The Influence of an Eight Week, Structured Strength-endurance Training on Pain Perception and Health-related Quality of Life in Patients with Non-specific Low Back Pain: Who Profits?

Abstract

Purpose: Non-specific low back pain is one of the leading public health problems worldwide. With respect to the duration of pain, it is generally divided into acute, subacute, and chronic. While physical exercises are promoted as a non-pharmacologic treatment in the chronic state, the actual literature refuses specific exercises in the acute phase. However, there is a lack of data concerning the effect of structured training programs in these patients. The present study investigated the influence of a structured and supervised strength-endurance program on pain intensity and quality of life in non-specific, acute, subacute, and chronic low back pain patients. Methods: 1147 adult patients of both sexes entered the multi-centered, controlled, and randomized training intervention. The control group was advised to maintain a physically active lifestyle. The eight-week, two-times per week training intervention consisted of a circle with eight strength-endurance and two endurance exercises for back-pain relevant muscle groups. In each session, the circle was performed two-times with 60 seconds and 240 seconds durations for the strength-endurance and endurance exercises, respectively. The break between each exercise lasted 30 seconds. Anthropometric data, comorbidities, regular physical activities, actual physiotherapeutic and medical treatment, probability of pain-chronification, pain quality and quantity, and health related physical and mental quality of life was evaluated at the beginning, after four weeks, and finally after eight weeks by means of online-questionnaires. Results: The drop-out rate at the end of intervention amounted to 14.4% in the control group and 30% in the training group. None of the obtained parameters had a prognostic meaning for adherence of patients. Finishers: In both the acute, subacute, and chronic stages of the training group a significant and clinically important reduction in pain intensity could be obtained while a smaller, clinically not important but still statistically significant reduction occurred in the acute and subacute control group. No improvement occurred in the chronic control group. Simultaneously, a significant increase in health related physical quality of life was observed in all stages of the training group. Discussion: In contrast to the main part of the existing literature, training was in all stages of non-specific low back pain superior to an exclusively active lifestyle. Especially for acute low back pain the actual guidelines does not promote exercise as a treatment. The discrepancy may at least in part be explained by the kind and quality of exercise interventions used in previous studies. Conclusion: Structured medical training therapies should be recommended as an essential treatment in all stages of non-specific low back pain.