Protein requirements in active individuals have been suggested to be greater than the current recommended dietary allowance (RDA).

Nutritional requirements for dietary amino acids in adolescents have traditionally been determined utilizing the nitrogen balance technique, which is prone to underestimating protein requirements. As a result, there is a need to re-evaluate recommendations in order to characterize how dietary amino acid needs may be modulated by physical activity.

Recent studies using the minimally invasive indicator amino acid oxidation (IAAO) technique have suggested that protein requirements in young men are at least 50% higher than the RDA based on nitrogen balance data.

The purpose of this study is to measure the protein requirement in adolescent, females using the IAAO technique in the presence of a variable intensity exercise stimulus.

Inclusion Criteria (Adolescents):

• Healthy, active adolescent who regularly participates in moderate to vigorous physical activity 5 times a week for a minimum of 1 hour.
• Being -0.5 to +1.0 years from peak height velocity, determined by the ratio of standing to sitting height, with the maximal age for adolescents being 16 years.

Obtaining a minimum level of 5.8 on the Beep Test

Exclusion Criteria (All Subjects):

• Inability to meet health and physical activity guidelines according to the Physical Activity Readiness Questionnaire (PAR-Q+) and Physical Activity Questionnaire,
• An inability to adhere to any of the protocol guidelines (i.e. caffeine consumption)
• A biological age falling outside of the aforementioned ranges