There is still no “must-have” supplement for endurance athletes.
Written by: Matt Fitzgerald
Creatine works. Dozens of studies have clearly proven that daily supplementation with creatine monohydrate and other forms of creatine enhances gains in muscle strength and size in response to weightlifting and also boosts maximum and repeated sprint speed. There are extreme anti-supplement voices who point to the small minority of studies showing mixed or negative results, but they are not taken seriously by athletes in strength and speed sports, who almost universally use creatine.
Influenced by the research, I started using creatine during the hardcore weightlifting phase of my athletic life. It was the closest thing to a perfectly controlled experiment of one. My training routine was unchanging. I did the same workouts week after week, month after month. The only thing that changed was that I started taking creatine. In the months preceding supplementation, my strength had remained steady, as one would expect in a consistent but non-progressive training program. Within weeks of starting supplementation, all of my lifts increased substantially.
I was sold. And not only was I sold, but creatine became my standard for future supplementation. After transitioning back into endurance sports, I needed to see research as compelling as that which supported creatine to be motivated to try any supplement purported to enhance endurance performance, and when I did try one, I needed to experience results that were measurably significant, like those I got from creatine.
In twelve years, not a single supplement has passed even the first test. Countless supplements have shown promising results in animal experiments, only to fail in human experiments, or have seemed to boost endurance performance in early human trials (usually funded by the maker of the supplement being tested), only to fall flat in subsequent validation studies. Advocates of the individual endurance supplements will swear that the positive studies constitute sufficient evidence to declare that they work, but when you compare the full body of research on these supplements to that which stands behind creatine, it’s not even close.
Let’s look at just a few examples.
Beetroot Juice – Beetroot juice is the latest miracle performance supplement for endurance athletes. Animal and human studies have shown it has a positive effect on endurance performance. It’s actually not beetroot juice per se—it’s the dietary nitrates in beetroot juice that produce this effect. Regardless, I don’t drink beetroot juice or take nitrate supplements. Why not? Because only two relevant studies have been done, and both involved non-athletes. If I had a nickel for every supplement that enhanced exercise performance in people who don’t regularly exercise, and has no effect in those who do, I’d be retired.
CoQ10 – Coenzyme Q10 is a coenzyme present in every human cell that plays a critical role in aerobic metabolism in the mitochondria. Given that function, it made sense to test whether CoQ10 supplementation enhanced aerobic capacity in endurance athletes. A few studies have shown a very modest benefit, many more have shown none. When that is the balance of findings, you know to trust the studies showing no benefit. Supplements that really work show significant benefits in 90 percent of studies, not barely noticeable benefits in 50 percent of studies.
Cordyceps – Cordyceps is a mushroom extract used in herbal medicine. It is purported to boost energy and endurance and has become popular with endurance athletes lately. Unfortunately, it’s a waste of money. A 2005 study involving cyclists found that a supplement containing cordyceps and rhodiola had no effect on performance.
Resveratrol – Resveratrol is a compound in red wine that belongs to a class of nutrients called polyphenols, many of which function as antioxidants. Resveratrol made a big splash a few years ago when animal studies showed it had a huge effect on endurance. Too bad humans would have to consume 1.5 grams of pure resveratrol per day to match the dosage that proved effective in mice, or about 37 times the amount of resveratrol contained in the typical resveratrol supplement currently on the market.
Rhodiola – Rhodiola rosea is an extract from a plant that grows in mountain environments. It is purported to enhance mental and physical performance by acting on neurotransmitters in the brain. Many endurance athletes take supplements combining rhodiola and cordyceps. We’ve already seen that such supplements are ineffective. But how about rhodiola on its own? Same thing. A 2010 study found no effect of rhodiola on performance in trained male athletes.
I am someone who is generally open to taking supplements. I also know a lot about supplements—it’s part of my job. I am also a serious endurance athlete. For these reasons, I’m a good person to look to as an example of whether a supplement for endurance performance is worth taking. I don’t take any supplements for endurance performance.
Check out Matt’s latest book, Racing Weight Quick Start Guide: A 4-Week Plan for Endurance Athletes.