Table 4 Mean ± SD absolute and normalized root mean square values (absRMS (mV) and normRMS (% of the highest RMS values of the three maximum voluntary contractions)) of the left and right trapezius descendens surface electromyograms during standardized box lifting at day 1 and day 2, intraclass correlation coefficient (ICC3.K) values and between-day normRMS difference for left and right erector spinae

66.6 ± 36.0

59.7 ± 37.9

0.19

−6.9 ± 49.4

10.0 ± 6.5

11.0 ± 7.0

0.18

1.0 ± 9.1

80.2 ± 51.4

69.9 ± 36.5

0.87

−10.3 ± 30.0

11.2 ± 7.1

10.9 ± 6.2

0.64

−0.3 ± 6.8

90.7 ± 57.3

70.8 ± 48.2

0.31

−19.9 ± 67.6

13.3 ± 9.7

12.4 ± 6.8

0.23

−0.9 ± 11.1

90.0 ± 69.3

84.9 ± 40.3

0.78

−5.1 ± 47.7

12.8 ± 9.2

13.5 ± 8.0

0.62

0.7 ± 9.1

71.9 ± 51.5

53.0 ± 34.8

0.08

−18.9 ± 60.7

10.8 ± 8.7

9.6 ± 6.4

0.12

−1.2 ± 10.5

93.8 ± 67.7

76.9 ± 48.0

0.84

−16.9 ± 43.1

13.0 ± 9.2

12.0 ± 8.1

0.64

−1.0 ± 8.9

148.7 ± 89.1

126.0 ± 78.0

0.14

−22.7 ± 113.8

21.7 ± 14.5

21.5 ± 9.5

0.40

−0.2 ± 15.0

169.0 ± 91.9

156.3 ± 84.7

0.77

−12.7 ± 76.7

23.2 ± 11.9

24.4 ± 17.7

0.62

1.1 ± 15.8

231.4 ± 156.3

187.0 ± 111.3

0.57

−44.4 ± 148.5

32.4 ± 22.9

32.4 ± 15.3

0.36

0.0 ± 24.4

267.0 ± 175.8

223.1 ± 121.3

0.83

−43.9 ± 114.9

36.1 ± 20.9

36.5 ± 28.5

0.76

0.4 ± 21.8

153.6 ± 120.3

124.1 ± 72.1

0.52

−29.5 ± 112.7

21.4 ± 17.2

20.6 ± 8.7

0.11

−0.8 ± 18.7

216.6 ± 157.3

182.4 ± 125.6

0.89

−34.2 ± 88.3

32.0 ± 26.6

30.0 ± 28.8

0.57

−2.0 ± 30.5

308.0 ± 223.7

236.0 ± 128.4

0.47

−72.0 ± 214.2

43.2 ± 32.1

38.4 ± 13.3

0.30

−4.8 ± 31.5

344.7 ± 250.3

281.8 ± 160.0

0.84

−62.9 ± 157.9

46.9 ± 29.6

43.9 ± 35.3

0.83

−3.0 ± 24.6

78.9 ± 45.6

60.7 ± 41.0

0.36

−18.2 ± 54.2

11.7 ± 7.6

11.4 ± 7.9

0.37

−0.3 ± 9.7

81.0 ± 69.4

75.5 ± 36.7

0.80

−5.5 ± 45.3

10.9 ± 8.2

11.7 ± 6.5

0.76

0.8 ± 6.5

91.3 ± 60.3

75.4 ± 56.6

0.60

−15.9 ± 62.5

13.5 ± 10.5

13.6 ± 10.2

0.49

0.1 ± 12.1

86.9 ± 61.7

81.9 ± 46.9

0.73

−5.0 ± 50.6

12.0 ± 8.1

13.5 ± 9.7

0.66

1.5 ± 9.0

70.1 ± 41.2

61.7 ± 41.7

0.35

−8.4 ± 52.2

10.0 ± 5.7

11.0 ± 7.3

0.31

1.0 ± 8.4

92.6 ± 70.8

85.2 ± 49.4

0.80

−7.4 ± 49.8

12.2 ± 8.2

12.9 ± 8.5

0.74

0.7 ± 7.6

160.0 ± 96.3

156.8 ± 80.1

0.53

−3.2 ± 100.1

22.8 ± 14.2

28.7 ± 16.6

0.28

5.9 ± 20.0

178.3 ± 114.1

174.9 ± 85.3

0.86

−3.4 ± 89.5

26.2 ± 19.3

27.4 ± 18.7

0.58

1.2 ± 20.7

216.2 ± 128.4

181.2 ± 92.0

0.67

−35.0 ± 111.6

30.1 ± 17.7

32.3 ± 17.2

0.33

2.2 ± 22.1

232.3 ± 134.7

228.3 ± 136.0

0.88

−4.0 ± 69.6

35.3 ± 28.8

36.9 ± 31.3

0.45

1.6 ± 35.8

177.6 ± 101.4

155.7 ± 77.3

0.59

−21.9 ± 97.5

25.0 ± 14.3

27.9 ± 15.1

0.42

2.9 ± 17.8

241.5 ± 156.2

193.0 ± 102.1

0.84

−48.5 ± 99.2

35.5 ± 26.0

31.5 ± 23.5

0.67

−4.0 ± 24.8

337.5 ± 203.4

304.2 ± 176.7

0.55

−33.3 ± 212.1

45.3 ± 23.9

53.8 ± 30.9

0.50

8.5 ± 31.8

336.1 ± 171.7

303.5 ± 171.8

0.83

−32.6 ± 131.1

47.9 ± 28.0

49.3 ± 41.0

0.53

1.4 ± 39.7