Protein Clinic also contains a blend of non-GMO pea protein isolate and rice protein isolate to support lean muscle mass (and a happy stomach). Although whey is considered the gold standard of protein supplementation, pea protein yields similar strength and muscle adaptations when taken in conjunction with resistance training.<sup>27</sup> Pea protein lacks the amino acid methionine.<sup>28</sup> However, you can easily remedy this by combining it with rice protein, which has a healthy dose of methionine. These two plant-based proteins provide optimal amounts of all nine essential amino acids. Pea protein is high in the amino acid leucine. This helps explain its superior muscle-building power versus other plant proteins like hemp, soy, and chickpea.