Writing in the journal Nutrients, researchers from Beijing Sport University and Beijing Sports Nutrition Engineering Research Center compared the effects of the BCAA-enhanced sports drink to a standard carbohydrate–electrolyte sports beverage or water in athletes participating in a 21-km run.
BCAA-enhanced sports drinks
Sports drinks typically contain carbohydrates and electrolytes and are popular among athletes looking to replenish lost fluids and maintain fluid balance. These commonly include sodium, potassium and chloride, all of which have been found to support cell function and prevent muscle cramps.
Recently, some sports drinks have added BCAAs to enhance fluid replacement and reduce muscle damage; however, their effectiveness in sports drink formulation is not fully confirmed. BCAAs, especially leucine, can also affect the flavor and solubility of the drink, limiting their dosage.
Study details
The study recruited 14 trained male participants who completed four randomized 21-km running trials, in which they were instructed to consume either a BCAA-containing electrolyte beverage (AE), a standard carbohydrate-electrolyte beverage (CE), water (W) or no hydration at 5 km, 10 km and 15 km.
Body mass and muscle strength were assessed, and blood samples were collected before and after exercise. Perceptual scales were administered during and after running. Blood electrolyte levels (sodium, potassium and chloride) and creatine kinase (CK) concentration were also analyzed.
Results showed that the participants in the rehydration groups lost less body weight post-exercise compared to the no-rehydration group.
AE had the best effect on plasma volume. The researchers suggested that fluid supplementation helps maintain plasma volume, but the amount of fluid consumed was insufficient to fully counteract losses during exercise.
No significant differences in performance were found across the four hydration strategies. Despite some dehydration, participants still performed similarly, aligning with studies that suggest moderate dehydration does not significantly impair endurance.
The researchers concluded that AE may help with muscle recovery, as serum creatine kinase (CK) levels and muscle soreness were lower in the AE group compared to others. BCAAs in AE likely activated the mTOR pathway, which aids in muscle repair, although the optimal dosage of BCAAs for recovery remains uncertain.
Electrolyte balance showed that AE was most effective for potassium (K+) maintenance, likely due to its higher K+ content. There were no significant differences in sodium (Na+) or chloride (Cl-) balance, as Na+ loss was greater than intake during exercise.
According to the researchers, the increase in serum Na+ levels after exercise suggested dehydration, highlighting the importance of electrolyte beverages for proper fluid replenishment.
They noted that future research should examine BCAAs in real-world settings and across diverse populations to be able to improve recommendations for hydration and recovery strategies in athletes.
Source: Nutrients 2024, 16(22), 3799
doi: 10.3390/nu16223799
"Consumption of a Branched-Chain Amino Acids-Containing Sports Beverage During 21 km of Running Reduces Dehydration, Lowers Muscle Damage, and Prevents a Decline in Lower Limb Strength."
Authors: Liang, Z. et al.