Source: Medicine & Science in Sports & Exercise
Summary:
Leg extensor power was measured in 101 pairs of monozygotic and 116 dizygotic female twin age 63-76
Leg extensor power and isometric knee extensor strength shared a genetic component
The two traits are regulated by the same genes but environmental effects also contribute
Conclusion: Although half of the muscle power and isometric strength were due to genetics, the other half was determined by environmental factors, such as physical activity
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