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In vivo Measurement of Knee Extensor Muscle Function in Mice
Published on: March 4, 2021
Functional and morphological adaptations to aging in knee extensor muscles of physically active men
Bruno Manfredini Baroni1, Jeam Marcel Geremia, Rodrigo Rodrigues
1Exercise Research Laboratory, Physical Education School, Federal University of Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Journal of Applied Biomechanics
|November 28, 2012
Summary
A physically active lifestyle alone, without systematic training, does not prevent age-related muscle and strength loss. Elderly men showed significant declines in muscle function and mass compared to younger adults.
Area of Science:
- Gerontology
- Exercise Physiology
- Muscle Biology
Background:
- Age-related muscle loss (sarcopenia) and strength decline are significant health concerns.
- The role of a generally physically active lifestyle versus systematic training in mitigating these changes is unclear.
Purpose of the Study:
- To determine if maintaining a physically active lifestyle, without structured training, is sufficient to prevent age-related muscle impairments.
- To compare functional and morphological muscle properties across different age groups of healthy men.
Main Methods:
- Evaluated 33 healthy men across three age groups: young (30±6y), middle-aged (50±7y), and elderly (69±5y).
- Assessed knee extensor muscle function (isometric and concentric peak torques) and morphology (vastus lateralis architecture).
- All participants maintained similar physical activity levels (International Physical Activity Questionnaire score = 2).
Main Results:
- Elderly men exhibited 30-36% lower isometric peak torques and 40-53% lower concentric peak torques compared to young adults.
- Middle-aged men showed 18-32% lower concentric peak torques than young adults.
- Vastus lateralis muscle thickness and fascicle length were significantly reduced in the elderly group compared to the young group.
Conclusions:
- A physically active lifestyle, in the absence of systematic training, is insufficient to fully counteract age-related decreases in muscle strength and mass.
- Systematic training may be necessary to preserve muscle function and morphology throughout aging.
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