Fig 1.
Testing position in neutral standing posture with and without erector spinae vibration.
Fig 2.
Precise timeline of the experiment.
Participants were asked to perform a set of five trials (force reproduction task at 60% of their MCV) following an auditory signal which was heard every thirty seconds, for each of the vibration conditions (no vibration, 80 Hz). The order of appearance of vibration conditions (no vibration, 80 Hz vibration) differed between block 1 and block 2 (and between block 3 and block 4) to limit any vibration sequence effect.
Fig 3.
Representative data defining the Constant Error (CE) and Variable Error (VE) calculations for one experimental condition of a participant.
Table 1.
Basic data [Mean (±SD)] on cLBP and healthy study participants.
Fig 4.
Comparison of mean constant errors for both groups in each condition (mean ± standard error)
Fig 5.
Comparison of mean absolute errors for both groups in each condition (mean ± standard error)
Fig 6.
Means and standard errors of the sEMG activity of the erector spinae at L4-5 level for both groups in each condition.
The presence of back muscle fatigue led patients with cLBP to a significant decrease in sEMGRMS activity as compared to the no fatigue condition.
Table 2.
Mean (±SD) sEMG median time-frequency slope at L1 and L4-5 levels and modified Sorensen total holding time in sec for both groups.
Table 3.
Mean (±SD) level of perceived exertion during the fatigue protocol.