Clinical Trial Details
— Status: Recruiting
Administrative data
| NCT number |
NCT05827666 |
| Other study ID # |
43728 |
| Secondary ID |
|
| Status |
Recruiting |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
February 1, 2023 |
| Est. completion date |
December 2023 |
Study information
| Verified date |
April 2023 |
| Source |
University of Toronto |
| Contact |
Daniel R Moore, PhD |
| Phone |
4169464088 |
| Email |
dr.moore[@]utoronto.ca |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
The growth and development of lean body mass (i.e., muscle and bone) is instrumental to
health and performance across the lifespan, especially in youth, as they actively experience
growth. Thus, it is important to capitalize on physical activity and nutrition (especially
dietary protein), to support the accretion of lean tissues. Eating a protein-rich meal or
performing physical activity can stimulate protein synthesis, and when repeated over time,
lean body mass accretion. There is currently an increasing market demand for non-dairy
alternatives, due to multiple reasons including environmental, ethical, or taste preferences.
However, it is important to understand how different beverages may support 'growth'
(anabolism) of lean tissues after exercise. Research in adults has shown that dairy milk is
superior to non-dairy milk beverages for supporting post-exercise recovery and muscle protein
synthesis. However, the impact of dairy and non-dairy milk alternatives on recovery from
exercise is not well understood in children. By understanding the milk beverage that best
supports post-exercise recovery, the investigators can determine the optimal nutritional
environment to facilitate the growth of lean tissues in the body.
Description:
The growth and development of lean body mass (LBM) (e.g., muscle and bone) is vital to not
only support health and performance across the lifespan but also, reduce the prevalence of
metabolic disorders later in life, such as osteoporosis and sarcopenia. Active youth who
regularly perform moderate-to-vigorous physical activity (MVPA) have superior increases LBM
and muscle strength compared to their sedentary counterparts. LBM is regulated by the process
of protein breakdown (PB), where old or damaged proteins are broken down releasing their
constituent amino acids (AA), as well as protein synthesis (PS), a process by which new
proteins are made by linking constituent AAs together. When rates of PS exceed rates of PB
(PS>PB), a positive net protein balance is achieved, ultimately facilitating the accretion of
LBM. Contrarily, if PB>PS, net protein balance is negative, leading to the loss of LBM.
Assuming total energy intakes are met, to meet the metabolic demands of an active lifestyle,
dietary protein is a prime anabolic stimulus. This macronutrient facilitates the growth of
lean tissues by providing the AA 'building blocks' to support the synthesis of muscle and
other body proteins. Physical activity (PA) is a second pre-eminent factor contributing to
the growth of LBM. Following exercise, in the absence of dietary protein ingestion, net
protein balance is negative. However, post-exercise protein consumption facilitates a
positive net protein balance, which when repeated over time, can contribute to the accretion
of LBM. Youth who engage in high levels of PA have greater LBM compared to their sedentary
counterparts. Thus, it is important to capitalize on the optimal nutritional and exercise
interventions to support a positive net protein balance, an acute marker of growth,
especially in vulnerable populations, such as children.
In children, milk protein ingestion has been shown to stimulate whole-body PS, resulting in a
positive whole-body net protein balance. In adults, dairy proteins lead to superior
post-exercise recovery and PS compared to non-dairy alternatives. Most research to date
examining the post-prandial protein synthesis responses to plant-based protein sources have
encompassed isolated protein sources. However, there is currently a paucity of research
examining the effect of the whole-food matrix of plant-based protein sources on whole-body
protein metabolism in active youth. Furthermore, the pubertal growth spurt is characterized
by rapid accumulation of LBM that is only surpassed by the first year of life. This LBM,
which is enhanced by an active lifestyle, must be supported by adequate energy and protein
ingestion. Therefore, it is necessary to determine the post-exercise anabolic effect of dairy
and non-dairy whole foods on markers of LBM growth and whole-body protein metabolism,
especially in children, an under-researched population.
The current project will employ the indicator amino acid oxidation (IAAO) methodology to
determine the protein/AA intake that minimizes oxidation of the indicator AA, while
maximizing PS. The oxidation of the indicator AA is minimized by ingesting an adequate
proportion of AA, and/or consuming nutritionally complete protein sources. The main objective
of the present study is to determine the effect of energy-matched dairy and non-dairy milk
alternatives on whole-body protein synthesis in active youth following exercise.
Aim 1: To determine the effect of dairy (2% milk) and non-dairy milk alternatives (soy, rice,
and almond 'milk' beverages) on whole-body PS following a bout of intermittent exercise in
children, adolescent males, and adolescent females.
Hypothesis 1: Whole body PS will be greatest after ingestion of dairy milk compared to
isocaloric (i.e., equal energy amount) non-dairy alternatives, due to the greater and/or
higher amount of quality dietary protein. Regardless of sex, adolescents are expected to have
greater PS due to their heightened anabolic sensitivity, compared to children.
