Effect of β-alanine supplementation during high-intensity interval training on repeated sprint ability performance and neuromuscular fatigue

Abstract

The study investigated the influence of β-alanine supplementation during a high-intensity interval training (HIIT) program on repeated sprint ability (RSA) performance. This study was randomized, double-blinded, and placebo controlled. Eighteen men performed an incremental running test until exhaustion (TINC) at baseline and followed by 4-wk HIIT (10 × 1-min runs 90% maximal TINC velocity [1-min recovery]). Then, participants were randomized into two groups and performed a 6-wk HIIT associated with supplementation of 6.4 g/day of β-alanine (Gβ) or dextrose (placebo group; GP). Pre- and post-6-wk HIIT + supplementation, participants performed the following tests: 1) TINC; 2) supramaximal running test; and 3) 2 × 6 × 35-m sprints (RSA). Before and immediately after RSA, neuromuscular function was assessed by vertical jumps, maximal isometric voluntary contractions of knee extension, and neuromuscular electrical stimulations. Muscle biopsies were performed to determine muscle carnosine content, muscle buffering capacity in vitro (βmin vitro), and content of phosphofructokinase (PFK), monocarboxylate transporter 4 (MCT4), and hypoxia-inducible factor-1α (HIF-1α). Both groups showed a significant time effect for maximal oxygen uptake (Gβ: 6.2 ± 3.6% and GP: 6.5 ± 4.2%; P > 0.01); only Gβ showed a time effect for total (−3.0 ± 2.0%; P = 0.001) and best (−3.3 ± 3.0%; P = 0.03) RSA times. A group-by-time interaction was shown after HIIT + Supplementation for muscle carnosine (Gβ: 34.4 ± 2.3 mmol·kg−1·dm−1 and GP: 20.7 ± 3.0 mmol·kg−1·dm−1; P = 0.003) and neuromuscular voluntary activation after RSA (Gβ: 87.2 ± 3.3% and GP: 78.9 ± 12.4%; P = 0.02). No time effect or group-by-time interaction was shown for supramaximal running test performance, βm, and content of PFK, MCT4, and HIF-1α. In summary, β-alanine supplementation during HIIT increased muscle carnosine and attenuated neuromuscular fatigue, which may contribute to an enhancement of RSA performance. NEW & NOTEWORTHY β-Alanine supplementation during a high-intensity interval training program increased repeated sprint performance. The improvement of muscle carnosine content induced by β-alanine supplementation may have contributed to an attenuation of central fatigue during repeated sprint. Overall, β-alanine supplementation may be a useful dietary intervention to prevent fatigue.

Effects of self-paced high-intensity interval training and moderateintensity continuous training on the physical performance and psychophysiological responses in recreationally active young adults

“…In accordance with the improvement in V̇O 2max results, we found a considerable increase in RSA performance of 9.2% after the 8-week self-paced HIIT intervention. In another study, supporting findings were observed for the RSA that, a 6-week HIIT training intervention induced a decrease by 1.5% their total time of RSA [ 41 ]. In another study, Cicioni-Kolsky et al [ 42 ] showed that the RSA test duration decreased from 36.0 ± 1.9 ml·min -1 ·kg -1 to 35.0 ± 1.3 ml·min -1 ·kg -1 with an increase of 3.7% after 6-week HIIT in recreationally and moderately trained young males.…”

One-Week High-Dose β-Alanine Loading Improves World Tour Cyclists’ Time-Trial Performance

“…Increased H + production is partly buffered inside the muscle by carnosine ionic microdomains, which deposits H + /Ca 2+ in the cytoplasm to regulate intracellular pH, partly expelling the remaining H + to systemic blood [ 3 ]. Previous studies with trained cyclists performing time-trials [ 25 , 27 , 33 ] or after 1-h of moderate intensity cycling [ 34 ] did not observe a difference in lactate or blood pH by β-ala. On the other hand, athletes engaged in high-intensity interval training yielded higher lactate values compared to placebo after these efforts [ 35 , 36 ] in line with our results. However, the buffering capacity of muscles did not change in these studies in spite of an increased muscle carnosine, suggesting an improved muscle force in short-duration high-intensity movements by acting on neuromuscular fatigue.…”

Drop jumps versus sled towing and their effects on repeated sprint ability in young basketball players

“…Participants performed two 5 s maximal voluntary contractions (MVCs) with the knee extensors of their self-reported dominant leg, interspersed with 1 min of passive rest [8,23,24]. The two MVCs were performed at baseline and as soon as possible after (77.50 ± 21.49 s) the RSA test.…”

“…The two MVCs were performed at baseline and as soon as possible after (77.50 ± 21.49 s) the RSA test. The measurements were carried out in a specific chair designed for maintaining hip and knee flexion at 90°, with participants secured by straps [8,23,24]. A metal rod was attached to the ankle and connected to a load cell with a maximum capacity of 100 kgf (MK Controle, São Paulo, SP, Brazil).…”

“…The optimal intensity of stimulations was determined individually before each session by the application of consecutive incremental doublets to the relaxed muscle (square-wave, 100 Hz, pulse duration of 1 ms, initial intensity of 80 mA with 20 mA increments) until a plateau in force was reached [8,24]. The maximal electrical current achieved (mA) was recorded, and supramaximal stimulation was ensured by increasing the final intensity by ~ 20% (253 ± 58 mA) [23,24]. Doublet, high-frequency stimulation (i.e., square-wave, 100 Hz, pulse duration of 1 ms) were delivered during MVCs (~ 2 s), followed doublets at high frequency (Db100; stimulation frequency in Hertz) 5 s after MVCs, a single stimulus was delivered at 10 s and finally a low frequency stimulation (Db10; stimulation frequency in Hertz) was delivered at 15 s after MVC, with the muscle in a relaxed state [25].…”