When discussing the evidence for BCAAs, the possible dual effect of BCAAs has to be taken into consideration. The positive effects on prolonged time to fatigue are relatively well substantiated. It should also be noted that not all studies that found a positive effect on the time to exhaustion, investigated only BCAA. Two studies added arginine and citrulline to the BCAA supplementation (Chen et al., 2016; Hsueh et al., 2018) and one study added carbohydrates and alanine (Gervasi et al., 2020). Therefore, synergistic effects cannot be excluded (click: see how the ingredients work together), but positive results were also found when only BCAA was supplied to the participants (AbuMoh’d, 2020; Chang et al., 2015; Kim et al., 2013 and Moberg et al., 2016). Another factor is that the studies mainly focus on males. Accordingly, it is very likely that BCAA enhances sport performance by postponing exhaustion. The used dose varies between 3.2 g up to 0.17 g/kg BW (which is 11.9g for a person of 80 kg). To the best of our knowledge, no research has been performed on the most functional dose, therefore the optimal dose is suggested to be in this range, which gave positive effects on the time to exhaustion. Although, the best dose can be outside this range.
Evidence for the effect of BCAA on muscular level is quite poor. In the articles reviewed, no causality was found for the supplementation of BCAA alone on the reduction on muscle damage or muscle strength and mass. The potential benefits for low up to moderate muscle damage, only occur when the athlete had daily a high intake of BCAAs for a long period of time before muscle damage occurred. This is not the scope of Energy Water. Besides, no direct evidence is available suggesting that the intake of BCAAs really helps in diminishing the effects of muscle damage. The International Society of Sports Nutrition (ISSN) also categorizes the evidence for BCAA efficiency as not strong, but as mixed (Kerksick et al., 2018). However, leucine is a very important amino acid in muscle development. Therefore, more specific literature research on the effect of L-leucine on enhancing muscle strength and mass should be carried out.
The evidence for a positive effect on sport performance for all different kind of athletes is quite strong. This has only to do with the reduction of central fatigue, in order for the athlete to remain longer focus and make better decisions. The evidence for the effect on the muscular level of specifically BCAA alone is quite poor. On muscular level a complete protein source is recommended.