Background and objective Identifying factors that influence the course of low back pain (LBP) is important to help clinicians to identify those patients at higher risk of non‐recovery. The objective of this systematic review was to investigate the prognostic role of physical activity in the course of LBP. Databases and data treatment Literature searches were conducted in five electronic databases from their inception to February 2018. Prospective cohort studies investigating the influence of any type of physical activity in people with LBP were considered eligible. The primary outcomes were pain intensity and disability. Two independent reviewers extracted the data and assessed the methodological quality of the included studies. Results were stratified according to participants’ symptoms duration at baseline. Results Twelve studies were considered eligible for this review. Of these, six included patients with chronic LBP, four studies did not specify the patients’ duration of symptoms, one study included patients with acute LBP, and one study included patients with subacute LBP. Included studies were heterogeneous in terms of physical activity assessment, outcomes, follow‐up duration, and statistical methods, therefore, pooling of results was not performed. We found limited evidence to support the prognostic role of physical activity in the course of LBP. Conclusions Our review identified limited evidence supporting physical activity as a prognostic factor in LBP. Future cohort studies are needed to clarify the strength and importance of this association. Significance Despite recent research in the area, this systematic review shows that there is low quality evidence that physical activity may not be a prognostic factor for predicting pain and disability in patients with LBP.

Background The Photograph Series of Daily Activities-short electronic version (PHODA-SeV) assesses perceived harmfulness of daily activities in patients with low back pain (LBP). Although there is some evidence that the PHODA-SeV is a reliable and valid tool, its psychometric properties have not been fully investigated. Objectives To investigate the test-retest reliability, measurement error, interpretability, construct validity, and internal and external responsiveness of the PHODA-SeV in patients with chronic LBP. Methods Ninety-one patients were included in the analysis for this prospective cohort study. For reliability purposes, the PHODA-SeV was administered twice, with a 1-week interval before beginning treatment. Pain, disability, and measures of pain-related fear (ie, PHODA-SeV, Fear-Avoidance Beliefs Questionnaire [FABQ], and Tampa Scale of Kinesiophobia [TSK]) were collected before and after the 8-week treatment period. Results The PHODA-SeV showed excellent reliability (intraclass correlation coefficient model 2,1 = 0.91), without evidence of ceiling and floor effects. The construct validity analysis demonstrated fair correlations (r = 0.25-0.50) of the PHODA-SeV with the FABQ, but no correlation with the TSK (r<0.25). For internal responsiveness, the PHODA-SeV showed an effect size of 0.87 and a standardized response mean of 0.92, interpreted as a large effect (greater than 0.80). For external responsiveness, the correlations between the PHODA-SeV and changes in the TSK and FABQ were considered low, and the receiver operating characteristic curve analyses revealed an area under the curve lower than the proposed threshold of 0.70. Conclusion The PHODA-SeV is a reliable tool that can detect changes over time in pain-related fear in patients with chronic LBP undergoing physical therapy treatment. This tool, however, failed to identify those patients who did or did not improve, according to other pain-related fear measures. J Orthop Sports Phys Ther 2018;48(9):719-727. Epub 23 May 2018. doi:10.2519/jospt.2018.7864.

Background: The number of questionnaires that measures physical activity levels has increased considerably. For Brazilian population it becomes a challenge, due to the need of a rigorous translation, adaptation and testing of measurement properties. Objective: Evaluate the methodological quality and criteria of physical activity questionnaires translated to Brazilian-Portuguese. Methods: Methodological quality and quality criteria was assessed using the COnsensus-based Standards for the selection of health Measurement INstruments checklist. Results: Sixty-nine studies were included, the most frequent questionnaires investigated were the International Physical Activity Questionnaire (n = 16) and the Baecke Physical Activity Questionnaire (n = 12). Translation (n = 13), reliability (n = 37) and construct validity (n = 44) were the measurement properties commonly investigated. For reliability, most studies were rated as 'adequate' for methodological quality. The Intraclass Correlation Coefficient of the questionnaires ranged from 0.20 to 1.0. For construct validity, 31 analyses showed 'inadequate' methodological quality, due to poor description of the comparator instrument. High level

Disability measures were responsive after a course of physical therapy treatment in patients with CLBP. The lack of responsiveness in the physical activity measures might be due to the inability of these measures to detect change over time or the use of an intervention not designed to increase physical activity levels.

Aerobic fitness assessment in patients with low back pain (LBP) may help clinicians to plan how to progress the aerobic training. This was a pilot study designed to evaluate the performance of people with LBP on two different aerobic fitness tests performed on a treadmill and to compare the measure of aerobic fitness between people with LBP and healthy individuals. Ten people with LBP and 10 healthy individuals underwent two aerobic fitness protocols, the modified Bruce and maximum incremental test protocols, performed on a treadmill. Data collected during the protocols were: oxygen consumption, heart rate (HR), blood lactate concentration, respiratory quotient, rating of perceived exertion response, and pain intensity. Independent t-test and two-way analysis of variance were used respectively to assess difference between groups characteristics and physiological responses to the protocols. Our results showed that both groups were similar with regards to age (P = 0.839) or HRrest (P = 0.730) but the LBP group showed higher BMI compared to the healthy group (P = 0.031). Regarding the performance of both groups on the aerobic fitness tests, the only significant difference was reported for respiratory quotient which showed a main effect of test (P = 0.015) with higher values favoring the modified Bruce over the incremental test. Our study showed that most people with LBP are able to perform and tolerate both aerobic fitness tests but no significant differences between people with LBP and healthy individuals on both protocols were reported.