, an Adaptogen Blend (Eleutherococcus Senticosus, Panax Ginseng, Panax Quinquefolium, Schisandra, Astragalus, and Reishi), Natural Flavors and the artficial sweetener Acesulfame, does not seem to come up to any of these implications.

    Supported by an independent research grant, K.M. Sheehan and L.K. Hartzler from the Department of Biological Sciences at Wright State University, Dayton, OH, USA, investigated in a double-blind cross-over study protocol (Sheehan. 2011) the effect of a single serving of XS® Energy Drink on subsequent exercise performance of 12 athletes (sex: 9m, 3f; age: 18-24 y) in a modified Ellestad Treadmill protocol and found:
    Vo2max (p=0.99), time to muscle fatigue (p=0.48), maximum heart rate (p=0.66), [minute ventilation  max] VEmax (p=0.10), time at which [respiratory exchange ratio] RER is greater than 1 (p=0.50), or recovery time to one half Vo2max (p=0.67) were not significantly different with ingestion of XS® Energy Drink over placebo. 
    Accordingly, the conclusion of the scientists, that "[e]ven with all sources of error taken into account it is still not likely that acute consumption of XS® Energy Drink, in the amount used in this experiment, has an advantageous performance effect" is valid for the whole spectrum of effect sizes from XS as in eXtra Small to XS as in eXceSsive ;-)

    In view of some of the proclaimed ergogenics in the drink and the load of B-Vitamins having a possible effect on cognitive performance, as well, I would really like to see a study into these effects of this drink. Maybe, this is where the XS® Energy Drink produces eXceSsive results, after all.

    Putting Carbs to Good Use: Meta-Review Reports Ergogenic Effect of Carbohydrates in Endurance Athletes

    One of the leitmotifs, many of my posts here at the SuppVersity share, is the idea that (almost) everything works for someone. From the feedback I am receiving, from the crowd this blog is attracting, I gather that my general advice against high carbohydrate intake is (as human as that may be) often misinterpreted as "carbs are evil, beware of all carbs"! For the average pizza eating fast-food junkie, this certainly is an adequate message, because even if he believes that carbs are the root of all disease, without a MAJOR change in his dietary habits (I am not talking of ordering the normal, instead of the super size menu at McDonalds, here) he will probably still get way more carbs out of his diet than it would fit his sedentary lifestyle.
    If, however you are an athlete or avid gym-goer you may probably already start to notice that following what you took to be a one-solution-fits-it-all recommendation lead to performance decreases, laziness, brainfog, lack of sexual desire, bad sleep and many of the other symptoms you would find, when you googled one of the ambiguous terms "adrenal fatigue" or "general fatigue syndrome"... Carbs are more than just insulin triggers, and fatteners. Glucose is the gasoline in your fuel tank and - most importantly - its the substrate your nervous system thrives on. And while it might not be necessary to eat them, very active (and lean) individuals may derive similar benefits from a moderate carb consumption as the athletes from the 50 studies included in a meta-review by Themesi et al. (Themesi. 2011).

    The scientists' results suggest that intake of a <8% carbohydrate beverage (~50-80g) [TT] in the course of an endurance event (≥1 h) significantly "enhances endurance exercise performance in adults" as measured by submaximal exercise performance and time to exhaustion [TTE]:
    The ES [effect size] for submaximal exercise followed by TT was significant (ES = 0.53; 95% CI = 0.37–0.69; P < 0.001) as was the ES for TT (ES = 0.30; 95% CI = 0.07–0.53; P = 0.011). The weighted mean improvement in exercise performance favored CHO ingestion (7.5 and 2.0%, respectively). TTE (ES = 0.47; 95% CI = 0.32–0.62; P < 0.001) and submaximal exercise followed by TTE (ES = 0.44; 95% CI = 0.08–0.80; P = 0.017) also showed significant effects, with weighted mean improvements of 15.1 and 54.2%, respectively, with CHO ingestion. Similar trends were evident for subanalyses of studies using only male or trained participants, for exercise of 1–3 h duration, and where CHO and PLA beverages were matched for electrolyte content.
    Against this background, can the relevant question really be: "To carb or not to carb?" Probably not. You better follow Vince Andrich's recent advice and ask yourself "Are you working your sugar-bags (muscles) hard enough to earn your fair share of carb intake?" in order to make sure that you use just as much carbs as it takes to optimize performance without compromising health and body composition.

