Looking for an Edge, What Actually works?
Dr. Jeffrey Sankoff tells us the best evidence-based performance enhancers
Dr. Jeffrey Sankoff
My name is Jeff Sankoff. I am a triathlete, a triathlon coach and an emergency physician based in Denver, Colorado. For the past four years I have been producing the TriDoc podcast a show in which I work hard to help endurance athletes cut through the marketing hype to understand the science that underpins so many of the products and programs that are thrown at us every day.
As athletes, we are all looking for ways to leverage that science to find an edge. Can this one thing make us train more effectively than our competition? Can that other thing make us recover better than them? Together, will these things make us better at racing than we would be without them? These are sometimes hard questions to answer and when slick advertising campaigns are paired with science, the results are often misleading, confusing, and difficult to separate from the truth.
Over a hundred and twenty episodes, I have looked at various products and training or recovery regimens that have been promised by all manner of companies, coaches and athletes to be the best legal ways of enhancing performance and in almost all cases I have found that the claims are not backed up by the science.
Most things that I have investigated are simply not worth your money because the claims being made are unsupported by scientific research or the actual performance gains are too small to amount to anything measurable in the real world (e.g.: bicarbonate supplementation, magnesium, CBD, continuous glucose monitoring, compression clothing).
A smaller number of the things that I have reviewed don’t necessarily provide any significant tangible physical benefits but do provide measurable psychological benefits and fall into a category that I think of as luxury items. These are things that are often expensive, but that people really enjoy or think they are getting benefit from even though the science suggests that all of the benefits are only in their heads (e.g.: pneumatic compression garments, massage guns, cold water immersion). I do not want to diminish the value of these items in any way. Psychological benefits are very real and if people derive pleasure or positive feelings from something I am all for it.
The smallest number of things that I have reviewed fall into the category of things that actually work and live up to the claims of their manufacturers or supporters. This is a very short list but everything on here has the science to back up the notion that using them or following these protocols will boost your performance legally.
Here then, is the list of things that I have found to be worthwhile investing in to maximize your training, recovery and racing to the highest level.
I recognize that it may be a little bit disappointing that the first thing on this list is something that you do rather than something you take but tapering for a race is by far one of the easiest things that you can do to dramatically impact performance. First studied in the early nineties, high quality randomized controlled trials have demonstrated that well designed tapering as part of a training program can improve race day performance by as much as 6%. Physiologically, tapering improves tissue glycogen levels, VO2 max plasma volume and red cell mass.
Studies have even helped delineate what the ideal taper should look like. Athletic performance in a race is seen to be best after a taper that is two weeks long, has a decrease in volume from pre-taper training of 50% but maintains high intensity.
The second thing on this list is also something that you can do rather than something you can take. And that is…
I think that it is well understood by all that a well-rested athlete is an athlete who is better set up for a good performance. It should come as no surprise then that there is an abundance of scientific research that bears this out. Numerous studies have been done on sleep and athletic performance and as a result we have a pretty good idea how and why the two are related:
Decreased sleep leads to earlier perception of exhaustion
More sleep results in higher levels of muscle glycogen
Studies of athletes who are sleep restricted demonstrate 5% reductions in cycling time trial proficiency.
Learning and executive function are impaired by less sleep.
This is associated with a higher risk of traumatic injury.
Less sleep is consistently associated with higher injury rates.
Sleep is also associated with immune function such that improved sleep is related to improved immune function.
We are finally up to some items that you can ingest to see a performance benefit and everything on this list is 100% legal so fear not.
Although it may seem like the opposite of sleep, caffeine has some remarkable and reproducibly proven effects on endurance performance. While it is not completely clear how the drug exerts its effects to achieve the results that it has, the ingestion of caffeine most definitely has a small but significant effect on endurance performance. Studies have shown that doses between 3-6 mg/kg can give a 2.9% boost in mean power output and 2.2% reduction in time trial performance.
