Enduro Bites fueled @battlethebear
Cycling Performance while on a Low-Protein Vegetarian Diet
A study published yesterday looked at the effects of a low-protein, vegetarian diet on blood pH and cycling performance. Led by Dr. Hietavala, researchers from University of Jyväskylä in Finland hypothesized the following.
“a diet low in protein and rich in alkali-producing vegetables and fruits may have the potential to alter the blood acid-base status and, thus, enable higher aerobic capacity and influence fuel selection during exercise.”
On the first count, researchers didn’t see any change to blood pH after having subjects follow a low-protein vegetarian diet (LPVD). However, they only had the subjects follow this diet for four days, so perhaps this wasn’t long enough to see an effect.
Even though no pH changes were seen, researchers observed something unexpected.
“…energy expenditure was greater and cycling economy poorer after LPVD.”
In other words, after following the vegetarian diet the subjects had to expend more energy to perform a set amount of work during cycle ergometer testing. Dr. Hietavala’s team concluded the following.
“According to these results, a low-protein vegetarian diet cannot be recommended as a means to improve submaximal or maximal aerobic performance via acid–base balance as opposed to what was hypothesized.”
So, the question now is, what caused this performance decrease? Is it possible that the vegetarian diet given to the subjects was too extreme? Was it too low in protein and/or calories? Was the limited grain or dairy intake a factor? Did subjects not have enough time to adapt to it?
As often happens, this study yielded more questions than answers. I’m excited to see where this leads.
Image from courtesy avlxyz (http://www.flickr.com/photos/avlxyz/2695730538/sizes/l/in/photostream/).
Enduro Bites visits Rapha Cycling Club San Francisco.
Is it in Your Genes?
by Brian Maslach
Would you want to take a test to learn how well you may respond to exercise? If so, would the results make a difference in how you exercise?
A British company, XRGenomics, now offers a DNA test to the public that they claim will show whether you are likely to be a low or high fitness responder.
One major flaw is that the test seems to look exclusively at genetic markers relating to one’s VO2 max. The problem with this is that some world-class endurance athletes, such as the father of American endurance running, Frank Shorter, have overcome relatively low VO2 max levels to become amazing athletes.
On a more widespread basis, I’m concerned that many people would fall back on their low-responder rating as an excuse to simply not exercise. The last thing we need in the midst of this obesity epidemic is to tell people that their genetics are stacked against them when it comes to improving fitness. The population as a whole is already at an all-time low in their physical activity.
Humans are emotional beings. We largely gravitate to things we like, and this is definitely the case when it comes to the type of exercise we do. The key to getting inactive individuals to become physically active is finding activities they enjoy. Telling someone that they are likely to never be very good at cycling, running, or any other endurance activity can keep them from becoming physically active in the first place. This flies in the face of getting people to simply move more, which most health experts agree is one of the most important things we can do to improve the health of our nation.
The recent story of Ernest Gagnon, a man who weighed nearly 600 pounds when he began cycling rather than undergo surgery to lose weight, comes to mind. When faced with depression and serious health implications as a result of his weight, he reportedly had an epiphany and decided he wanted to make his childhood desire to race bicycles real. Ernest was at the extreme edge of the spectrum, but I can’t help but to think there’s something for the rest of us to learn from him.
I know it’s not realistic to expect most inactive individuals to be motivated to jump into physical competition. I do believe, however, there needs to be a whole lot of epiphanies happening where people begin to see the need and take the step to become physically active to regain control over their health. Helping these people get involved in activities they gravitate toward, regardless of their genetic propensity to excel, is possibly the best thing we can do.
I’ve gotten a bit off track from the issue of genetic testing to identify potential responses to exercise. The exercise scientist in me is fascinated by the prospect of learning more about the genes related to specific components of fitness, but the pragmatist is concerned about the potential negative effects this could have on our increasingly overweight and obese society.
What’s your take?
Image by ghutchis (http://www.flickr.com/photos/ghutchis/124782978/).
Train Hot, Get Faster
Researchers at the Department of Human Physiology, University of Oregon have shown that training in hot conditions improves aerobic capacity — even when subsequently performing at a cooler temperature.
Using trained, competitive cyclist as subjects, the researchers had one group perform 90-minute ergometer sessions at 50% of their V̇O2max at a room temperature of 104 degrees while a control group did the same work in a room set at 55 degrees. Each group performed one session per day for 10 days while maintaining their normal training.
The results were pretty astonishing as the athletes who did heat acclimation work improved lactate threshold, V̇O2max, and time-trial performance in both cool and hot conditions, while those who did the same work in cool conditions didn’t show improvement in any of these areas.
The heat acclimation group individual data demonstrate a clear and consistent performance improvement in both the cool and hot environments, while the control group shows no tendency toward such trends for all variables.
In fact, the authors claim this is the first research to show that heat acclimation training increases lactate threshold while later performing in a cool environment.
In addition to the lower blood lactate levels measured after heat acclimation in both environments, we are the first to report that the threshold at which blood lactate levels begin to rise also is delayed by heat acclimation.
