For many, the extent of knowledge surrounding the performance supplement beta alanine is that “it’s in pre-workouts and it makes my face tingly”. But the research runs much deeper than that.
So firstly, what is beta alanine? It’s a modified version of the amino acid alanine and used as a performance aid mainly because of its implications with increased muscle endurance. It’s a group A supplement as classed by the AIS, meaning it’s use HAS been supported by research and that athletes are permitted to take it.
Supplementing daily for 4-8 weeks has been linked with improved performance in exercise efforts lasting 1-6 minutes. Researchers have also reported subjects being able to perform one or two additional reps in the gym when training in a range of 8-20 reps, so closer to that endurance end of the spectrum.
So how does it work?
When beta alanine is ingested it’s converted into carnosine inside the muscle by joining it to another amino acid, histidine. So the benefits we are about to talk about aren’t coming from the action of the beta alanine itself, but actually from increased muscle carnosine. One of the main roles of intramuscular carnosine is to maintain the acid base equilibrium by buffering H+ ions (reducing perception of fatigue), so we can begin to see why elevated muscle carnosine stores could be involved in performance benefits. It’s released from the cell to perform its buffering action when a drop in pH is sensed i.e. during exercise. We see higher concentrations of carnosine in type 2 muscle fibres which experience the highest levels of H+ accumulation, giving more support for carnosine acting as a buffering agent. A study also showed that when isolating a muscle sample and making it absent from carnosine you get a rise in acidity.
Since muscle acidosis probably contributes to the onset of fatigue during high intensity exercise, increasing muscle carnosine by taking beta alanine should theoretically improve buffering capacity and therefore delay the onset of fatigue.
But the buffering of H+ is just one explanation for why we might see improved performance in activities where lactate build up is the limiting factor, there are actually several other potential mechanisms associated with elevated carnosine stores that could help explain performance improvements by supplementing with beta alanine.
High carnosine levels cause an increase in sensitivity of calcium release channels which could improve the force of muscle contractions particularly when under fatigue. Carnosine also has antioxidant properties, so it may reduce free radicals produced during exercise, with high levels of free radicals being implicated with fatigue. Carnosine also causes vasodilation, so improved muscular supply of oxygen and nutrients, with increased waste removal might also play a part. Then finally, a study which looked at American Football players found that beta alanine was able to reduce the perception of fatigue during high intensity exercise, so this could either be an independent benefit of its own, or maybe a downstream effect of one of the other mechanisms. Keeping all that in mind, performance improvements from supplementing with beta alanine may be explained by one or a combination of all these factors.
Why not just supplement with carnosine or histidine?
Research has shown that carnosine can’t enter muscle cells to a great amount., and we don’t need to supplement with its other substrate histidine, because histidine peptides are already stored in large amounts in muscle cells. So it’s pretty clear that it’s the actual beta alanine that is the rate-limiting factor in muscle carnosine production.
Gimme the dose
In terms of dosing protocols, we’ve seen significant increases in carnosine stores when taking 2-5g of beta alanine daily for 2-8 weeks. In one study after 8 weeks of 1.6g of beta alanine per day carnosine stores increased by 35% in the gastrocnemius, and after 3.2g a day for 8 weeks, stores increased by 44.5%. So the cellular changes we are talking about are pretty substantial.
An important thing to note is that dosing is not time dependent, which is interesting considering there are hundreds of beta alanine mixtures labelled as “pre-workout” supplements. The rise in carnosine from beta alanine is not acute; it’s cumulative, so intermittent use of these supplements just before exercise is pretty useless.
One side effect (and possibly the most well appreciated feature) of beta alanine is a mild paraesthesia – a tingling in the skin of the face and arms – but this is harmless and can also be avoided by doing split doses across the day.
Should I take it?
Reading a lot of the studies out there, the increase in carnosine storage from beta alanine dosing is most beneficial for efforts lasting between 1 and 6 minutes, above and below that range not many benefits are seen. This is likely because this duration of exercise, assuming it’s close to maximal, usually results in some cell acidosis where improved buffering capacity could be useful.
From the available literature we know beta alanine is effective for rowing 2000m, running the 1500m and 3000m, and swimming the 400m and 800m as these would all be considered middle distance events with exercise lasting between 3-10 minutes. But what about pumping the bench press for 8-12 reps? Being so prevalent in bodybuilding supplements surely it would have notable benefits? Unfortunately, the research is less clear on beta alanine for hypertrophy-focused resistance training, with some studies showing a benefit, some showing none. Typically, the benefits are also only observed in the higher rep ranges characteristic of endurance type training where local fatigue build up is a limiting factor. The research is also unclear whether the paraesthesia has a positive psychological effect on performance, as anecdote would suggest.
So, if you’re a middle-distance athlete, dose up, it’s going to shave some seconds off your time. If you’re just trying to get jacked, feel free to take it with little downside, however the performance benefits are likely to be marginal. Nonetheless, if you are trying to obtain the endurance benefits of this supplement you must take it chronically, taking it 30 minutes before training 4 times a week has little merit if any.