How you get your caffeine, how much you take and how often you take it are a bit less straightforward, but one thing is clear; almost everyone is using it so caffeine is less likely to improve your performance over others than it is to just get you on par with them!
4 mg/kg of caffeine comes out to around 300 mg. To get that you would need to drink three cups of coffee, four Red Bull, seven cans of Coke or 3 Maurten gels with caffeine.
Keep in mind that women and older age correlate with slower metabolism of the drug so in those circumstances it doesn’t need to be taken as frequently over the course of a race. Furthermore, caffeine taken in too high an amount can lead to some unpleasant side effects so be sure to practice with the amounts you plan to use when racing and ensure you don’t overdo it on course.
Beets have long been studied for their health benefits and have been recognized for their ability to improve cardiovascular health and lower blood pressure. The ingredient in beetroot juice that has these effects on heart health is the same thing that confers benefits on performance, nitrates.
Beetroot juice is very highly concentrated in nitrates that are converted to nitrites that then has the effect of increasing blood flow to muscles, improving mitochondrial efficiency and enhancing skeletal muscle function.
The scientific evidence for beetroot juice has been compelling but is very sport specific. For example, almost all the positive effects are reported in cyclists. None of swimmers, rowers, kayakers or runners have seen any of the positive impacts associated with beetroot juice as cyclists have. Furthermore, the effects of beetroot juice is quite short lived. Cyclists tend to show benefit in time trials lasting up to 20 km (2.5% shorter duration) but those benefits are lost when distances reach 50 km or longer.
There are a couple of other caveats related to beetroot juice the first being that you need a lot of it to get the reported effects and most of the commercially available products do not contain anywhere close to what is needed. Another consideration relates to the timing of effect. Beetroot juice must be taken at least ninety minutes before exercise with peak effects seen 2-3 hours post-ingestion.
Finally, a growing body of evidence suggests that beetroot juice does not confer any observable benefits to women. While the health-related effects are likely still valid, women have naturally higher circulating amounts of nitrite and the supplemental amounts acquired from ingesting beetroot juice does not seem to be enough to overcome this in women making supplementation of no real benefit to endurance in this sex.
The final supplement for which I have found good evidence to suggest a true performance benefit is also plant based:
Spirulina is a naturally occurring, abundant blue green algae and is easily cultivated and found worldwide. It contains a wide variety of minerals and other nutrients in relatively high quantities. 7 g of spirulina contains:
4g of protein
11% of the RDA of thiamine (B1)
15% of the RDA of riboflavin (B2)
4% of the RDA of niacin (B3)
21 % of the RDA of copper and
11% of the RDA of iron
omega-3 fatty acids, complex antioxidants
A lot of health benefits have been attributed to spirulina but none have been rigorously studied. Performance benefits have received more scrutiny and the results have been impressive.
Using spirulina has been associated with an increased time to exhaustion for a treadmill test by 7%. Cyclists using spirulina have demonstrated improved performance with lower heart rates and improved VO2 max. Other studies have shown that cyclists can demonstrate better performance at both sprint and longer TT tests.
Finally, lab studies with spirulina have shown cyclists can have lower levels of lactate production, lower heart rates for the same effort and higher peak powers. All this from a lowly single celled organism!
At the end of the day, nothing you buy is going to be a miracle, there is simply no substitute for doing hard work, maintaining consistency and eating right. However, if you are doing all of those things and still hoping to find ways to extract a few marginal gains here and there, you wouldn’t really go wrong by improving your sleep habits, incorporating caffeine in to your diet if you don’t already, supplement with concentrated beetroot juice if you are a male and add spirulina to your daily diet in the form of caplets, powder or frozen cubes. And of course, incorporate a well-structured taper in to your pre-race training plan.
To hear more reviews of more than a hundred other supplements and devices that I have investigated, subscribe to the TriDoc podcast, wherever you get your listening content. Or, visit www.tridocpodcast.com and learn how you can subscribe or download individual episodes.
Train hard, train healthy