Skip to main content

Table 2 Summary of the MF-EMG variables recorded and averaged from all 3 days

From: The potential use of spectral electromyographic fatigue as a screening and outcome monitoring tool of sarcopenic back muscle alterations

Initial median frequency
Hz average from 3 test days Mean (SE) Age Gender Age X Gender Age and gender dependant differences
  Hz F; p-value F; p- value F; p- value Age gender mean (95% CI)
All electrodes <50 91.74 (1.75) 00.84; 0.36 00.56; 0.46 0.07; 0.79 −2.20 (-06.96; 2.48) 1.88 (-2.69; 6.37)
>50 93.94 (1.66)
L5 <50 102.81 (1.72) 07.53; < 0.01 00.29; 0.59 0.10; 0.75 −7.64 (-13.17;-2.08) -1.42 (-7.20; 4.07)
>50 110.45 (2.23)
L2 <50 90.10 (2.12) 01.33; 0.25 00.51; 0.48 0.02; 0.89 −3.28 (-08.60; 1.91) 2.06 (-3.27; 7.35)
>50 93.37 (1.80)
L1 <50 80.85 (1.77) 00.08; 0.78 00.01; 0.90 0.36; 0.55 0.58 (-03.90; 4.88) 0.14 (-4.43; 4.63)
>50 80.26 (1.55)
Most negative electrode <50 75.25 (1.53) 00.08; 0.77 00.20; 0.66 0.01; 0.94 −0.62 (-04.65; 3.51) 0.98 (-3.19; 4.95)
  >50 75.87 (1.36)     
Median frequency slope decline
Hz/s average from 3 test days Mean (SE) Age Gender Age X Gender Age and gender dependant differences
  Hz/s F; p-value F; p- value F; p- value Age gender mean (95% CI)
All electrodes <50 −0.20 (0.03) 05.67; 0.02 02.06; 0.16 0.41; 0.53 −0.10 (-0.17; -0.02) -0.06 (-0.14; 0.02)
>50 −0.11 (0.02)
L5 <50 −0.24 (0.04) 04.26; 0.04 00.17; 0.68 0.01; 0.98 −0.10 (-0.19; -0.01) -0.02 (-0.12; 0.08)
>50 −0.14 (0.03)
L2 <50 −0.19 (0.03) 02.79; 0.10 01.91; 0.17 0.06; 0.80 −0.08 (-0.16; 0.02) -0.06 (-0.15; 0.03)
>50 −0.12 (0.03)
L1 <50 −0.14 (0.03) 03.79; 0.06 00.55; 0.46 0.62; 0.43 −0.07 (-0.14; -0.01) -0.03 (-0.10; 0.04)
>50 −0.07 (0.02)
Most negative electrode <50 −0.46 (0.04) 08.78; < 0.01 00.57; 0.45 0.22; 0.64 −0.15 (-0.24; -0.06) -0.04 (-0.15; 0.06)
  >50 −0.31 (0.03)     
Median frequency slope decline normalized to initial median frequency
%/s average from 3 test days Mean (SE) Age Gender Age X Gender Age and gender dependant differences
  % F; p-value F; p-value F; p- value Age gender mean (95% CI)
All electrodes <50 −0.21 (0.03) 05.14; 0.03 01.47; 0.23 0.19; 0.66 −0.10 (-0.18; -0.02) -0.06 (-0.14; 0.03)
>50 −0.12 (0.02)
L5 <50 −0.26 (0.04) 06.40; 0.01 00.17; 0.68 0.01; 0.98 −0.13 (-0.23; -0.04) -0.02 (-0.13; 0.08)
>50 −0.12 (0.03)
L2 <50 −0.20 (0.03) 02.35; 0.13 01.62; 0.20 0.16; 0.69 −0.07 (-0.16; 0.03) -0.06 (-0.15; 0.04)
>50 −0.13 (0.03)
L1 <50 −0.16 (0.03) 03.13; 0.08 00.52; 0.47 0.75; 0.39 −0.08 (-0.16; 0.00) -0.03 (-0.11; 0.05)
>50 −0.08 (0.02)
Most negative electrode <50 −0.46 (0.03) 09.15; < 0.01 00.19; 0.66 0.01; 0.99 −0.15 (-0.23; -0.05) -0.02 (-0.13; 0.07)
>50 −0.32 (0.03)
Median frequency fatigue right - left imbalances
Hz average from 3 test days Mean (SE) Age Gender Age X Gender Age and gender dependant differences
  % F; p-value F; p- value F; p- value Age gender mean (95% CI)
Uncompensated <50 8.21 (0.42) 00.01; 0.92 00.10; 0.75 2.35; 0.13 0.00 (-1.43; 1.22) 0.14 (-1.18; 1.48)
>50 8.22 (0.53)
Compensated <50 −1.63 (0.79) 00.16; 0.69 06.64; 0.01 0.62; 0.43 −0.49 (-2.81; 1.97) 2.96 (0.65; 5.13)
  >50 −1.14 (0.95)     
  1. This table further presents the results of the 2 way ANOVAS (age, gender) as well as those of the subsequent intergroup comparisons.