The performance gains observed are similar to what has been shown possible through sleeping at high elevations, and are expected to be retained for 1 or 2 weeks after discontinuing heat acclimation.
This is big news for the vast majority of endurance athletes living at lower elevations without access to altitude chambers or high-elevation training camps.
It will be interesting to see whether there’s an additive effect to combining high-elevation sleep with lower-elevation heat acclimation beyond what’s already been shown through “live high, train low” scenarios.
I’ve long thought that the roller sessions I did confined to the laundry room while the clothes drier was running as a teen were silly, but it’s beginning to look like I was actually onto something.
Image courtesy of Fil.A (http://www.flickr.com/photos/fbohac/4642250532/sizes/o/in/photostream/).
Source: jap.physiology.org
The New Performance Supplements — Spinach and Beets
It’s a not-so-well-kept secret in endurance sports that more and more elite athletes are loading up on nitrate-rich foods like spinach and beets to improve performance.
A recently released study from the Department of Physiology and Pharmacology, Karolinska Institutet in Stockholm, Sweden looked at the effect of supplemental nitrate on muscular force production in mice to get a better understanding of what’s going on. Researchers administered a dose equivalent to 200-300 grams of spinach or 3 to 4 beetroots in humans and tested force output.
…results show that fast-twitch muscle of Nitrate mice can be activated at a lower frequency to achieve the same force output, which would reduce the effort required for a given task. An additional benefit is that for a given torque or force output, the number of motor units needed to be recruited will be reduced without any increase in the time taken to achieve the target force.
This is extremely cool as beets and spinach are already loaded with nutrition for good health, so consuming greater amounts is a good thing. Now we know can improve our health and performance at the same time. As the researchers noted, the quantities we’re talking about can realistically be included in a healthy diet.
This is also interesting from a nutritional perspective since several leafy green vegetables are high in inorganic nitrate and the amount of nitrate used in the present study can be easily achieved by adopting a ‘green’ diet.
Now I know some readers will be thinking what I did at the first mention of beets — yuk! I can’t think of anything I found more repulsive as a child than canned beets. The thought still sends chills down my spine.
The good news is that beets don’t have to taste like that. They can be boiled, roasted, baked, steamed, microwaved, and even eaten raw. My usual route is to add raw beet, and spinach, to my breakfast smoothie.
Here’s my current favorite recipe.
- 1 cup OJ
- Large handful of baby spinach (about 40 grams)
- 1/2 large beetroot
- 4 frozen strawberries
- 1/2 cup frozen blueberries
- 1/3 cup crushed ice
- 1 scoop whey protein (yields approx. 20 grams protein)
Chop the beet into smaller pieces and blend it and the spinach OJ on high to liquify as much as possible, then blend in the frozen ingredients, and finally mix in the whey protein on the slowest setting to avoid introducing excess air into the smoothie. If your blender lacks adjustable speeds, simply length or shorten the blending times to get the desired effect.
As for taste, Chocolate-flavored protein powder works well, although lately I’ve been using strawberry-flavored protein and it gives a nice, lighter overall flavor.
Now that you have at least one easy way to eat your beets and spinach, give it a try and let me know what you think in terms of taste and performance benefits. Most people will need to increase consumption of nitrate-rich foods for at least 3 to 7 days to begin seeing and feeling a benefit, so stick with it.
Image by ulterior epicure (http://www.flickr.com/photos/ulteriorepicure/76130749/sizes/o/in/photostream/).
Source: jp.physoc.org
Back Away from the Twinkie, Fatty
I often encounter dietary recommendations by ‘experts’ who recommend that endurance athletes focus on achieving their ideal bodyweight through training alone, and not by restricting caloric intake. While this may work for some, there are plenty who are left dissatisfied.
Now there’s new research which points to dietary intake playing a greater role than physical activity when it comes to being lean.
Researches traveled to Tanzania and examined an indigenous hunter-gatherer tribe to document their energy expenditure and level of physical activity. Due to the tribesmen’s highly active lifestyles, researchers naturally expected that they burned more calories than the in industrialized, Western nations.
Surprisingly, after body size was taken into consideration, these tribesmen burned roughly the same quantity of calories as sedentary Westerners on a daily basis, even though they were much more active. By all accounts they should have burned more calories, but didn’t. Their resting metabolic rates apparently slowed in compensation.
The researchers concluded that this points to the typical highly-processed, calorie-laden Western diet as the cause for our rapidly increasing obesity.
Our results indicate that active, “traditional” lifestyles may not protect against obesity if diets change to promote increased caloric consumption. Thus, efforts to supplement diets of healthy populations in developing regions must avoid inundating these individuals with highly-processed, energy-dense but nutrient-poor foods.
This isn’t to say that one shouldn’t lead a physically-active lifestyle. Aside from the abundant health benefits, it’s part of being an endurance athlete. Rather this research indicates that our bodies may adapt to high physical workloads by decreasing overall metabolic rate — in essence we get more metabolically efficient as we do more work.
While this is good for those who want to be able to cover greater distances in a shorter time, it’s not so good if you’re trying to get leaner without modifying your eating habits.
