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Study Design. A report on plenary presentations and discussions of an expert panel and workshop (Exercise as a treatment for subacute low back pain) that was held at the Amsterdam Forum VIII on Low Back Pain Research in Primary Care.Objective. To highlight important issues regarding the design, conduct, and reporting of exercise trials and to provide suggestions for improvement in each domain.Summary of Background Data. Despite improvements in the methodologic quality of randomized clinical trials on low back pain (LBP), current trials on exercise therapy still show methodologic flaws in the design and reporting of studies.Methods. Important issues in the design, conduct, and reporting of exercise trials for LBP were introduced by 4 presenters, and this was followed by a group discussion among 40 attendees. Conclusions and recommendations were extracted by the workshop panelists and summarized in this paper.Results. Workshop discussion led to the following recommendations: (1) specify a theoretical framework for exercise therapy for designing the intervention and selecting appropriate treatment efficacy measures; (2) to overcome blinding problems in exercise trials, include sham interventions and assess the success of blinding; (3) evaluate the role of patient-provider interactions through the use of self-report or observational measures; (4) to assure quality of treatment, use exercise interventions that reference existing exercise guidelines; (5) use subgroup analyses to identify subgroups of patients most likely to benefit; (6) in reporting exercise trials, include an extensive description of the study population, a detailed exercise protocol, and some measure of patient compliance; (7) further categorization of exercise interventions is needed, in terms of concept, mode, intensity, duration, frequency, and length; and (8) trial registration and publication of detailed study protocols may help to strengthen the evidence-based concerning exercise therapy for LBP.Conclusion. By paying proper attention to issues concerning the design and reporting of exercise protocols when conducting future exercise trials, research may provide a stronger evidence basis for recommending or not recommending various exercise therapies for LBP. [ABSTRACT FROM AUTHOR]

Question: Is eight weeks of high-intensity strengthening of the isolated lumbar extensors more effective than low-intensity strengthening or no strengthening? Are any gains maintained 16 weeks later? Design: Randomised, three-arm trial with concealed allocation, assessor blinding, and intention-to-treat-analysis. Participants in the waiting list control group were randomised again, after the first 8 weeks, to either the high-intensity or the low-intensity strengthening program. Participants: Sixty-five army personnel with non-specific chronic low back pain. Intervention: The high-intensity training group received 10 sessions of 15 to 20 repetitions for the isolated lumbar extensor muscles. The low-intensity training group received a nonprogressive, low-intensity resistance protocol. Outcome measures:Primary outcomes were global perceived effect and disability. Secondary outcomes were health-related quality of life, fear of movement/(re-)injury, and isometric lumbar extensor muscle strength. Measures were taken before and after the training and 16 weeks later. Results: At eight weeks, SF-36 overall score was on average 7% (95% CI 1 to 13) greater in the high-intensity training group compared with the low-intensity training group and the waiting list control group, and self-assessed decrease of back symptoms was on average 39% (95% CI 14 to 64) greater in the high-intensity training group compared with the waiting list control group. There was no difference in improvement between the groups for any other outcome at 8 weeks or 24 weeks. Conclusions: Although some beneficial effects were found, the results of this high-intensity strengthening program of the isolated lumbar extensor muscles do not clearly support the generally-claimed beneficial influence of exercise for chronic non-specific low back pain. [ABSTRACT FROM AUTHOR]

Introduction: Mid-portion Achilles tendinopathy (mid-AT) is common in soldiers, significantly impacting activity levels and operational readiness. Currently, Victorian Institute of Sport Assessment-Achilles (VISA-A) represents the gold standard to evaluate pain and function in mid-AT. Our objective was to estimate VISA-A thresholds for minimal important change (MIC) and patient-acceptable symptom state for return to the presymptom activity level (PASS-RTA), in soldiers treated with a conservative programme for mid-AT., Methods: A total of 40 soldiers (40 unilateral symptomatic Achilles tendons) were included in this prospective cohort study. Pain and function were evaluated using VISA-A. Self-perceived recovery was assessed with the Global Perceived Effect scale. The predictive modelling method (MIC-predict) was used to estimate MIC VISA-A post-treatment (after 26 weeks) and after 1 year of follow-up. The post-treatment PASS-RTA VISA-A was estimated using receiver operating characteristic statistics. The PASS-RTA was determined by calculating Youden's index value closest to 1., Results: The adjusted MIC-predict was 6.97 points (95% CI 4.18 to 9.76) after 26 weeks and 7.37 points (95% CI 4.58 to 10.2) after 1 year of follow-up post-treatment.The post-treatment PASS-RTA was 95.5 points (95% CI 92.2 to 97.8)., Conclusions: A VISA-A change score of 7 points, post-treatment and at 1 year of follow-up, can be considered a minimal within-person change over time, above which soldiers with mid-AT perceive themselves importantly changed. Soldiers consider their symptoms to be acceptable for return to their presymptom activity level at a post-treatment VISA-A score of 96 points or higher., Trial Registration Number: NL69527.028.19., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ Group.)

