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Reliability and effects of leg dominance on lower extremity isokinetic force and work using the closed chain rider system

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Abstract and Figures

The purpose of our study was to assess the reliability of the Closed Chain Rider System between exercise sessions and to determine the effects of arm dominance using muscle force, work, and power measures during closed chain chest-press exercise. Sitting subjects underwent identical testing on 2 occasions and performed 5 reciprocal chest-press movements at speeds of 51 and 76 cm/s. Thirty-eight healthy college students. Average force, total work, average power, and linear range of motion were recorded. Reliability was evaluated by calculating intraclass correlation coefficients. Mean differences between the dominant and nondominant arms for the measured variables were analyzed by dependent t tests. For both the dominant and nondominant arms at the 51 and 76 cm/s speeds, reliabilities of average force (range = 0.85 to 0.91), total work (range = 0.88 to 0.92), and average power (range = 0.86 to 0.89) were clinically acceptable. The dominant arm produced significantly greater average force, total work, and average power compared with the nondominant arm. Our results provide clinically useful information about the reliability of force, work, and power measures during multijoint bilateral chest-press movement. Clinicians should be aware of measured differences between dominant and nondominant arms.
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Journal
of
Athletic
Training
1999;34(4):358-361
C
by
the
National
Athletic
Trainers'
Association,
Inc
www.nata.org/jat
Reliability
and
Effects
of
Arm
Dominance
on
Upper
Extremity
Isokinetic
Force,
Work,
and
Power
Using
the
Closed
Chain
Rider
System
John
E.
Kovaleski,
PhD,
ATC*;
Robert
J.
Heitman,
EdD*;
Larry
R.
Gurchiek,
DA,
ATC*;
Terry
L.
Trundle,
PTA,
ATCt
*
Health
and
Physical
Education
Department,
University
of
South
Alabama,
Mobile,
AL;
t
Progressive
Sports
Medicine,
Marietta,
GA
Objective:
The
purpose
of
our
study
was
to
assess
the
reliability
of
the
Closed
Chain
Rider
System
between
exercise
sessions
and
to
determine
the
effects
of
arm
dominance
using
muscle
force,
work,
and
power
measures
during
closed
chain
chest-press
exercise.
Design
and
Setting:
Sitting
subjects
underwent
identical
testing
on
2
occasions
and
performed
5
reciprocal
chest-press
movements
at
speeds
of
51
and
76
cm/s.
Subjects:
Thirty-eight
healthy
college
students.
Measurements:
Average
force,
total
work,
average
power,
and
linear
range
of
motion
were
recorded.
Reliability
was
evaluated
by
calculating
intraclass
correlation
coefficients.
Mean
differences
between
the
dominant
and
nondominant
arms
for
the
measured
variables
were
analyzed
by
dependent
t
tests.
Strength
training
is
considered
an
integral
part
of
upper
extremity
and
shoulder
rehabilitation.
A
popular
strength
training
method
is
closed
kinetic
chain
exercise,
which
involves
movement
when
the
distal
limb
segment
is
fixed,
body
weight
is
supported
by
the
extremity,
or
considerable
external
resistance
is
applied
to
the
foot
or
hand.'3
In
an
attempt
to
apply
the
closed
chain
concept
to
the
upper
extremity,
several
research-
ers
have
proposed
different
classification
systems
of
closed
kinetic
chain
exercise
to
define
and
develop
closed
chain
activities
for
upper
extremity
rehabilitation.3-6
For
example,
Dillman
et
a14
provided
a
classification
system
that
is
based
on
the
mechanics
of
the
particular
exercise
where
the
boundary
condition
of
the
distal
limb
segment
may
be
either
fixed
or
movable,
whereas
the
external
load
may
or
may
not
be
present
at
the
distal
segment.
