Amino acids are the building blocks for protein. Therefore, they are proteins that have been broken down or pre-digested, where the body can immediately use them. The amino acid leucine is the key trigger for protein synthesis and this can be achieved with a dose of 2-3 grams. Whey protein is a rich source of leucine and maximal protein synthesis can be achieved with a whey protein serving of ~20- 25g. It is popular for supplement companies to add additional amino acids to whey protein powders. This increases the cost of the supplement but is unlikely to have any additional benefits to the consumer.