Introduction: Mid-portion Achilles tendinopathy (mid-AT) is currently the preferred term for persistent Achilles tendon pain, defined as located 2-7 cm proximal to the calcaneus, and with loss of function related to mechanical loading. Histologically, mid-AT is considered to represent a degenerative condition. Therefore, monitoring of tendon structure additional to pain and function may be warranted, to prevent progression of degeneration or even tendon rupture. The aim of this study was to determine the association between pain and function, relative to the Achilles tendon structure, in soldiers treated with a conservative programme for mid-AT., Methods: A total of 40 soldiers (40 unilateral symptomatic tendons) were included in this study. Pain and function were evaluated with the Victorian Institute of Sports Assessment -Achilles (VISA-A) questionnaire. Tendon structure was quantified using ultrasound tissue characterisation (UTC). We quantified both the Achilles tendon mid-portion (2-7 cm) and the area of maximum degeneration (AoMD) within the tendon mid-portion. VISA-A and UTC measurements were taken at baseline and after 26 weeks of follow-up. Spearman's rho was used to determine the correlation between VISA-A and UTC. Correlations were calculated for baseline, follow-up and change score values., Results: Negligible correlations were found for all analyses, ranging from -0.173 to 0.166 between mid-portion tendon structure and VISA-A, and from -0.137 to 0.150 between AoMD and VISA-A. While VISA-A scores improved, on average, from 59.4 points at baseline to 93.5 points at follow-up, no detectable improvement in aligned fibrillar structure was observed in our population., Conclusion: Pain and function are poorly associated with Achilles tendon structure in soldiers treated with a conservative programme for mid-AT. Therefore, we advise clinicians to use great caution in communicating relationships between both clinical entities., Trial Registration Number: NL69527.028.19., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Introduction: Tendon structure in mid-portion Achilles tendinopathy (mid-AT) appears poorly associated with symptoms. Yet, degenerative tendon changes on imaging have been associated with an increased risk of mid-AT. We aimed to investigate the prognostic value of ultrasound tissue characterisation (UTC) for a mid-AT recurrence in service members reporting to be recovered following standard care., Methods: Mid-portion aligned fibrillar structure was quantified post-treatment in 37 participants. Recurrences were determined after 1 year of follow-up, based on self-perceived recurrence (yes/no) combined with a decrease in post-treatment Victorian Institute of Sports Assessment-Achilles score of at least the minimal important change of 7 points. Receiver operating characteristic curve analyses were used to determine a threshold for dichotomisation of outcomes for aligned fibrillar structure (normal representation/under-representation). Using multivariable logistic regression, the association between a mid-AT recurrence (yes/no) and the dichotomised aligned fibrillar structure was determined., Results: Eight participants (22%) experienced a recurrence. The threshold for aligned fibrillar structure was set at 73.2% (95% CI: 69.4% to 77.8%) according to Youden's index. Values below this threshold were significantly associated with a mid-AT recurrence (odds ratio (OR) 9.7, 95% CI: 1.007 to 93.185). The OR for a mid-AT recurrence was 1.1 (95% CI: 1.002 to 1.150) for each additional month of symptom duration. The explained variance of our multivariable logistic regression model was 0.423; symptom duration appeared to be a better predictor than aligned fibrillar structure., Conclusions: This study identified mid-portion aligned fibrillar structure and symptom duration as potential prognostic factors for a mid-AT recurrence in military service members. The threshold for aligned fibrillar structure of 73.2% can guide preventative interventions (eg, training load adjustments or additional tendon load programmes) aiming to improve tendon structure to minimise the future recurrence risk., Trial Registration Number: https://www.toetsingonline.nl/to/ccmo_search.nsf/Searchform?OpenForm, file number ToetsingOnline NL69527.028.19., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

