I am often asked from people why they get ‘itchy’ skin after taking pre-workout supplements. The answer lies in a common amino acid found in most pre-workout formulas called B-alanine.
B-alanine is an amino acid that has been found to improve performance in high intensity exercise. This includes competitive events lasting 1-7 minutes and repeated bouts of high intensity work like sprints and weight lifting. Current research indicates that it takes approximately 4 weeks of using B-alanine before you will gain these benefits.
Last year I conducted my own study on B-alanine to investigate the reason why it has this ‘pins and needles’ effect. In this study I asked 25 males to take different doses of B-alanine and report the side effects they felt. They reported feeling pins and needles, tickling, itching skin, flushing and/or shivering skin, and hypersensitivity and/or skin irritation. These side effects were felt on the ears, forehead, scalp, trunk, arms and back of the hands, and also on the base of their spine and buttocks.
The level of side effects was linked to body weight and those that weighed less experience more side effects. Specifically, the people who were less than 75kg experienced the most side effects.
The reason B-alanine has this effect is a complex interaction between B-alanine and the nerves on the skin. A receptor called MrgprD is expressed by a subpopulation of primary sensory neurons. These neurons exclusively innervate the skin, but do not cause any redness or swelling. This means that neural activity caused by B-alanine induced itching originates in the peripheral and not the central nervous system.
Avoiding this side effect is easy:
- The first option is to take a smaller dose which will reduce the side effects but you will need to take more doses throughout the day to make sure you get enough B-alanine to gain the benefits.
- However the best option is to replace your current pre-workout formula with a new slow-release version of B-alanine supplement developed in Switzerland. Early research shows that this new slow-release B-alanine has all the benefits and no tingling side effects.
Vince Kelly is an Associate Lecturer at the School of Human Movement Studies at the University of Queensland and has worked for over 15 years in elite sport as a strength and conditioning coach. He is currently completing his PhD examining the benefits of B-alanine supplementation.
Vince Kelly also offers tailored Ultra Running coaching and training through Ultrarun Coach.