Tag: supplements

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My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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More research from Andrew Jones’s group at the University of Exeter on the endurance-boosting effects of beet juice, which they previously reported can extend time-to-exhaustion by about 15% (equivalent to about a 1% improvement in a race over a specific distance), in a forthcoming paper in the Journal of Applied Physiology (press release here).

The most interesting new twist: they’ve developed a way of filtering the nitrates out of beet juice using an “ion-exchange resin,” allowing them to create a placebo form of beet juice that is identical to the real thing in every way except for the absence of nitrates. They’ve hypothesized that it’s the nitrate in beet juice that reduces the “oxygen cost” of running and other endurance exercise — i.e. you burn less energy to produce the muscular force needed to propel yourself forward, allowing you to last longer. But beet juice has a whole bunch of potentially beneficial ingredients, including big names like quercetin and resveratrol, so they needed some way to check which ingredient was actually making the difference. The new double-blinded study does that nicely: the nitrate-free beet juice had no effect on subjects, while the regular beet juice lowered blood pressure and improved performance in various endurance running tests.

One other new result is that they tested low-intensity exercise as well as high-intensity. Sure enough, they found that the oxygen cost of walking was significantly decreased after just four days of drinking 500 ml of beet juice per day.

For senescent populations or individuals with pulmonary, cardiovascular or metabolic disorders, [they write,] a reduction in the O2 cost of daily activities might significantly improve functional capacity.

Maybe, maybe not — I’m not convinced seniors will really care about shaving 1% from their evening walk time. But for competitive athletes, the body of evidence for beet juice is getting solid enough to make me reconsider my initial skepticism. I’d like to see similar results from other labs, though.

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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One of my greatest regrets about writing this blog is that the more I dig into the evidence behind most of the supposed “performance-boosting” supplements out there, the less I believe most of them have any legitimate effect. If I never looked at the actual research, I could be popping all sorts of pills in blissful ignorance — and because I’d believe in them, they’d give me a nice robust placebo effect. In fact, I’ve toyed (mostly in jest) with the idea of suggesting that elite athletes should avoid finding out too much about the science of ergogenics, so that they can maintain the fantasy that these things work and thus get an edge from them.

But a recent study from Harvard suggests that one of my key assumptions may be false. The study (which is freely available here and described by a press release here) set out to determine whether you have to believe in a placebo in order for it to work. To that end, they recruited 80 patients with irritable bowel syndrome (IBS). Half of them received no treatment, while the other half received placebo pills to take twice daily — but they knew that the pills were nothing but sugar:

“Not only did we make it absolutely clear that these pills had no active ingredient and were made from inert substances, but we actually had ‘placebo’ printed on the bottle,” says Kaptchuk. “We told the patients that they didn’t have to even believe in the placebo effect. Just take the pills.”

To everyone’s surprise, nearly twice as many placebo patients reported relief from their symptoms (59% vs. 35%), and “patients taking the placebo doubled their rates of improvement to a degree roughly equivalent to the effects of the most powerful IBS medications.”

So what on earth is going on here? The researchers speculate that “there may be significant benefit to the very performance of medical ritual.” This isn’t a new idea — I read a very interesting book on the placebo effect a few years ago that argued, in effect, that the doctor-patient relationship is the most powerful placebo mechanism available to us. Of course, “feeling better” is not the same kind of outcome as “running faster” or “growing bigger muscles.” I’d love to see a study that investigated whether undisguised sugar pills could enhance athletic performance. What would WADA do if the results came back positive? 🙂

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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Another study on antioxidant supplements, this one from researchers at the University of Queensland in Australia, published online in Medicine & Science in Sports & Exercise.

The study was with rats: 14 weeks of supplementation with vitamin E and another antioxidant called alpha-lipoic acid, training four times a week. The antioxidants suppressed the growth of new mitochondria (the “power plants” of your cells), which is one of the primary adaptations to endurance training. One of the new wrinkles to this study compared to previous ones is that growth of mitochondria was suppressed even in rats that weren’t training, if they took the supplements.

I’ve written several times before about this area of research. The idea is that “reactive oxygen species” (ROS) are generally bad, and antioxidants fight them. But when you exercise, the ROS you produce are the “signals” that tell your body to adapt, so if you take antioxidants, your body doesn’t realize it’s supposed to adapt and get stronger (or grow more mitochondria or whatever).