For
the
purpose
of
rehabilitation,
closed
chain
strengthening
exercise
is
performed
to
promote
coactivation
of
stabilizing
muscles,
minimize
shear
forces,
stimulate
proprioceptors
in
the
involved
joints,
provide
large-resistance
and
low-acceleration
movements,
and
promote
dynamic
stabilization.3
The
need
exists
for
clinically
objective
and
reliable
measures
of
muscle
function
in
a
closed
kinetic
chain
movement
pattern.
The
Results:
For
both
the
dominant
and
nondominant
arms
at
the
51
and
76
cm/s
speeds,
reliabilities
of
average
force
(range
=
0.85
to
0.91),
total
work
(range
=
0.88
to
0.92),
and
average
power
(range
=
0.86
to
0.89)
were
clinically
acceptable.
The
dominant
arm
produced
significantly
greater
average
force,
total
work,
and
average
power
compared
with
the
nondominant
arm.
Conclusions:
Our
results
provide
clinically
useful
informa-
tion
about
the
reliability
of
force,
work,
and
power
measures
during
multijoint
bilateral
chest-press
movement.
Clinicians
should
be
aware
of
measured
differences
between
dominant
and
nondominant
arms.
Key
Words:
isokinetic
testing,
closed
kinetic
chain,
arm
strength
Closed
Chain
Rider
System
(Mettler
Electronics,
Anaheim,
CA)
is
an
integrated,
computer-controlled,
closed
chain
exercise
and
muscle
evaluation
system
that
provides
isokinetic
accommodating
resistance
with
distal
loading.
A
unique
aspect
of
this
system
is
the
linear
resistance
that
is
produced
during
alternating
multijoint
movements
at
various
velocities.
Reliability
using
intraclass
cor-
relation
coefficients
for
this
system
has
been
reported
employing
the
legs
for
average
force
(range
=
0.76
to
0.90)
and
total
work
(range
=
0.79
to
0.99).7
Measurements
were
reported
to
be
clinically
acceptable,
regardless
of
the
testing
speed
or
limb.
No
studies
have
established
the
reliability
of
measurement
for
the
upper
extremity
using
the
Closed
Chain
Rider
System.
The
purpose
of
our
study
was
to
establish
test-retest
reliability
using
bilateral
alternating
chest-press
movements
and
to
examine
the
effects
of
limb
dominance
using
muscle
force,
power,
and
work
parameters
during
a
closed
chain
chest-press
exercise.
METHODS
Subjects
Thirty-eight
(males
=
19,
females
=
19)
healthy
college
students
(age
=
22.3
±
2.9
years,
wt
=
72.7
±
17.7
kg,
ht
=
168.5
±
8.4
cm)
volunteered
to
participate.
Each
subject
358
Volume
34
*
Number
4
*
December
1999
Address
correspondence
to
John
E.
Kovaleski,
PhD,
ATC,
Health
and
Physical
Education
Department,
University
of
South
Alabama,
Mobile,
AL
36688.
E-mail
address:
jkovales@usamail.usouthal.edu
refrained
from
participating
in
heavy-resistance
weight
and
endurance
training
during
the
study,
although
the
usual
recre-
ational
and
daily
activities
were
allowed.
Subjects
refrained
from
vigorous
exercise
during
the
24
hours
before
testing.
In
compliance
with
institutional
guidelines,
the
study
was
ap-
proved
by
the
University
of
South
Alabama
Institutional
Review
Board,
and
subjects
read
and
signed
an
informed
consent
before
data
collection.
Instrumentation
Testing
of
the
right
and
left
upper
extremities
was
conducted
using
the
Closed
Chain
Rider
System.
The
Closed
Chain
Rider
System
consists
of
2
rail
extensions
that
contain
channels
for
the
movement
of
rubber-wheeled
rollers
attached
to
a
tubular
handle
(Figure).
When
engaged,
the
arm
couplers
are
con-
nected
by
a
chain-and-sprocket
system
to
a
motor
that
provides
the
braking
action
for
accommodating
resistance
during
exer-
cise.