If you’re not as lean as you realistically believe you should be, it’s time you put as much effort into eating better as you do into training and racing. Just look at it as another form of training as your performance will undoubtedly improve.
Source: plosone.org
Hydrating with Mineral Water
by Brian Maslach
With all the research on different hydration solutions lately, one particular study caught my attention as it touched upon something I’ve been doing for a while now — drinking mineral water to improve hydration and pH balance.
Researchers in Italy compared the use of a high calcium and bicarbonate mineral water versus a low mineral-content water and found the following.
…mineral water intake is correlated with the increase of urinary pH and with a lower urine specific gravity in amateur athletes, therefore it may be a valuable nutritional vector for influencing hydration status in athletes.
In other words, their research revealed that subjects consuming mineral water were better hydrated and had an increased capacity to retain water after exercise.
Anecdotally, I find that I feel better and seem to recover faster when consuming a liter or two of Pellegrino or Whole Foods Sparkling Mineral Water throughout the day. I also find that despite the natural carbonation I’m able to consume a greater volume of fluid without feeling bloated or uncomfortable - a good thing when trying to rehydrate after a long ride on a hot day. I haven’t tried using mineral water during training, although I plan to run a trial replacing half of my normal electrolyte replacement drink with it soon.
To further increase the alkalizing property of mineral water, and give yourself a bit more variety, add a little natural lemon juice.
For more on Supplementation of Acqua Lete® (Bicarbonate Calcic Mineral Water) improves hydration status in athletes after short term anaerobic exercise check out http://www.jissn.com/content/9/1/35/abstract.
Image by jirhnidek (http://www.flickr.com/photos/jirihnidek/3859286747/sizes/z/in/photostream/).
Source: jissn.com
Fish Oil Protects Against Allergies
by Brian Maslach
New research published in Clinical and Experimental Allergy adds to the mounting list of benefits to consuming fish oil. This time researchers looked at the the effects on infant immune function after administering a fish oil supplement.
Researchers concluded,
Postnatal fish oil supplementation increased infant n-3 polyunsaturated fatty acid (PUFA) levels and associated with lowered allergen-specific Th2 responses and elevated polyclonal Th1 responses. Our results add to existing evidence of n-3 PUFA having immunomodulatory properties that are potentially allergy-protective.
In other words, the researchers confirmed that the fish oil supplement administered was absorbed by the infants, and that the chemical responses associated with certain allergies was lowered.
Of particular interest due to my own issues was that the researchers saw significantly improved effects related to dust mite and milk protein allergies among the fish oil supplemented group. Anecdotally, my dust and dairy allergies seem to worsen when I’m not consuming fish oil regularly.
Whether it’s to potentially lessen allergies, improve cardiovascular health, reduced damage from endurance training, or maintain a leaner physique, everyone should be either consuming fatty fish regularly (at least twice per week) and/or supplementing with a high-quality fish oil supplement.
Image from Andrea Pokrzywinski (http://www.flickr.com/photos/andreagp/1122613434/).
Back to the Future?
by Brian Maslach
If you’ve been around cycling long enough you might remember the days when bananas were customary fuel source found in jersey pockets.
Well, a new research study titled Bananas as an Energy Source during Exercise: A Metabolomics Approach revisits this idea by examining the effects of consuming only bananas and water versus a standard 6-percent Gatorade solution during a 75 kg time trial.
The authors noted:
In conclusion, in this randomized, crossover study, cyclists ingesting BAN or CHO at a rate of 0.2 g/kg carbohydrate every 15 min (and one 0.4 g/kg carbohydrate dose pre-exercise) were able to complete 75-km cycling trials with no differences in performance measures.
CHO (carbohydrate) was the 6-percent solution of Gatorade.
It’s not all that surprising that there wasn’t much difference between the Gatorade and Banana groups as Gatorade is a dated formula that hasn’t been significantly updated since it’s development in the 1960s.
Granted, bloating was a negative effect experienced by some of those consuming only bananas due to the quantity required per session (6 to 7) and their relatively high fiber content. Personally, I can’t tolerate feeling bloated while training or racing, and I certainly wouldn’t want to carry 6 bananas while riding. However, there’s no reason bananas can’t be used in conjunction with other natural energy sources to fuel your physical endeavors.
It’s unfortunate that people have been brainwashed through million-dollar marketing campaigns to believe that florescent-colored drinks loaded with processed sugars are superior to the natural alternatives they are intended to replace.
It’s worth noting that the vast majority of carb/electrolyte formulas available today are simply revisions on the original Gatorade formula. Label inspection usually reveals a blend of cheap, highly-processed carbohydrate sources: sucrose (table sugar), fructose, dextrose, and/or maltodextrin. Sometimes one or more of these may be labeled under a trade name to differentiate it from other products. Other products will use organic sources of these, which is commendable, but the effects remain the same.
Image from allaboutgeorge (http://www.flickr.com/photos/allaboutgeorge/6590587673/sizes/z/in/photostream/).
Page 1 of 3
