I've had a couple of people ask about one of my long race habits, so I figured it's time for another Seems Like Science post to talk about it.
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| Disclaimer: I'm neither scientist nor health professional |
If I recall correctly, the first time I used vitamin B12 oral spray in a race was during my ill-fated attempt at the Foxtail 100mi in 2019. To be clear, I've used quick-dissolving sublingual vitamin B12 tablets as a regular supplement for daily life for many years due to a history of anaemia. I'm not going to discuss that application in this post: this is purely an exploration of liquid oral B12 usage in the context of a long race, which I will define loosely as 8+ hours in duration.
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| This is the specific product I have used, though I don't think brand is important. This is in the form of methycobalamin, though, which may be a more easily retained by the body - but not necessarily - than synthetic cyanocobalamin |
I spotted this stuff on the grocery store shelf at one point in early 2019 and picked it up with a theory that I might be able to use it during races - at the time, I think I paid about $12 for the bottle (which is small enough to easily fit in a drop bag or hydration vest. I based this on a couple of factors:
- Vitamin B12 is required to produce functional red blood cells, and since running actually destroys red blood cells (there's a real syndrome called "footstrike anaemia" - the result of footstrike hemolysis, or red blood cells being crushed by the impact of your feet hitting the ground - that can result), supporting the production of new ones is important
- Vitamin B12 contributes to the maintenance of healthy nerve cells, and running relies on a complex pattern of movements that must be relayed to the muscles via the nervous system
- Vitamin B12 also plays a major role in energy metabolism: converting food into glucose, which can then be used by working muscles to finally convert the glucose into forward motion
- Energy drinks (which I will state here that I do not use) frequently include B-vitamins due to their known role in promoting metabolism
- Symptoms of B12 deficiency - like fatigue, shortness of breath, and digestive issues - are all detrimental to athletic performance
Now, there are a number of reputable sources that state there is no clinical evidence to support an increase in athletic performance based on B12 supplementation in the absence of a deficiency, but maintaining B12 status relies on the ingestion of animal foods - fish, meat, poultry, eggs, and dairy - or supplements. Fun fact: the natural form comes from bacteria that inhabit these - there is a synthetic vegan form (cyanocobalamin, mentioned above). Animal food sources, however - whether or not you choose to eat them in daily life - are difficult to digest when running, and are thus typically not part of race-day nutrition. This may not result in deficiency for events lasting one day or less (vegetarians and vegans will be more prone to deficiency unless they take supplements or eat fortified foods), but my interest in the oral spray was more geared toward races that last more than a day and are therefore more likely to deplete the body's stores. While studies have been performed on athletes including those classed as "endurance" competitors, there is a wide range of events that are considered "endurance" sports - which may include races shorter than 1 hour, and seldom longer than 5 hours - I am not aware of any that have studied very long distance runners, whose metabolic needs and challenges vary from those in shorter competitions.
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| #ultrarunnerproblems |
The other thing I will emphasize is that - being a water-soluble vitamin - B12 (which is also just known as cobalamin, as it is cobalt-based) is generally considered safe in very high doses, as excess is simply excreted in urine. I am not aware of any studies that examine the effects of dehydration - which can, of course, be another effect of very long races, as it can be impossible in hot weather to drink enough to match sweat losses - on the body's ability to excrete excess B12, so that will fall outside the scope of this post.
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| If anyone is interested in funding, equipping, and staffing ill advised labs to study this stuff, please message me! |
So, being reasonably assured I wouldn't do myself any harm by trying, I started spraying this stuff in my mouth at events. It tastes like raspberry and delivers 500mcg - which is a LOT compared to the recommended daily intake of 2.4mcg for adults, even with an estimated absorption rate of only 2% for that dose - of methylcobalamin per spritz.
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| But hey - why use a scalpel when you can use an axe? |
(Let's not do anything silly like try to sue me for describing an off-label use of a readily available vitamin if you manage to give yourself a headache, nausea, or GI distress from taking too much, ok?)
