Table 1.

Age and gender thresholds for study inclusion

	Male	Female
Range of knee joint flexion
55-64 years	< 128°	< 127°
65-74 years	< 125°	< 122°
75+ years	< 120°	< 117°
Isometric quadriceps strength (kilograms force)
55-64 years	< 18.1	< 11.3
65-74 years	< 17.2	< 9.4
75+ years	< 13.9	< 9.0
Single-leg standing balance (seconds)
55-64 years	< 8	< 5
65-74 years	< 3	< 3
75+ years	< 2	< 2