View Full Version : Normative isometric knee ext force data vs joint angle

11-05-2007, 07:32 PM
Dear subscribers

I wonder whether anyone knows about normative data on isometric knee
extension forces (or torques) at various knee joint angles. An
interesting source for isometric normative data is

authors = {A W Andrews and M W Thomas and R W Bohannon},
title = {Normative values for isometric muscle force measurements obtained
with hand-held dynamometers},
journal = {Physical Therapy},
year = 1996,
volume = 76,
pages = {248-259}

but the knee extension is only for 90 degree joint angle (180 degree =
straight leg). Since we have data [elderly participants] for 120 degree
joint angle we would like to compare with normative data at this angle.
From some textbook examples about force-length relations my guess
[which is no substitute for real data ...] is that MVC leg extension
torque is about 20 % higher on the average for 120 degree joint angle
compared to 90 degree joint angle . (For 120 joint angle one has also to
take into account the gravity which for an adult may correspond to a
torque > 5 Nm.) Pointers to some accessible isometric normative data
for a wider range of angles would be appreciated.

Best Regards
Frank Borg

U of Jyväskylä, Chydenius Institute, Karleby, Finland