Table 2.

Empirical evidence of race differences in skeletal muscle properties.

Reference	Sample	Method to assess skeletal muscle properties	Results: African Americans Relative to Whites
			Fiber Type Proportion	Enzyme Activity
45	46 men Sedentary and matched for age, height, body weight, and body mass index	Muscle biopsy of vastus lateralis at rest	↓ type I ↑ type IIa = type IIb	↑ 30 to 40% phosphagenic and glycolytic metabolic pathways = oxidative enzymes
46	28 men	Muscle biopsy of vastus lateralis	= type I = type IIa = type IIb
47	18 men Untrained, healthy	31P-NMR spectroscopy in flexor carpi radialis muscle during exercise		↑ relative decrease in muscle pH ↑ inorganic phosphate/phosphocreatine ratio
49	53 women	Muscle biopsy of rectus abdominus at rest	↓ type I (obese) = type I (lean) ↑ type IIb (obese) = type IIb (lean)
72	12 men Runners	Muscle biopsy of vastus lateralis at rest	= type I	↑ 50–54% oxidative enzymes = phosphofructokinase activity

Note. ↓ indicates variable is lower (↑higher, = equivalent) in African Americans compared to Whites.