4.lapa
Zigurds Zariņš: "There is reason to suspect that protein-containing 'power drinks' may contain stimulants. In Latvia, it is not possible to analyze these 'power drinks' for the presence of stimulants not listed in the beverage description. It is very likely that the 'surge of strength' sometimes observed is not from amino acids but is due to stimulants." ("Uztura mācība", p. 95)