Background: Maximal and rapid strength characteristics of the knee extensor and fl exor muscles play an important role in fall prevention and walking-related performances; however, few studies have investigated the ability of these variables to identify chair-rise performances in very old adults. Purpose: To examine the effectiveness of maximal and rapid isometric strength characteristics of the knee extensors and fl exors to differentiate between very old adults who are able (higher functioning) versus unable (lower functioning) to independently rise from a chair. Methods: Nine higher functioning (age, 87 ± 6 years) and 6 lower functioning (age, 89 ± 6 years) very old adults performed 2 isometric maximal voluntary contractions of the knee extensors and fl exors. Peak moment and absolute and relative rate of moment development (RMD) at the early (0-50 ms) and late (0-200 ms) phases of muscle contraction were examined during each maximal voluntary contraction. Results: Absolute and relative RMD values at 0 to 50 ms were greater ( P = .02 and .03, respectively) in the higher functioning than in the lower functioning individuals for both the knee extensors and fl exors. However, no group-related differences ( P = .39-.58) were observed in either muscle group for peak moment or absolute and relative RMD at 0 to 200 ms. Conclusions: Early rapid moment production of the knee extensors and fl exors may be an effective measure for discriminating between very old adults of different chair-rise performance abilities. Physical therapists and other practitioners may use these fi ndings to help with the identifi cation and early detection of older adults who are at a high risk for functional decline.
- Functional decline
- Isometric testing