Distinguishing four components underlying physical activity: a new approach to using physical activity questionnaire data in old age

Table 3 Spearman correlations coefficient between measured muscle strength and the four physical activity component scores in the sub sample.

	Measured quadriceps strength	Measured handgrip strength
Muscle strength component	.36	.37
Intensity component	.33	.32
Mechanical strain component	.02	.00
Turning actions component	-.15	-.29

ISSN: 1471-2318