The conclusions are far from clear — for instance, this study didn’t find any reduction in the benefits of endurance training from antioxidants. But given how little evidence there is that these types of supplements actually help, the potential costs certainly seem to outweigh the benefits.

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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In general, I’m not a big fan of performance-boosting supplements, in part because of some vague notions of “the spirit of sport” and in part because the vast majority of them are expensive placebos. But one of the sessions at the sports nutrition conference in Canberra earlier this week made a strong case that beta-alanine now has enough evidence to join the very, very short list of supplements with solid performance-enhancing science behind them (e.g. caffeine, creatine). The first important study of beta-alanine was only in 2006, but there have been 27 more studies since them, according to Trent Stellingwerff, a researcher at the Nestle Research Centre in Switzerland who also works with Canadian Olympic teams.

(Sorry for the delay in reporting on the sports nutrition conference — really busy week! There’s lots more to come, which I’ll post over the next few weeks.)

Basically, beta-alanine works just like baking soda to buffer pH, but does it from inside the muscle rather than outside (and, happily, doesn’t cause diarrhea). The actual buffering agent is something called carnosine, which is present in meat. When you eat meat, the carnosine is split into its two constituent amino acids (beta-alanine and histidine), which are absorbed into your muscles and recombine to form carnosine again. The rate-limiting step is the absorption of beta-alanine into your muscles, so if you take some extra beta-alanine you end up with more carnosine.

So when does this work? The sweet spot is thought to be exercise lasting between 60 seconds and 10 minutes. Studies dating way back to the 80s showed that sprinters have twice as much carnosine in their muscles as marathoners do. More recently, a Belgian study measured baseline carnosine levels in a group of rowers (i.e. without supplementation) and found that higher carnosine levels correlated to higher performance. Supplementing with beta-alanine then led to a 4.3-second improvement over ~6 minutes for the rowers.

The dosing details: unlike baking soda, it’s not a one-shot deal. Trent suggests that taking 3-6 g/day for four to eight weeks will increase muscle carnosine content by 40-50%. It then stays high for quite a while, so you can expect to continue seeing a performance boost up to a month after stopping supplementation.

For endurance athletes, there are a couple of potentially interesting wrinkles. A 2009 study in the Journal of Applied Physiology (Van Thienen et al.) found that cyclists on beta-alanine performed better in a 30-second all-out sprint at the end of a 110-minute time trial. So the buffering might help with the anaerobic demands of a finishing sprint even during a very long race, though this is just one study so far.

The other thing to consider is whether beta-alanine could help endurance athletes sustain higher levels of intense training — after all, interval sessions often include intense running within that 60s-10min sweet spot. Stellingwerff, who coaches a bunch of athletes including his wife, a 4:05 1,500m runner, gave one piece of practical advice. He said for a workout like 10x400m, athletes on beta-alanine tend to feel really good in intervals 1, 2, 3 and 4 — in fact, they sometimes feel too good and wreck the rest of the workout, so that intervals 7, 8, 9 and 10 get really ugly.

Anyway, food for thought. But as Trent pointed out, there’s no point even thinking about these kinds of supplements if you haven’t already taken care of the far more important basics of good diet and recovery and so on.

THANK YOU FOR VISITING SWEATSCIENCE.COM!

My new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Also check out my new book, THE EXPLORER'S GENE: Why We Seek Big Challenges, New Flavors, and the Blank Spots on the Map, published in March 2025.

- Alex Hutchinson (@sweatscience)

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Over the past few years, I’ve become increasingly skeptical about the benefits of taking vitamin C (and other antioxidant) supplements. On the other hand, vitamin D research has looked increasingly promising. So here’s a study from Montreal’s Jewish General Hospital that suggests I should keep my mind open:

In a double-blind clinical trial, patients admitted to the JGH were randomly assigned to receive either vitamin C or vitamin D supplements for seven to ten days. Patients administered vitamin C had a rapid and statistically and clinically significant improvement in mood state, but no significant change in mood occurred with vitamin D, the researchers discovered.

Now, this is a fairly specific population being studied, so the results aren’t generalizable. Apparently about 20% of the acute-care patients in that hospital “have vitamin C levels so low as to be compatible with scurvy,” so it’s not surprising that vitamin C helped. Ultimately, this is simply more evidence that supplements are useful for treating deficiencies; it doesn’t say anything about whether supplements provide any benefits for healthy people.