Electromyographic fatigue evaluation of back and hip extensor muscles and its relationship with anthropometric characteristic of athletes with chronic low back pain

Aim. The aim of the study was to measure back and hip extensor muscle fatigue during Sorensen back endurance test in chronic low back pain (CLBP) athletes and healthy controls, and investigation of relationship between the back and hip extensor muscle fatigability and subject's anthropometric characteristics. Methods. Thirty male wrestlers (N.=15 per group) participated in this study in two groups as athletes with chronic low back pain (mean age 24.06 yrs) and healthy athletes (mean age 24.04 yrs) after giving their written informed consent. Subjects performed Sorensen back endurance test until exhaustion, while electromyographic (EMG) power spectrum median frequency compression over time (ME slope) as indicator of the erector spina muscle fatigability, and endurance time were recorded. Results. The results showed that the endurance time was shorter (P<0.05) in CLBP athletes compared to the healthy subjects. EMG power spectrum MF slope was higher (P<0.05) in CLBP group than in healthy subjects. Correlation analysis showed significant positive relation between BMI and endurance time in CLBP athletes (r=0.6.1) Body mass and BMI correlated moderate positively with ME slope of erector spinae muscles (r=0.62-0.76) in both groups. Discussion. The chronic low back pain athletes were weaker and fatigued faster than the healthy controls. The EMG fatigue analysis results suggest that the gluteus maximus muscles are more fatigable in chronic low back pain athlete than in healthy control subjects during a sustained back extension endurance test., Conclusion. Therefore, it should be emphasized in rehabilitation strategies to improve the endurance of back and hip extensor and reduce muscle fatigability and low back pain in athlete with CLBP. The possible association between BMI and body mass may suggest need for education regarding weight reduction as useful implement in chronic low back pain prevention.