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Does beta-alanine work best for older trained women? Well, according to recent research soon to be published in the Journal of Strength and Conditioning Research [1].
Beta-alanine
In the article “
which supplements do I need” I mention beta-alanine as one of the supplements for which I am willing to allocate part of my supplement budget.
In short and simple terms: Beta-alanine works by increasing the store of carnosine. Carnosine reduces the acidifying effect of strength training on muscles (which is not caused by lactic acid itself, but by the hydrogen ions that lower the pH value in the muscles). Carnosine counteracts this effect by rapidly removing the hydrogen ions, thereby delaying the point of muscle exhaustion. However, carnosine itself breaks down quickly when ingested, so it hardly reaches the muscles. Beta-alanine is converted into carnosine in the body and is therefore a better way to get carnosine into your body. It’s a bit like citrulline is a way to get arginine.
We are mainly talking about energy expended in the lactic acid system where beta-alanine adds value [2].
Beta-alanine works better in women
Beta-alanine works differently in different people. Trained men, for example, benefit more from beta-alanine than untrained men, who according to one study have no benefit at all [3,4,5].
The effect of beta-alanine also varies between women and men. Women naturally have less carnosine in their muscles than men [6]. Supplementation with beta-alanine, which is then converted into carnosine, therefore has a proportionately greater effect on the amount of carnosine in the muscles in women [7]. Carnosine levels also decrease as people age, on average from 47 years old [6]. When you add this together, you naturally conclude that older, trained women should benefit the most from beta-alanine.
Research: Beta-alanine in older female athletes
Researchers from the University of Arkansas found it likely strange that no studies had been conducted on the effects of beta-alanine with this population [1].
For their study, they used 22 female cyclists with an average age of 54, who had at least 2 years of experience and cycled at least 3 times a week. They divided them into two groups; one group received 8 grams of dextrose, the other group received 8 grams of dextrose plus 800 milligrams of beta-alanine. They received this four times a day, for 28 days. In total, the test group received 3.2 grams of beta-alanine per day. Based on questionnaires about their daily diet, the researchers were able to determine that there were no differences in daily calorie intake or the distribution of these calories across the various macronutrients carbohydrates, protein, and fats.
The women were tested on isokinetic strength (muscle contraction at a constant speed using a device) and grip strength, before the test, after the test, and weekly in between. Grip strength was measured by how hard they could squeeze a handle for 5 seconds (isometric strength). Isokinetic strength was determined by doing a leg extension curl combination with the Biodex System II Isokinetic Dynamometer. They did 50 repetitions per test. Both tests were done weekly to measure progress. At the start, there was no difference in both types of strength between the two groups.
Results
Beta-alanine had the most effect on leg exercises, particularly in the last 1/3 portion of the exercise. This is not surprising because this is where acidosis can occur, which beta-alanine is supposed to counteract. For example, average peak power increased by over 8% with beta-alanine compared to just (almost) one and a half percent in the placebo group. The total amount of “work” that could be performed increased by 24% compared to almost 17 percent in the placebo group.
When comparing BA (red. beta-alanine) and PLA (placebo), at the 28 day time point, average peak torque (F = 7.398, p = .014; 8.1% vs 1.4% change, respectively) and total work performed during the final 3rd of exercise (F = 5.942, p =16 .024; 24.0% vs -16.8% change, respectively) significantly increased from baseline.
Grip strength did not increase with beta-alanine, but that was to be expected since the test lasted only 5 seconds. Too short for acidosis (ATP system instead of lactic acid system). Beta-alanine also had no effect on body fat percentage.
Conclusion
The researchers from Arkansas have successfully demonstrated that beta-alanine works in older experienced women. Compared to other studies where no or less results were achieved with sometimes higher dosages in (untrained) men, this strengthens the assumption that trained women respond better to beta-alanine, especially older, trained women.
References
- Glenn J.M. et al. Effects of longitudinal beta-alanine supplementation on isokinetic exercise performance and body composition in female masters athletes. Journal of Strength andConditioning Research Publish Ahead of Print DOI: 10.1519/JSC.0000000000001077
- Hobson, R, Saunders, B, Ball, G, Harris, R, and Sale, C. Effects of β-alanine supplementation on exercise performance: A meta-analysis. Amino Acids 43: 25-37, 2012.
- Derave, W, Özdemir, MS, Harris, RC, Pottier, A, Reyngoudt, H, Koppo, K, Wise, JA, and Achten, E. β-Alanine supplementation augments muscle carnosine content and attenuates fatigue during repeated isokinetic contraction bouts in trained sprinters. J Appl Physiol 103: 1736-1743,2007.
- Kendrick, IP, Harris, RC, Kim, HJ, Kim, CK, Dang, VH, Lam, TQ, Bui, TT, Smith, M, and Wise, JA. The effects of 10 weeks of resistance training combined with β-alanine supplementation on whole body strength, force production, muscular endurance and body composition. Amino Acids 34: 547-554, 2008.
- Bex, T, Chung, W, Baguet, A, Stegen, S, Stautemas, J, Achten, E, and Derave, W. Muscle 10 carnosine loading by beta-alanine supplementation is more pronounced in trained vs. untrained 11 muscles. J Appl Physiol 116: 204-209, 2014
- Everaert, I, Mooyaart, A, Baguet, A, Zutinic, A, Baelde, H, Achten, E, Taes, Y, De Heer, E, and Derave, W. Vegetarianism, female gender and increasing age, but not CNDP1 genotype, are associated with reduced muscle carnosine levels in humans. Amino Acids 40: 1221-1229, 2011.
- Stegen, S, Bex, T, Vervaet, C, Vanhee, L, Achten, E, and Derave, W. Beta-alanine dose for maintaining moderately elevated muscle carnosine levels. Med Sci Sports Exerc 46: 1426-1432, 2014.
