Table 2 Intratester Reliability of the measurement of Area of the Transverse Abdominis muscle at three Lumbar levels at rest and during the hollowing maneuver

Level

Right

Left

Right

Left

Right

Left

Right

Left

L1

2.51 (0.68)

2.76 (0.88)

0.980

(0.956–0.992)

0.979

(0.953–0.993)

0.096

(2.32, 2.70)

0.127

(2.51, 3.01)

3.825

4.601

0.265

0.353

L3

2.27 (0.64)

2.46 (0.79)

0.965

(0.921–0.987)

0.990

(0.979–0.996)

0.119

(2.04, 2.50)

0.079

(2.31, 2.62)

5.242

3.211

0.330

0.220

L5

1.97 (0.42)

2.04 (0.76)

0.962

(0.916–0.986)

0.985

(0.967–0.994)

0.083

(1.80, 2.13)

0.094

(1.86, 2.23)

4.213

4.608

0.230

0.260

Average value (SD)

Right Mean (SD) cm²

Left Mean (SD) cm²

Level

Right

Left

Right

Left

Right

Left

Right

Left

L1

2.46 (0.72)

3.02 (1.15)

0.978

(2.33–2.54)

0.977

(0.950–0.991)

0.106

(2.25, 2.66)

0.175

(2.68, 3.36)

4.711

5.795

0.295

0.484

L3

2.32 (0.58)

2.49 (0.91)

0.970

(0.933–0.989)

0.993

(0.984–0.997)

0.101

(2.12, 2.52)

0.076

(2.34, 2.64)

4.353

3.057

0.281

0.211

L5

1.84 (0.60)

2.36 (1.22)

0.991

(0.980–0.997)

0.989

(0.977–0.996)

0.057

(1.73, 1.96)

0.128

(2.11, 2.61)

3.098

5.424

0.158

0.355

Average value (SD)