The authors from Madrid, Spain, recruited 27 subjects to receive either 4 grams a day of beta-alanine powder or placebo over the four-week study period to assess effects on neuromuscular fatigue in individuals engaging in HIFT and subsequent sports performance.
Results showed that beta-alanine supplementation improves measures of vertical jump and power, leading the researchers to conclude that a "four-week beta-alanine intake program demonstrated an improvement in the capacity of subjects."
Neuromuscular fatigue
Beta-alanine, a non-essential amino acid found in the diet and produced through nucleotide catabolism, is significant for muscle performance due to its role in carnosine synthesis.
Carnosine is abundant in skeletal muscle and acts as a buffer, antioxidant and ATPase activator. Fast twitch muscle fibers contain more carnosine than slow twitch fibers, benefiting athletes in high-intensity sports, and β-Alanine supplementation has been shown to boost muscle carnosine levels, enhancing performance and delaying fatigue.
HIFT combines various exercises to improve strength, endurance and overall fitness. It primarily relies on phosphocreatine for ATP resynthesis, however, phosphocreatine reserves are typically depleted within 10 to 30 seconds of HIFT, resulting in neuromuscular fatigue.
Study details
All study participants possessed over 18 months of experience in resistance training and participated in HIFT on the first day to induce fatigue and work close to their VO2 max. After four weeks of supplementation or placebo, they repeated the exercise experiment.
The researchers measured blood samples before and after workouts, assessed muscular fatigue through validated tests and asked participants to rate their level of exertion following workouts.
Results showed that only participants in the supplemented group experienced statistically significant changes in the sports performance variables, specifically vertical jump and jumping power. No alterations were observed in any other variables, including fatigue, metabolic intensity of exercise or perceived intensity.
The researchers suggested that the improvement may be related to the antioxidant effects of beta-alanine supplementation, its involvement in the protection of glycation and its relationship with the generation of carnosine.
“These effects serve to buffer the drop in pH generated by the accumulation of metabolic waste, which may increase muscle performance,” they wrote.
The study noted that future research should extend the supplementation period to understand whether this would result in a more pronounced statistical difference between the study groups.
“It would be beneficial to examine the impact of varying the dose administered to the subjects in the experimental group while ensuring that the dosage does not exceed a level that could potentially lead to adverse effects,” they added.
Journal: Nutrients
“Effects of β-Alanine Supplementation on Subjects Performing High-Intensity Functional Training.”
doi: 10.3390/nu16142340
Authors: Cimadevilla-Fernández-Pola, E. et al.