    Exercise Threesome: 40g of Galactose = 17% More Stamina Than W/ Same Amount of Glucose ☆ Faster Sprints W/ Psychological Tricks ☆ 10% Lower Insulin W/ Exercise

    A neat threesome, anyone?
    A threesome is always quite entertaining, especially, when it's one that can help you (a) increase your stamina, (b) boost your sprint performance, and (c) decrease your fasting insulin levels by 10%. Ok, I have to admit it will probably not suffice if you only read the following paragraph, but buying 40g of galactose, playing a couple of psycho-games on yourself and the adherence to the regular exercise program you are already performing anyway (right!?) is something you will probably manage to do, as well.
    • 40g galactose before a workout will increase your stamina (O'Hara. 2014) -- Basically that is already the main finding of a recent study by John P. O'Hara et al... well, aside from the fact that the same dose of glucose didn't produce similar benefits - but let's tackle one thing after the other...

      The researchers evaluated the effects of the pre-exercise (30 minutes) ingestion of galactose (Gal) or glucose (Glu) on endurance capacity, as well as glycaemic and insulinaemic responses.

      To this ends 10 trained male cyclists completed three randomised high-intensity cycling endurance tests. Thirty minutes prior to each trial cyclists ingested 1 litre of either
      • 40g of glucose,
      • 40g of galactose, or
      • 40g of a placebo
      in a double blind manner. The protocol comprised: 20 minutes of progressive incremental exercise (70% to 85% maximal power output (Wmax)); 10x90 second bouts at 90% Wmax, separated by 180 seconds at 55% Wmax; 90% Wmax until exhaustion.

      Blood samples were drawn throughout the protocol. As the headline already told you the times to exhaustion were longer with glactose (68.7+/-10.2 minutes, P=0.005), interestingly that was true for both the placebo (63.9+/-16.2 minutes) and the glucose (58.5+/-24.9 minutes) trial.

      In view of the anti-lipolytic effects of high insulin, it's probably also worth mentioning that the ingestion of 40g of performance-increasing galactose supplement did (at least from a statistical perspective) not increase the participants insulin levels, at all.
    • SuppVersity HIGHLY Suggested Read: " Brocebo? Add 10kg to Your Bench in Days with Sugar-Based "Anabolic Steroids". Old Study Shows, Many "Natural Anabolics" Could Work Solely via Placebo Effects" | read more
      Psyching yourself up will boost your sprint performance (Sarra. 2014) -- A soon-to-be-published study in the Journal of Strength and Conditioning Research that investigated the effect of "psyching-up" (PU) strategies, in this case preparatory arousal and imagery strategies, would improve the performance of 16 male sprinters (age 20.6 +/- 1.3 years, body mass 77.5 +/- 7.1 kg, height 180.8 +/- 5.6 cm).

      If we sprint forward to the results, we'll see that the imagery and preparatory arousal strategies did in fact contribute to performance increases in the short-distance sprints (from 0 to 10-m). The imagery strategy also increased the performance in the 30-m sprints.

      And you know what? These "psyching-up" strategies work even if you don't buy a useless supplement take it before your workout and ignite the "placebo afterburner"
    • Work out to decrease your fasting insulin levels by 10% (Conn. 2014) -- In spite of the fact that we all believe we knew that regular exercise will have beneficial effects on  insulin sensitivity, there is very little comprehensive data on the average effect size.

      A recent meta-analysis from the University of Missouri provides just that: A "Systematic Review and Meta-Analysis of Outcomes Among Healthy Adults", which reveals what the subheading to this item in today's exercise news-quickie already told you: The average participant in one of the 78 papers that were included in the analysis showed statistically lower fasting insulin levels (6.9mU/L) than the control subjects (7.9 mU/L).
    Bottom line: If you are already working out regularly, you may want to try to psyche you up, while you're guzzling a galactose drink before your next workout and let me know what happened, after you tore down the gym... if you are not, I mean, not working out, on the other hand, the decrease in insulin you can achieve with a minimal amount of physical activity should be reason enough to get your ass off the couch... and no, I am not talking about walking to the fridge to get another bottle of coke and some ice-cream to satisfy your sweet tongue ;-)
    Reference:
    • Conn V. S. et al. "Insulin Sensitivity Following Exercise Interventions: Systematic Review and Meta-Analysis of Outcomes Among Healthy Adults." J Prim Care Community Health. (2014) Jan 27. [Epub ahead of print]
    • Hammoudi-Nassib, S. et al. "Effects of psyching-up on sprint performance". Journal of Strength & Conditioning Research. January 28, 2014 [accepted manuscript].
    • O'Hara, J.P. et al. "The Effect of Pre-exercise Galactose and Glucose Ingestion on High-Intensity Endurance Cycling". Journal of Strength & Conditioning Research. January 28, 2014 [accepted manuscript].