Computer
software
controls
the
braking
action
of
the
system.
The
seat
back
was
reclined
to
approximately
1000
during
testing.
Subjects
were
secured
in
the
seat
by
a
pelvic
strap
for
pelvic
immobilization,
along
with
chest
straps
placed
over
the
shoulder
and
across
the
chest
to
stabilize
the
torso.
The
feet
were
placed
into
foot
pads,
secured,
and
locked
into
place
with
the
knees
positioned
at
a
900
flexion
angle
so
that
no
movement
of
the
lower
extremity
occurred
during
testing.
During
each
testing
session,
the
subjects
grasped
the
tubular
handles
attached
to
both
sides
of
the
rail
extensions
approxi-
mately
5
cm
from
the
top
of
the
handle.
Subjects
performed
an
alternating
unilateral
pushing
motion
consisting
of
shoulder
flexion
and
elbow
extension,
followed
by
the
reciprocal
motion
of
the
contralateral
extremity.
Subject
positioning
and
testing
was
performed
as
described
in
the
Closed
Chain
Rider
System
instruction
manual.8
Closed
Chain
Rider
System.
Protocol
Subjects
participated
in
1
pretest
and
2
test
sessions,
each
separated
by
5
to
7
days.
The
pretest
session
was
used
to
introduce
the
Closed
Chain
Rider
to
the
subjects,
provide
practice
exercise,
measure
body
weight
and
height,
and
deter-
mine
arm
dominance.
Subjects
were
asked
whether
they
were
right
or
left
handed
in
order
to
establish
arm
dominance.
The
subjects
then
performed
2
sets
of
10-repetition
reciprocating
chest-press
movements
(shoulder
flexion,
elbow
extension)
at
each
testing
speed
to
become
familiar
with
the
apparatus.
The
2
testing
sessions
were
identical
for
all
subjects.
Before
testing,
a
3-minute
warm-up
on
a
hand-crank
ergometer
was
performed.
A
total
of
3
to
5
submaximal
chest-press
repetitions
preceded
testing
at
each
of
the
2
speeds.
During
each
test
session,
5
repetitions
of
alternating
maximal
chest-press
move-
ments
at
speeds
of
51
and
76
cm/s
(20
and
30
in/s)
were
performed.
Subjects
were
instructed
to
perform
each
chest-
press
movement
as
fast
and
as
hard
as
possible
after
hearing
the
word
"go."
A
1-minute
rest
period
separated
testing
at
each
speed.
The
order
of
testing
during
the
2
days
was
randomly
assigned
and
balanced
using
2
different
progression
orders.
For
order
1,
the
51-cm/s
speed
was
tested
first,
and,
for
order
2,
the
76-cm/s
speed
was
tested
first.
Statistical
Analysis
Of
the
5
repetitions
performed
at
each
speed,
the
first
repetition
was
excluded
from
the
data
analysis
to
standardize
the
range
of
motion
so
that
work
values
could
be
calculated.8'9
Thus,
data
analysis
was
performed
using
the
mean
value
of
4
repetitions
in
the
statistical
analysis.
Test-retest
reliability
for
average
force
(kg),
total
work
(J),
and
average
power
(W)
was
evaluated
by
calculating
intraclass
correlations
(ICC
2,1).
10
An
ICC
value
of
0.75
or
greater
was
considered
high
and
clinically
acceptable.10
The
standard
error
of
measurement
(SEM)
was
calculated
as
a
measure
of
variability
expected
in
subjects'
scores.
A
dependent
t
test
was
conducted
to
test
the
null
hypothesis
of
no
difference
between
dominant
and
nondominant
limbs
for
average
force,
total
work,
and
average
power
on
day
1.
A
2-tailed
test
at
the
0.05
level
of
significance
was
used
for
all
tests.
Means
and
standard
deviations
(SDs)
were
used
to
describe
the
data.
