Acute Effects of a Brief Physical Exercise Intervention on Somatosensory Perception, Lumbar Strength, and Flexibility in Patients with Nonspecific Chronic Low-Back Pain

Abstract

Carolina Sitges,1,2 Olga Velasco-Roldán,1,3 Jaume Crespí,1 Nuria García-Dopico,1 Joan Segur-Ferrer,1 Ana María González-Roldán,1,2 Pedro Montoya1,2 1Research Institute of Health Sciences (IUNICS) and Balearic Islands Health Research Institute (IdISBa), University of the Balearic Islands (UIB), Palma, Spain; 2Departament of Psychology, UIB, Palma, Spain; 3Departament of Nursing and Physiotherapy, UIB, Palma, SpainCorrespondence: Carolina SitgesResearch Institute of Health Sciences (IUNICS), University of Balearic Islands (UIB), Carretera de Valldemossa km 7.5, Palma, 07122, SpainTel [phone]Fax [phone]Email [email protected]: Evidence-based clinical guidelines consider physical exercise one of the best nonpharmacological interventions for low-back pain (LBP), but it is necessary to clarify the exercise-induced hypoalgesia effect of different modalities of exercise in chronic pain populations.Purpose: This study focused on exploring acute changes in tactile and pressure-pain perception and lumbar strength and flexibility in patients with nonspecific chronic LBP (NSCLBP) after performing one of three 20-minute physical exercise modalities.Methods: A total of 81 patients with NSCLBP were pseudorandomly distributed into three groups of 20-minute physical exercise — 1) aerobic (n=21, mean age 42± 9.72 years, nine men), 2) stretching (n=21, mean age 40± 11.37 years, ten men), and 3) strengthening (n=20, mean age 35.80± 11.56 years, ten men) — and 4) a control group (n=19, mean age 38.64± 10.24 years, eight men), and completed self-reported questionnaires during the same period. Tactile and pressure-pain thresholds and isometric lumbar muscle endurance and flexibility were assessed before and after this brief exercise-based intervention.Results: All groups were comparable in terms of sociodemographic and clinical data, cardiovascular capacity, and self-reported data onphysical disability, mood, motivation, psychological response to stimulus properties of physical exercise, and physical activity enjoyment. Our analyses revealed higher tactile sensitivity (p< 0.001) and pressure-pain thresholds (p< 0.001) at the forefinger than other body locations. We also found lower pain sensitivity (p=0.010) and pressure pain–intensity ratings (p=0.001) and higher lumbar flexibility (p< 0.001) after intervention. After calculation of absolute pre–post differences, higher tactile sensitivity was observed at the gluteus medius muscle than the erector spinal muscle only after aerobic intervention (p=0.046).Conclusion: These results add some evidence about different modalities of exercise-induced hypoalgesia in NSCLBP. However, the fact that we also found improvements in the control group limits our conclusions.Keywords: low-back pain, exercise therapy, aerobic exercise, flexibility

Keywords

• low back pain
• exercise therapy
• aerobic exercise
• flexibility