Intramuscular EMG versus Surface EMG of Lumbar Multifidus and Erector Spinae in Healthy Participants

Study Design: Cross-sectional design. Objective: The aim of this study was to investigate the correlation between intramuscular EMG (iEMG) and surface EMG (sEMG) from lumbar multifidus and erector spinae muscles during (submaximal) voluntary contraction tests in healthy participants. Summary of Background Data: Low back muscle function is a key component in the stability of the lumbar spine in which an important role is attributed to the lumbar multifidus (LM). Impairments in this stabilization system are held responsible for (chronic) low back pain. LM function can be measured by iEMG and sEMG; however, in earlier studies, results from iEMG and sEMG were inconsistent. Methods: Fifteen healthy adults were included. The intervention consisted of five clinical tests: resting, submaximal contraction tests of the lower back, abdominal contraction, and a biofeedback test in which LM and erector spinae (ES) activities were compared by iEMG and sEMG. Correlations were calculated with regard to original signal, co-contraction ratio, and cross-talk ratio. Correlation coefficients for each combination of iEMG and sEMG signals were calculated, to identify original signal (i.e., activity of only the targeted muscle) and possible cross-talk. Correlations >0.75 were considered as good concurrent validity. Results: The original signals of LM showed fair to high correlation coefficients (r: 0.3–0.8). Co-contraction of LM and ES was observed during all tests, but iEMG shows more variation in the correlations (r: 0.1–0.8) compared to sEMG (r: 0.3–0.8). Significant cross-talk was observed in all tests, particularly during the biofeedback test of iEMGESversus sEMGLM and iEMGLMversus sEMGES (r = 0.8). Conclusion: Surface EMG of ES and LM are no adequate representation of LM and ES activity measured by iEMG because of moderate/high cross-talk and co-contractions. Clinical tests that aim to assess LM activity do not represent isolated LM activity. This should be taken into account in future clinical studies

Increasing Performance of Professional Soccer Players and Elite Track and Field Athletes with Peak Performance Training and Biofeedback:A Pilot Study

The aim of this pilot study was to investigate the effects of an intervention consisting of mental coaching combined with either electro encephalogram (EEG) alpha power feedback or heart rate variability (HRV) feedback on HRV, EEG outcomes and self-reported factors related to stress, performance, recovery and sleep quality in elite athletes. A prospective pilot study was performed with two distinct cohorts. Soccer players were provided with four sessions of mental coaching combined with daily HRV biofeedback (Group A); track and field athletes were provided with four sessions of mental coaching in combination with daily neurofeedback (Group B). Measurements were performed at baseline, post intervention and at 5 weeks follow-up. Objective measures: EEG and ECG. Subjective measures: Numeric Rating Scale for performance, Pittsburgh Sleep Quality Index, Rest and Stress Questionnaire and Sports Improvement-60. Group characteristics were too distinct to compare the interventions. Linear mixed models were used to analyze differences within groups over time. In Group A, significant changes over time were present in alpha power at 5 of 7 EEG locations (p <0.01-0.03). LF/HF ratio significantly increased (p = 0.02) and the concentration (p = 0.02) and emotional scale (p = 0.03) of the SIM-60 increased significantly (p = 0.04). In Group B, the HRV low frequency power and recovery scale of the REST-Q significantly increased (p = 0.02 and <0.01 resp.). Other measures remained stable or improved non-significantly. A mental coaching program combined with either HRV or EEG alpha power feedback may increase HRV and alpha power and may lead to better performance-related outcomes and stress reduction. Further research is needed to elucidate the effects of either type of feedback and to compare effects with a control group

A multiscale model of the electrohysterogram the BioModUE-PTL project

The electrohysterogram (EHG) is a promising means of monitoring pregnancy and of detecting a risk of preterm labor. To improve our understanding of the EHG as well as its relationship with the physiologic phenomena involved in uterine contractility, we plan to model these phenomena in terms of generation and propagation of uterine electrical activity. This activity can be realistically modeled by representing the principal ionic dynamics at the cell level, the propagation of electrical activity at the tissue level and then the way it is reflected on the skin surface through the intervening tissue. We present in this paper the different steps leading to the development and validation of a biophysics based multiscale model of the EHG, going from the cell to the electrical signal measured on the abdomen

Remote Monitoring for Healthcare and for Safety in Extreme Environments

In this chapter we examine the potential use of remote health monitoring using Body Area Networks (BANs) to support individuals who are working or pursuing recreational activities in extreme environments

REMOTE MONITORING FOR HEALTHCARE AND FOR SAFETY IN EXTREME ENVIRONMENTS

In this chapter we examine the potential use of remote health monitoring using Body Area Networks (BANs) to support individuals who are working or pursuing recreational activities in extreme environments. Monitoring can be defined as (periodic or continuous) measurement an