RESULTS
The
mean
value
SD),
reliability
coefficients,
and
standard
errors
for
average
force,
total
work,
and
average
power
are
presented
in
Table
1.
The
reliabilities
of
average
force
(range
=
0.85
to
0.91),
total
work
(range
=
0.88
to
0.92),
and
average
power
(range
=
0.86
to
0.89)
measurements
were
clinically
acceptable
regardless
of
the
testing
speed
or
arm.'0
The
dominant
arm
produced
greater
(P
'
.05)
average
force,
total
work,
and
average
power
than
the
nondominant
arm
regardless
of
speed
(Table
2).
Average
linear
range
of
motion
Journal
of
Athletic
Training
359
Table
1.
Average
Force,
Total
Work,
and
Average
Power
for
Dominant
and
Nondominant
Arms
Variable
Day
1
(Mean
+
SD)
Day
2
(Mean
+
SD)
ICC
(2,1)*
SEMt
Speed
=
51
cm/s
Average
force
(kg)
Dominant
arm
11.79
±
4.4
11.42
±
4.2
0.89
1.43
Nondominant
arm
10.37
±
4.0
10.47
±
4.2
0.91
1.23
Total
work
(J)
Dominant
arm
192.32
±
84.9
184.58
+
81.4
0.92
23.52
Nondominant
arm
167.34
+
79.4
169.18
±
79.1
0.92
22.42
Average
power
(W)
Dominant
arm
44.11
±
19.3
42.84
±
17.6
0.88
6.39
Nondominant
arm
38.55
±
17.6
40.00
±
17.8
0.89
5.87
Speed
=
76
cm/s
Average
force
(kg)
Dominant
arm
9.71
±
4.4
9.37
+
3.8
0.88
1.42
Nondominant
arm
8.63
±
3.9
8.66
±
3.5
0.85
1.43
Total
work
(J)
Dominant
arm
173.92
±
86.7
162.24
±
79.9
0.90
26.34
Nondominant
arm
154.39
±
79.9
149.97
±
71.3
0.88
26.19
Average
power
(W)
Dominant
arm
44.97
±
23.8
41.63
±
21.4
0.86
8.46
Nondominant
arm
40.13
+
21.8
38.74
±
19.8
0.83
8.58
*Intraclass
correlation
coefficient.
tStandard
error
of
measurement.
Table
2.
t-Test
Comparisons
and
Percentage
Differences
Between
Dominant
and
Nondominant
Arms
for
Average
Force,
Total
Work,
Average
Power,
and
Range
of
Motion
for
Day
I
Dominant
Nondominant
Percentage
Variable
(Mean
±
SD)
(Mean
±
SD)
Difference
t
Value
P
Value
Speed
=
51
cm/s
Average
force
(kg)
11.79
±
4.4
10.37
±
4.0
12.0%
5.19
.001
Total
work
(J)
192.32
±
84.9
167.34
±
79.4
13.0%
5.78
.001
Average
power
(W)
44.11
±
19.3
38.55
±
17.6
12.6%
4.80
.001
Range
of
motion
(cm)
105.82
±
13.7
105.21
±
11.9
0.6%
1.07
.291
Speed
=
76
cm/s
Average
force
(kg)
9.71
±
4.4
8.63
±
3.9
11.1%
4.95
.001
Total
work
(J)
173.92
±
86.7
154.39
±
79.9
11.2%
5.27
.001
Average
power
(W\)
44.97
±
23.8
40.13
±
21.8
10.8%
4.20
.001
Range
of
motion
(cm)
113.89
±
15.0
114.50
+
15.5
0.5%
0.55
.583
was
not
significantly
different
between
the
dominant
and
joints
can
be
defined
as
a
kinetic
chain.3
Controversy
regarding
nondominant
arms
for
the
testing
speeds
(P
.
.05)
(Table
2).
the
use
of
the
term
"closed
kinetic
chain"
for
the
upper
extremity
is
mentioned
in
the
rehabilitation
literature.3"5
DISCUSSION
Weightbearing
forces
that
create
the
closed
kinetic
chain
effect
do
not
normally
occur
in
the
upper
extremity.