This study aimed to evaluate the effectiveness of glasses that emit blue light in reducing the need for recovery, general fatigue, and stress levels in security guards who work night shifts. Light manipulation is seen as a promising strategy to mitigate complaints related to shift work, such as sleepiness and impaired cognitive performance. In a randomized controlled cross-over study design, 86 Dutch security guards used light-emitting glasses (exposure duration: 30 min) during night shifts in a five week period versus a five week control period without glasses. Measurements (Need for Recovery Scale; Checklist Individual Strength; stress level assessed by a fitness tracker) were performed at baseline, at five weeks, and again at 11 weeks. The chronotype was measured at baseline as a potential covariate. A mixed model for repeated measure analyses showed no significant reduction in the need for recovery, nor a reduction in general fatigue scores, during the intervention period. Paired Samples T-Test analyses showed no significant changes in stress levels for the intervention period. Conclusively, blue light exposure using light-emitting glasses for security guards during night shifts showed no directly measurable effect on the reduced need for recovery, overall fatigue, and stress levels.

Introduction: Overuse injuries often start with a musculoskeletal complaint, which can progress over time to an injury. Little or no information is known about the development and severity of overuse injuries in military recruits. This study describes the musculoskeletal complaints in Dutch military recruits during their basic training and examines potential predictive factors for dropout due to injury., Methods: In this prospective cohort study, Dutch military recruits reported complaints of the lower body weekly using a Numeric Rating Scale (NRS) pain score chart during their basic training. Number, location and severity of complaints during each of the first 12 weeks of basic training were analysed., Results: Of the 930 recruits, 61% reported an NRS pain score of 3 or higher and 34% reported an NRS pain score of 5 or higher at least once. Complaints were mostly reported in the foot and ankle region and least reported in the upper leg region. Injury dropouts (11%) showed significantly higher proportions of complaints and higher maximal pain scores throughout most weeks of basic training. The maximal NRS pain score of the first two weeks was the strongest predictor of dropping out due to injury., Conclusions: Recruits who drop out due to injury report more severe complaints throughout basic training. Focusing on musculoskeletal complaints in the first phase of training seems helpful to identify recruits who are at risk of developing an injury., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: Ultrasound tissue characterization (UTC) is used to visualize and quantify the Achilles tendon structure. We investigated the intra-rater and inter-rater reliability of UTC for quantifying the midportion tendon structure and the area of maximum degeneration (AoMD) in military personnel with midportion Achilles tendinopathy., Method: UTC scans of 50 patients (16-60 years) were processed twice by rater 1 and once by rater 2. First, the midportion tendon structure was quantified and subsequently the AoMD. The intraclass correlation coefficient (ICC) was calculated for echo-types I, II, III, IV, aligned fibrillar structure (echo-types I + II), and disorganized tendon structure (echo-types III + IV)., Results: For midportion tendon structure, all ICC values were excellent for intra-rater reliability (range: 0.97 to 0.99) and inter-rater reliability (range: 0.98 to 0.99). Regarding the AoMD, intra-rater reliability showed excellent ICC values for all echo-types (range: 0.94 to 0.98) except for echo-type II (0.85). Inter-rater reliability showed excellent ICC values for all echo-types (range: 0.92 to 0.98)., Conclusion: Processing of UTC scans is highly reliable in quantifying the midportion Achilles tendon structure and the AoMD., Competing Interests: All authors declare that they have no conflicts of interest relevant to the content of this study., (Copyright © 2022 Marc Adriaan Paantjens et al.)

Objectives This study aims to evaluate the effectiveness of a "blended" workplace health-promotion intervention, alongside identification of key components beneficial for future implementation strategies. Methods Within a cluster randomized controlled trial, 491 employees at increased risk of cardiovascular disease were allocated to the limited (N=217; 9 clusters) or extensive (N=274; 8 clusters) intervention. The extensive intervention consisted of motivational interviewing (MI) within the framework of a web-based health risk assessment (HRA), a blended care approach. The limited intervention received solely the web-based HRA. Occupational health physicians (N=21) within three organizations delivered the intervention. Implementation components investigated included: HRA (reach and participation), newsletters (percentage read), and MI sessions (number and quality). MI quality was determined by scoring audiotaped MI sessions, using the MI treatment integrity code. After 6 and 12 months, effects on participation in health-promotion activities and its associations with components of implementation were determined by mixed-effects models. Results Over 80% of employees participated in health-promotion activities, with an additional 8% in the extensive compared to the limited group. In the extensive intervention, those with more or better quality MI sessions were more likely to participate in health-promotion activities. Increased MI quality was associated with sustained participation. Conclusions This study suggests that participation in health-promotion activities can be increased by adding MI to a web-based approach and improving the quality of the MI delivered. Interventions with MI should include optimized delivery and quality of MI sessions.

