Study Design. Randomized prevention trial.
Objective. To compare the long-term effect of strengthening versus flexibility exercises and to evaluate the additional effect of abdominal bracing in recurrent low back pain (LBP).
Summary of Background Data. No conclusions could be made regarding appropriate exercise types or parameters in recurrent LBP. Abdominal bracing increases trunk stiffness; however, its long-term effect has not been evaluated in recurrent LBP yet.
Methods. Six hundred patients with recurrent LBP participated. They were randomized into 4 groups—150 patients (age: 42.5 ± 12.7) performed strengthening exercises; 150 patients (age: 41.3 ± 11.5) performed flexibility exercises; 150 patients (age: 41.0 ± 13.2) performed strengthening exercises and used abdominal bracing in daily activities/exercises; and 150 patients (age: 40.6 ± 12.3) performed flexibility exercises and used abdominal bracing in daily activities/exercises. At the beginning of the study and at the end of 10 consecutive years were recorded 6 outcomes—frequency, intensity, and duration of pain, as well as frequency, intensity, and duration of exercises.
Results. Regarding the first 4 outcomes—all groups showed improvement from the beginning to the second year, but worsening from the second to the 10th year; there was no difference between strengthening and flexibility groups; bracing groups showed better results versus nonbracing groups. Intensity, frequency, and duration of the pain correlated with each other and with frequency of the exercises, but not with exercise duration or intensity.
Conclusion. The exercise frequency is more important than the type, duration, or intensity of the exercise. Abdominal bracing adds to the exercise effect. It could be considered as a “preliminary muscle back belt on demand” increasing the trunk stiffness and the frequency of the trunk muscle contractions/cocontractions without interruption of daily activities, which may remind/convince the patients to exercise more frequently. Frequent exercising and bracing seems effective long-term prevention advices in recurrent LBP.
Level of Evidence: 2