Immediate Exercise-Induced Hypoalgesia in Patients With Chronic Low Back Pain

Study Overview
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Brief Summary
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The main objective of this study is: • To evaluate the immediate hypoalgesic effect of an aerobic exercise session of different intensities in patients with chronic low back pain; The secondary objective is: • To explore whether pain intensity, level of physical activity, functionality, catastrophizing, kinesiophobia, anxiety and depression interfere with the immediate hypoalgesic effect of exercise.

Detailed Description
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There will be 3 groups of participants, an asymptomatic control group that will not perform any exercise and two groups of individuals with low back pain. One group will perform exercise at 90% VO2máx and the other at 60% VO2máx. All the three groups will be assessed at baseline for pressure pain threshold, pain intensity, pain phenotype, disability, kinesiophobia, catastrophizing, anxiety and depression, physical activity, and aerobic capacity. In addition, pressure pain threshold and pain intensity will also be assessed at post-intervention.

Official Title
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Immediate Exercise-Induced Hypoalgesia in Patients With Chronic Low Back Pain

Conditions
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Low Back Pain

Intervention / Treatment
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* Other: Exercise at 60% vo2
* Other: Exercise at 90% vo2


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All groups: age between 18 and 65 years old Participants with low back pain: non-specific LBP (defined as pain between the costal margins and the inferior gluteal folds, which is usually accompanied by painful limitation of movement and may be associated with pain referred down to the leg) Exclusion Criteria: All groups: presence of pathology of the nervous system, cardiovascular or carcinogenic, rheumatic diseases (for example, rheumatoid arthritis), fibromyalgia, previous history of lumbar surgery, medication that affects or alters heart rate, any contraindication to exercise and pregnancy.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Exercise at 60% vo2<br>This arm will receive 15 minutes of exercise at 60% VO2 max. | Other: Exercise at 60% vo2<br>* 15 minutes of exercise at 60% VO2 max.<br>|
| Experimental: Exercise at 90% vo2<br>This arm will receive 15 minutes of exercise at 90% VO2 max. | Other: Exercise at 90% vo2<br>* 15 minutes of exercise at 90% VO2 max.<br>|
| No Intervention: No intervention<br>No intervention | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pressure pain threshold | Pressure pain threshold measured with an algometer in Kgf | Baseline | 
| Pressure pain threshold | Pressure pain threshold measured with an algometer in Kgf | Post-intervention (approximately 45 minutes after baseline) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Aerobic capacity | Measured with the Chester Step Test (CST) which gives aerobic capacity and allows the calculation of percentage of VO2 max. | Baseline | 
| Physical activity | Measured with the International Physical Activity Questionnaire. Results can be reported in categories (low activity levels, moderate activity levels or high activity levels) or as a continuous variable (MET minutes a week). | Baseline | 
| Anxiety and depression | Measured with the Hospital Anxiety and Depression Scale. This scale has 2 subscales, one for Anxiety and one for Depression both scored 0 to 21 and higher values represent higher levels of anxiety and depression. | Baseline | 
| Catastrophizing | Measured with the Catastrophizing Scale (range 0-52 and higher values are indicative of higher pain catastrophizing) | Baseline | 
| Fear of movement | Measured with the TAMPA Scale of Kinesiophobia (range: 13-52 and higher values are indicative of higher levels of fear of movement) | Baseline | 
| Disability | Measured with the Roland Morris Disability Questionnaire (range: 0 to 24, with higher values indicating higher disability) | Base | 
| Pain phenotype | Measured with the Pain DETECT Scale. The final score between -1 and 38, indicates the likelihood of a neuropathic pain component. A score of ) 12 indicates that pain is unlikely to have a neuropathic component (< 15%), while a score of * 19 suggests that pain is likely to have a neuropathic component (> 90%). | Baseline | 
| Symptoms of central sensitization | Measured with the Central Sensitization Inventory. Score ranges from 0 to 100 and higher scores indicate higher symptoms of central sensitization. | Baseline | 
| Pain intensity | Assessed using the Visual Analogue Scale from 0 to 100 mm | Baseline | 
| Pain intensity | Assessed using the Visual Analogue Scale from 0 to 100 mm | Post-intervention (approximately 45 minutes after baseline) |