However,
If
closed
kinetic
chain
isokinetic
dynamometry
is
to
be
used
Steindler2
reported
that
the
kinetic
chain
concept
exists
in
the
for
muscle
performance
testing,
it
must
demonstrate
test-retest
human
when
the
hand
meets
considerable
resistance
versus
reliability.7
Several
published
reports
show
open
kinetic
when
it
is
free
to
move,
as
observed
in
the
open
kinetic
chain.
chain
isokinetic
assessment
of
upper
extremity
muscle
groups
Hand
placement
in
the
closed
chain
position
changes
neuro-
to
be
very
reliable,
with
reliability
coefficients
for
shoulder
muscular
activation
due
to
differences
in
proprioceptor
stimu-
internal-external
rotation
peak
torque
ranging
from
0.80
to
0.93
lation,
muscle
action,
and
joint
compressive
forces.
16-19
and
those
for
shoulder
flexion-extension
ranging
from
0.75
to
Clearly,
many
athletic
activities,
such
as
football,
wrestling,
0.95.12-14
The
reliability
coefficients
we
found
using
the
and
gymnastics,
require
the
upper
extremity
to
function
as
a
Closed
Chain
Rider
System
were
very
similar
to
those
reported
closed
kinetic
chain.
'5
using
isolated
open
kinetic
chain
motions,
despite
the
bilateral
The
12%
strength
differences
between
dominant
and
non-
alternating
multijoint
movement
that
occurred
during
the
dominant
arms
that
we
observed
make
closed
kinetic
chain
closed
kinetic
chain
exercise.
bilateral
comparisons
inappropriate
because
natural
differences
In
the
upper
extremity,
the
scapulothoracic
articulation
and
exist
between
extremities.
For
example,
Perrin
et
a120
reported
the
acromioclavicular,
sternoclavicular,
and
glenohumeral
that
dominant-side
muscle
group
strength
of
athletes
in
asym-
360
Volume
34
*
Number
4
*
December
1999
metric
upper
extremity
activities,
such
as
throwing,
may
be
up
to
15%
greater
than
the
strength
of
the
nondominant
side.
This
difference
in
muscle
performance
between
the
dominant
and
nondominant
limbs
may
affect
the
criteria
for
return
of
the
injured
extremity
to
a
normal
state
during
rehabilitation.
Additional
information
on
muscle
force,
work,
and
power
during
closed
kinetic
chain
isokinetic
exercise
is
needed
so
that
appropriate
rehabilitation
norms
can
be
established.
Future
studies
should
examine
the
efficacy
of
isokinetic
closed
chain
exercise
for
pathologies
involving
the
glenohumeral
and
scapu-
lothoracic
joints
and
should
substantiate
guidelines
for
use.
CONCLUSIONS
Regardless
of
testing
speed
or
arm
used
during
a
concentric
chest-press
exercise
pattern
with
the
Closed
Chain
Rider
System,
the
reliabilities
of
average
force,
total
work,
and
average
power
were
clinically
acceptable.
Clinicians
should
understand
that
natural
limb
differences
exist
between
domi-
nant
and
nondominant
arms
when
tested
in
a
closed
kinetic
chain.
REFERENCES
1.
Steindler
A.
Kinesiology
of
the
Human
Body.
Springfield,
IL:
Charles
C.
Thomas;
1955.
2.
Steindler
A.
Kinesiology
of
the
Human
Body
Under
Nornal
and
Patho-
logical
Conditions.
Springfield,
IL:
Charles
C.
Thomas;
1977.
3.
Lephart
SM,
Henry
TJ.
The
physiological
basis
for
open
and
closed
kinetic
chain
rehabilitation
for
the
upper
extremity.
J
Sport
Rehabil.
1996;5:71-
87.
4.