Now, Foxtail - for many reasons - was a poor test of the possibilities that vitamin B12 supplementation might hold. I didn't really run anything particularly long for awhile afterward, so the bottle of spray lurked in with some other rather neglected race nutrition stuff on top of our microwave for quite awhile. I found it, though, just before what was possibly the perfect test event: the 2021 Three Days in the Park 72hr.
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| Going in with a torn hamstring, I'd take any little advantage I could get! |
I didn't use any the first day, but finally realized it was there around 3:30pm on Friday - approximately 30.5hrs in. I had a spritz with a cup of coffee, and within 20mins it was like I'd swallowed the human equivalent of jet fuel! I used this combination again at around 3am Saturday morning, with the same effect: despite being worn and beaten, about 20mins later I'd go from dragging myself along to marching with purpose, and the effects would last for anywhere from 90mins to 2hrs.
I continued to use the B12 - which had expired in August 2020, but gave me no ill effects - in conjunction with coffee through the end of the 72hr, after which it retired to the top of the microwave once more.
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| I do not recommend using expired nutritional supplements, but that doesn't mean I won't do it myself. |
While having the coffee + B12 combo as an ace in my pocket was great, I wondered what effect the spray might have on its own, and I've had a number of chances to experiment with it this year. I knew I was in for a rough day at the Pick Your Poison 50k back in April (because running up and down a ski hill - with 4 major climbs per 12.5km lap - is heckin' hard), so I tried some before the start, and then in between my 2nd and 3rd laps. There was no noticeable energy boost, but I was able to push my undertrained and kind of jacked-up body through almost 9 hours of reletless hills and run it in to the finish. I don't have a record of having used any at Sunburn Solstice this year, but that was also a sub-8-hour event, and the 50k I mostly walked at Foxtail this year was only just over 8hrs.
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| I had one more good, solid experiment opportunity left, though. |
My real proof of concept came at Three Days in the Park this year, where I ran the 24hr. I started using sprays of B12 from late afternoon (around 4:30pm, or 7.5hrs in) and took 5 spritzes throughout the event. At no point did I actually have it in conjunction with a cup of coffee (though I did drink 2 of those, around 2am and 5:30am), but I believe it was a contributor to my rather steady energy levels throughout the race. Of course, steadily taking in calories and water are bigger factors - fuel and hydration will always be two of the biggest drivers in any event longer than 3 hours - but I was able to stay clear-headed and alert much longer than I expected before beginning to use the marginal amounts of caffeine that I took in, and theorize that the regular doses of B12 assisted my body in processing the nutrition I was taking in to ensure my muscles were supplied with glucose to keep me moving.
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| I have no way of confirming this empirically except through further experimentation |
I understand that some weak anecdotal reports are not the same as evidence, but my high-demand race experiences using B12 have been positive enough for me to continue to add it as a supplement in long competitions. Even if it's a placebo effect - in the absence of any harm - why not seize a tiny possible advantage in races when I am pushing myself to my limit? My worst case scenario is likely some higher-priced pee, and even a slight improvement in mentality through the course of 24hrs can have a major ripple effect on the mileage I'm able to achieve. A happy runner has more energy to carry them down the trail than an unhappy one, and if the B12 does actually keep my red blood cell counts healthier or help me convert the food I'm eating into forward motion, I'd be foolish not to seize that advantage.
So, for anyone who has managed to make it through all that: I would absolutely be interested to hear your thoughts or lived experience with (legal) supplementation in races. This ongoing experiment has had no deleterious effects that I've noticed, and potential realized benefits with a very low up-front cost and little risk of side effects. Will you try B12 for your next ultra? Have you tried another supplement to good effect, or fallen victim to a side effect of a supplement gone wrong? Let me know!
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| I can't be the only one out there trying weird stuff based on wild theories! |
