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Sex differences in the relationship between strength, endurance and limb morphology
Journal of Human Ergology
|December 1, 1978
Summary
This study explored leg density measurement methods and the impact of physical activity on leg composition. Findings indicate leg density influences the center of mass and exercise training alters leg strength and girth.
Area of Science:
- Biomechanics
- Exercise Physiology
- Anthropometry
Background:
- Accurate measurement of leg density is crucial for understanding body composition.
- Previous research has not fully elucidated the relationship between physical activity and leg composition changes.
Purpose of the Study:
- To investigate reliable methods for measuring leg density.
- To determine the effects of a structured training program on leg density, size, and strength.
- To compare changes between genders and across different exercise levels.
Main Methods:
- Determined leg center of mass and weight in 65 female college students using single and double scale methods.
- Assessed changes in leg density, girth, and strength in 14 participants (7 males, 7 females) over a five-week strength training period.
Main Results:
- The leg's center of mass was found to be 43% distal from the trochanter, correlating positively with leg density.
- Strength training led to increased strength in both males and females, with females also showing reduced girth.
- Habituation to exercise and faster strength adaptation compared to size/weight changes were observed.
Conclusions:
- Leg density is a significant factor in determining the center of mass.
- Physical activity, specifically strength training, demonstrably alters leg composition, impacting strength and girth.
- Individual responses to exercise, including gender differences and habituation, influence adaptation rates.
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