Dillman
CJ,
Murray
TA,
Hintermeister
RA.
Biomechanical
differences
of
open
and
closed
chain
exercises
with
respect
to
the
shoulder.
J
Sport
Rehabil.
1994;3:228-238.
5.
Gray
GW.
Chain
Reaction:
Successful
Strategies
for
Closed
Chain
Testing
and
Rehabilitation.
Adrain,
MI:
Wynn
Marketing;
1989.
6.
Panariello
RA.
The
closed
kinetic
chain
in
strength
training.
Natl
Strength
Cond
Assoc
J.
1991;
13:29
-33.
7.
Kovaleski
JE,
Heitman
RJ,
Gurchiek
LR,
Erdmann
JW,
Trundle
TL.
Reliability
and
effects
of
leg
dominance
on
lower
extremity
isokinetic
force
and
work
using
the
Closed
Chain
Rider
System.
J
Sport
Rehabil.
1997;6:319-326.
8.
Closed
Chain
Rider
Instruction
Manual.
Anaheim,
CA:
Mettler
Electron-
ics
Corp;
1995.
9.
Kovaleski
JE,
Heitman
RJ,
Scaffidi
FM,
Fondren FB.
Effects
of
isokinetic
velocity
spectrum
exercise
on
average
power
and
total
work.
J
Athl
Train.
1992;27:54-56.
10.
Shrout
PE,
Fleiss
JL.
Intraclass
correlation:
uses
in
assessing
rater
reliability.
Psychol
Bull.
1979;86:420-428.
11.
Davies
GJ,
Heiderscheit
BC.
Reliability
of
the
Lido
Linea
closed
kinetic
chain
isokinetic
dynamometer.
J
Orthop
Sports
Phys
Ther.
1997;25:133-
136.
12.
Hageman
PA,
Mason
DK,
Rydlund
KW,
Humpal
SA.
Effects
of
position
and
speed
on
eccentric
and
concentric
isokinetic
testing
of
the
shoulder
rotators.
J
Orthop
Sports
Phys
Ther.
1989;1
1:64-69.
13.
Hellwig
EV,
Perrin
DH.
A
comparison
of
two
positions
for
assessing
shoulder
rotator
peak
torque:
the
traditional
frontal
plane
versus
the
plane
of
the
scapula.
Isokinetic
Exerc
Sci.
1991;1:1-5.
14.
Perrin
DH.
Reliability
of
isokinetic
measures.
Athl
Train,
JNATA.
1986;
10:319-321.
15.
Wilk
KE,
Arrigo
CA,
Andrews
JR.
Closed
and
open
kinetic
chain
exercise
for
the
upper
extremity.
J
Sport
Rehabil.
1996;5:88-102.
16.
Borsa
PA,
Lephart
SM,
Kocher
MS,
Lephart
SP.
Functional
assessment
and
rehabilitation
of
shoulder
proprioception
for
glenohumeral
instability.
J
Sport
Rehabil.
1994;3:84-104.
17.
Bradley
JP,
Tibone
JE.
Electromyographic
analysis
of
muscle
action
about
the
shoulder.
Clin
Sports
Med.
1991;10:789-805.
18.
Davies
GJ,
Dickoff-Hoffman
S.
Neuromuscular
testing
and
rehabilitation
of
the
shoulder
complex.
J
Orthop
Sports
Phys
Ther.
1993;18:449-458.
19.
Moseley
JB,
Jobe
FW,
Pink
M,
Perry
J,
Tibone
J.
EMG
analysis
of
the
scapular
muscles
during
a
shoulder
rehabilitation
program.
Am
J
Sports
Med.
1992;20:128-134.
20.
Perrin
DH,
Robertson
RJ,
Ray
RL.
Bilateral
isokinetic
peak
torque,
torque
acceleration
energy,
power,
and
work
relationships
in
athletes
and
non-
athletes.
J
Orthop
Sports
Phys
Ther.
1987;9:184-189.
