Supplementary material 1
The intra-rater reliability of muscle architecture characteristics was evaluated in a subsample of 7 obese adolescent girls on two consecutive occasions (7 days apart). Relative
reliability was assessed with the Intraclass Correlation Coefficient (ICC) with 95% confidence
intervals. An ICC in the 0.8–1.0 range was considered to represent a ‘good’ reliability.
Absolute reliability was assessed with the standard error of measurement (SEM) using the
following equation: SD/√2 where SD is the standard deviation of the differences between
measurements. The coefficient of variation (CV) was also calculated for each subject using
the following equation: SD/mean. The CV was then expressed as a percentage. ICC and SEM
calculations were done using a downloadable spreadsheet (1).
Finally, the observed statistical power of statistical comparisons between lean and obese
adolescents for selected variables was calculated as recommended by Howell (2). The values
are reported in the table 3.
Table 3: Test-retest reliability of the muscle architecture measurements
Observed
statistical
power
Muscle Architecture characteristics
ICC
SEM
CV
(%)
Pennation Angle
RF
VL
VM
GL
GM
0.681
0.894
0.838
0.979
0.921
0.43
0.94
1.31
0.56
1.74
4.91
4.63
8.22
4.80
5.60
1.00
0.87
0.59
1.00
0.91
Muscle Thickness
RF
VL
VM
0.974 0.70 2.70
0.971 1.10 3.32
0.679 5.23 15.34
1.00
0.97
1.00
GL
GM
Fascicle Length
RF
VL
VM
GL
GM
Anatomical Cross Sectional Area
RF
VL
VM
GL
GM
0.973 0.33
0.966 0.88
2.84
3.72
0.45
1.00
0.935
0.944
0.613
0.874
0.814
8.26
6.72
35.78
2.11
3.61
5.60
5.47
16.30
3.54
6.49
0.95
0.22
0.24
0.14
0.14
0.988
0.982
0.776
0.981
0.951
0.21
0.97
1.54
0.21
1.03
3.94
4.69
9.53
2.68
6.09
0.90
1.00
1.00
0.98
0.50
References
1. Hopkins WG. Reliability from consecutive pairs of trials (Excel spreadsheet). In: A new view
of
statistics.
sportsci.org:
Internet
Society
for
Sport
Science,
http://www.sportsci.org/resource/stats/xrely.xls, 2000.
2. Howell DC. Power calculations for differences between two independent means. In :
Howell DC (Ed). Statistical Methods for Psychology, 8th edition. Cengage Learning,
Wadsworth, Belmont, CA, USA, 2013, pp 238-239