The effect of a needle biopsy of the vastus lateralis on isokinetic muscular performance.
OBJECTIVE
To determine the acute effects of a needle muscle biopsy of the vastus lateralis on knee extension and flexion strength and endurance.


METHODS
Pretest-posttest design. Testing order of right or left leg was randomly determined.


METHODS
Research Laboratory, University of Alberta, Edmonton Alberta, Canada.


METHODS
The subjects were 8 female and 11 male volunteers who were recreationally active. The mean age, height, and weight were 23 +/- 5 years, 174.6 +/- 9.2 cm, and 73.5 +/- 7.3 kg, respectively.


METHODS
Isokinetic testing for knee extension and flexion was performed on both legs before and after a biopsy of the right vastus lateralis muscle.


METHODS
Knee extension and flexion peak torque measured at an angular velocity of 1.05 rad.s-1. Mean torque during 25 consecutive maximal contractions at 3.14 rad.s-1 for knee extension and flexion exercise.


RESULTS
There was a significant decrease in right knee extension peak torque after the biopsy of the vastus lateralis muscle. No other differences were noted.


CONCLUSIONS
These findings demonstrated an acute inhibition of knee extension peak torque but not endurance because of a muscle biopsy of the involved musculature.
Department of Physical Therapy, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
J
J
Laskin
G
G
Bell
R
R
Burnham
D000328:Adult; D001707:Biopsy, Needle; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D007866:Leg; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular