Clinical Trial Details
— Status: Active, not recruiting
Administrative data
NCT number |
NCT04347447 |
Other study ID # |
IRB-2019-218 |
Secondary ID |
|
Status |
Active, not recruiting |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
May 1, 2020 |
Est. completion date |
December 1, 2024 |
Study information
Verified date |
August 2023 |
Source |
Purdue University |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Loss of muscle mass and strength is a well-established outcome of normal aging. Muscle
strength and mobility are also dependent on the quality and strength of connective tissue,
which surrounds skeletal muscle. These layers, which are continuous with tendons, allow for
the effective transfer of tension from skeletal muscle to bone to enable movement.
Importantly, skeletal muscle strength is directly related to connective tissue strength.
Greater tendon connective tissue cross-sectional area and stiffness optimize force transfer
through tendon to maximize musculoskeletal function. As with skeletal muscle, tendon
connective tissue quality declines with age. Previous research indicates that resistance
training can improve muscle strength in older adults, but may not counter the effects of
aging on tendon. The specific problem is that no approaches are available that benefit both
skeletal muscle and tendon health to minimize loss of muscle mass and quality while also
improving connective tissue quality and function in older adults. A critical need exists to
assess approaches that improve both muscle and connective tissue strength and function. This
need is highly relevant for older women, due to their higher risk of sarcopenia than men.
Resistance training, especially when combined with higher protein intake, has been
consistently shown to improve muscle mass and strength in older adults. Further, emerging
research indicates that diets rich in total and indispensable amino acids (as in beef)
augment exercise-induced improvements in tendon cross-sectional area in rodents and young
humans. However, limited research exists on the impact of beef consumption combined with
resistance training on muscle and tendon tissue outcomes, especially in older women. This
research study will assess the effects of consuming a healthy, protein-rich diet emphasizing
lean beef, compared to a healthy, normal-protein, lower beef diet (control 1), and a healthy
protein-rich, lower beef diet emphasizing non-beef/red meat protein (control 2) on resistance
training-induced changes in muscle and tendon tissue size, strength, and quality in older
women.
Description:
Sarcopenia, i.e., loss of muscle mass and strength, is a well-established consequence of
normal aging. Skeletal muscle strength and mobility is also dependent on the composition and
mechanical properties of connective tissue, which encase skeletal muscle allowing for
effective transfer of tension developed during cross-bridge cycling. Importantly, skeletal
muscle strength and function is directly related to connective tissue strength. Specifically,
greater tendon connective tissue cross-sectional area (CSA) and stiffness optimize force
transfer through tendon to maximize musculoskeletal function, including muscle power output,
locomotion economy, and control of balance. As with skeletal muscle, aging leads to the
decline of tendon connective tissue quality, including reductions in tendon collagen (the
primary structural component of tendon), and a decrease in tendon CSA. Previous research
indicates that resistance training (RT) can improve muscle mass and strength in older adults
but may not counter the effects of aging on tendon. Specifically, a 12-week RT protocol
improved tendon properties in young but not older adults. The specific problem is that no
approaches are available that target both skeletal muscle and tendon health to minimize loss
of muscle mass and quality while simultaneously improving connective tissue quality and
function in older adults. Therefore, a critical need exists to scientifically assess
interventions that concomitantly improve muscle and connective tissue strength and function.
This need is highly relevant for older women, due to their higher risk of sarcopenia than
men.
Resistance training, especially when combined with higher protein intake, has been
consistently shown to improve muscle mass and strength in older adults. However, limited
research exists on the impact of beef consumption combined with RT on sarcopenia-related
outcomes, especially in older women. Further, emerging research indicates that diets rich in
leucine or glycine (as in beef) augment resistance or aerobic exercise-induced improvements
in tendon CSA in rodents and young humans. However, the potential benefit of lean proteins,
such as beef, on connective tissue adaptations in older adults requires investigation. This
study will assess the effects of consuming a healthy, protein-rich diet emphasizing lean beef
on RT-induced changes in skeletal muscle and tendon connective tissue size, strength, and
quality in older women. It is hypothesized that consumption of a healthy diet high in protein
from predominately lean beef will augment improvements in both skeletal muscle and tendon
responses to RT, when compared to consuming a healthy diet with normal or high-protein and
less total red meat. The overall healthy diet will be modeled from the U.S. Healthy Eating
Pattern and consistent with the 2015-2020 Dietary Guidelines for Americans.