Journal
of
Athletic
Training
361
... Subjects wore the same clothing and footwear for both T1 and T2. Trials were administered to subjects' self-reported dominant limb only, based on the preferred limb used to kick a soccer ball (Bandy et al. 1994;Bolgla & Keskula 1997;Booher et al. 1993;Goh & Boyle 1997;Greenberger & Paterno 1995;Kovaleski et al. 1997). ...
... A possible limitation of this study is the chosen method for determining limb dominance, which was operationally de®ned as the preferred limb used to kick a soccer ball. Such an operational de®nition is frequently observed in the literature (Bandy et al. 1994;Bolgla & Keskula 1997;Booher et al. 1993;Goh & Boyle 1997;Greenberger & Paterno 1995;Kovaleski et al. 1997). However, although a recent review by Clark (2001) concluded that a dominance effect has yet to be de®nitively established in the literature, some clinicians might consider the ball kick as an example of`skill dominance' versus`stance dominance' with regard to the objective of the task. ...
... Subject demographics *Preferred limb used to kick a soccer ball(Bandy et al. 1994;Bolgla & Keskula 1997;Booher et al. 1993;Goh & Boyle 1997;Greenberger & Paterno 1995;Kovaleski et al. 1997); F, female; M, male; R, right leg; L, left leg; SD, standard deviation. ...
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Objective: To determine the intratester reliability of the adapted crossover hop for distance in uninjured subjects. Design: Within-subject between-session repeated measures with random selection from a sample of convenience. Setting: University physiotherapy laboratory. Participants: Twelve subjects (male:n=4; female: n=8; age=22·4±5·5 years; height=168·7±5·2cm; mass=65·8±8·5kg) without a history of lower limb or low back injury. Methods and Measures: Subjects performed three sub-maximal warm-up trials followed by three measured trials of the adapted crossover hop for distance utilising the self-reported dominant limb on two test sessions. The intraclass correlation coefficient (ICC) form (2,1), standard error of measurement (SEM), and 95% confidence interval (CI) were calculated utilising subjects' highest scores to determine intratester reliability and measurement precision. Results: The ICC (2,1) was 0·94. The SEM was 28·8cm. The 95% CI was 56·5cm. Conclusions: The results of this study demonstrate the adapted crossover hop for distance has high intratester reliability and acceptable measurement error in uninjured subjects. Thus, a new hop test with potential for identifying knee dysfunction in an anterior cruciate ligament (ACL)-injured population is presented. Future research should determine the reliability, measurement error, and validity of the adapted crossover hop for distance in an ACL-injured population.
... Authors of reliability studies sometimes give what they consider to be acceptable values. For example , Kovaleski and co-workers [8] cited the classic Shrout and Fleiss paper on reliability [9] to support their claim that a clinically acceptable correlation was 0.75 [8] or 0.80. [10] It turns out that Shrout and Fleiss [9] did not assess the utility of magnitudes of retest correlations. ...
... Authors of reliability studies sometimes give what they consider to be acceptable values. For example , Kovaleski and co-workers [8] cited the classic Shrout and Fleiss paper on reliability [9] to support their claim that a clinically acceptable correlation was 0.75 [8] or 0.80. [10] It turns out that Shrout and Fleiss [9] did not assess the utility of magnitudes of retest correlations. ...
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Reliability refers to the reproducibility of values of a test, assay or other measurement in repeated trials on the same individuals. Better reliability implies better precision of single measurements and better tracking of changes in measurements in research or practical settings. The main measures of reliability are within-subject random variation, systematic change in the mean, and retest correlation. A simple, adaptable form of within-subject variation is the typical (standard) error of measurement: the standard deviation of an individual's repeated measurements. For many measurements in sports medicine and science, the typical error is best expressed as a coefficient of variation (percentage of the mean). A biased, more limited form of within-subject variation is the limits of agreement: the 95% likely range of change of an individual's measurements between 2 trials. Systematic changes in the mean of a measure between consecutive trials represent such effects as learning, motivation or fatigue; these changes need to be eliminated from estimates of within-subject variation. Retest correlation is difficult to interpret, mainly because its value is sensitive to the heterogeneity of the sample of participants. Uses of reliability include decision-making when monitoring individuals, comparison of tests or equipment, estimation of sample size in experiments and estimation of the magnitude of individual differences in the response to a treatment. Reasonable precision for estimates of reliability requires approximately 50 study participants and at least 3 trials. Studies aimed at assessing variation in reliability between tests or equipment require complex designs and analyses that researchers seldom perform correctly. A wider understanding of reliability and adoption of the typical error as the standard measure of reliability would improve the assessment of tests and equipment in our disciplines.
... Sixteen recreationally active male participants (height, 175.5 ± 7.8 cm; body mass, 79.4 ± 9.1 kg; age, 27.2 ± 8.8 years) volunteered for this study. Fifteen participants were determined as right-leg dominant based on the preferred leg used to kick a ball (Kovaleski et al. 1999). Individuals with neurological conditions, cardiovascular complications, or surgery or injury to the knee structures were excluded from the study. ...
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The aim of the present study was to investigate the alterations of corticospinal excitability (motor evoked potential, MEP) and inhibition (silent period, SP) following rolling massage of the quadriceps muscles. Transcranial magnetic and femoral nerve electrical stimuli were used to elicit MEPs and compound muscle action potential (Mmax) in the vastus lateralis and vastus medialis muscles prior to and following either: i) 4 sets of 90-s rolling massage (ROLLING) or ii) rest (CONTROL). One series of neuromuscular evaluations, performed after each set of ROLLING or CONTROL, included three MEPs and one Mmax elicited every 4 s during 15 s submaximal contractions at 10% (experiment 1, n = 16) and 50% (experiment 2, n = 10) of maximal voluntary knee extensions (MVC). The MEP·Mmax-1 ratio and electromyographic activity recorded from VL at 10% MVC demonstrated significantly lower values during ROLLING than CONTROL (P < 0.05). The ROLLING did not elicit any significant changes in muscle excitability (Mmax area) and duration of TMS-induced SP recorded from any muscle or level of contraction (P > 0.05). The findings suggest that rolling massage can modulate the central excitability of the circuitries innervating the knee extensors however, the observed effects are dependent on the background contraction intensity during which the neuromuscular measurements are recorded.
... After all, voluntary fine-motor tasks such as writing, cutting, catching, and kicking exhibit strong effects of laterality. In fact, there is a multitude of evidence supporting both functional (e.g., strength and motor control) and anatomical differences at the cortical level between dominant and non-dominant limbs (15,(59)(60)(61)(62)(63)(64). It is reported that long-term preferential use of muscles results in a higher percentage of type 1 muscle fibers in the dominant hand and, in turn, changes in motor unit firing behavior (61). ...
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Clinicians frequently assume the uninjured extremity can be used as a predictor of preinjury strength for return of the injured extremity to a normal state during rehabilitation. The purpose of this study was to examine differences in bilateral isokinetic peak torque (PT) at 60 and 180 O/sec, and torque acceleration energy (TAE), average power (AP), and total work (MI) at 180 degrees /sec during knee extension and flexion, shoulder extension and flexion, and shoulder internal and external rotation in right hand dominant pitchers, swimmers, and nonathletes. PT values were greater for the right than left sides (p < 0.05) for shoulder extension (60 and 180 degrees / sec) for all three groups. Right side internal rotation (1 80 O/sec) TAE, AP, and MI values were greater than left (p < 0.05) for pitchers but not for swimmers and nonathletes. These findings question the efficacy of assuming bilateral equivalency for PT, TAE, AP, and MI measures in the prescription of therapeutic exercise for all muscle groups in all athletic and nonathletic populations. J Orthop Sports Phys Ther 1987;9(5):184-189.