Background: Web-based lifestyle interventions at the workplace have the potential to promote health and work productivity. However, the sustainability of effects is often small, which could be enhanced by adding face-to-face contacts, so-called 'blended care'. Therefore, this study evaluates the effects of a blended workplace health promotion intervention on health and work outcomes among employees with increased cardiovascular risk., Methods: In this multicentre cluster-randomised controlled trial (PerfectFit), 491 workers in 18 work units from military, police, and a hospital with increased cardiovascular risk were randomised into two intervention groups. The limited intervention (n = 213; 9 clusters) consisted of a web-based Health Risk Assessment with advice. In the extensive intervention (n = 271; 8 clusters), coaching sessions by occupational health physicians using motivational interviewing were added. One cluster dropped out after randomisation but before any inclusion of subjects. Primary outcome was self-rated health. Secondary outcomes were body weight, body mass index (BMI), work productivity, and health behaviours. Follow-up measurements were collected at 6 and 12 months. Effect sizes were determined in mixed effects models., Results: At 12 months, the extensive intervention was not statistically different from the limited intervention for self-rated health (4.3%; 95%CI -5.3-12.8), BMI (- 0.81; 95%CI -1.87-0.26) and body weight (- 2.16; 95%CI -5.49-1.17). The within-group analysis showed that in the extensive intervention group body weight (- 3.1 kg; 95% CI -2.0 to - 4.3) was statistically significantly reduced, whereas body weight remained stable in the limited intervention group (+ 0.2 kg; 95% CI -1.4 to 1.8). In both randomised groups productivity loss and physical activity increased and excessive alcohol use decreased significantly at 12 months., Conclusions: There were no effects on self-rated health, body weight, and BMI. However, within the group with web-based tailored Health Risk Assessment including personalized advice body weight reduced significantly. Adding motivational coaching is promising to reduce body weight., Trial Registration: Retrospectively registered at the Netherlands Trial Registry with number NTR4894 , at Nov 14 2014.

Background: It is assumed that low back pain patients who use pain-avoiding immobilizing strategies may benefit from specific back flexion and extension exercises aimed at reducing sagittal lumbar hypomobility. The aim of this study was to test this potential working mechanism in chronic low back pain patients undergoing lumbar extensor strengthening training., Methods: A single-group prospective cohort design was used in this study. Patients with persistent low back complaints for at least 2 years were recruited at a specialized physical therapy clinics center. They participated in a progressive 11-week lumbar extensor strength training program, once a week. At baseline, sagittal lumbar mobility in flexion and extension was measured with a computer-assisted inclinometer. Self-rated pain intensity was measured using a visual analogue scale, back-specific functional status was assessed with the Quebec Back Pain Disability Scale and the Patient Specific Complains questionnaire., Results: Statistically significant improvements were found in pain (28% decrease) and functional disability (23% to 36% decrease). Most progress was seen in the first 5 treatment weeks. Lumbar mobility in flexion showed non-significant increases over time (+12%). Pre-post treatment changes in flexion and extension mobility did not contribute significantly to the models. The retained factors together explained 15% to 48% of the variation in outcome., Conclusions: Specific lumbar strengthening showed clinically relevant improvements in pain and disability in patients with persistent chronic low back pain. These improvements did not necessarily relate to improvements in lumbar mobility. Parameters representing other domains of adaptations to exercise may be needed to evaluate the effects of back pain management.

Overuse injuries of the leg are a common problem for young soldiers. This article reviews the literature concerning the prevention and treatment of exercise related leg pain in military settings and presents the latest developments in proposed mechanisms and treatments. Current practice and treatment protocols from the Dutch Armed Forces are reviewed, with an emphasis on the most prevalent conditions of medial tibial stress syndrome and chronic exertional compartment syndrome. The conclusion is that exercise related leg pain in the military is an occupational problem that deserves further study., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background and Purpose: The long-term effectiveness of both operative and non-operative management approaches for Chronic Exertional Compartment Syndrome of the lower legs (CECS) is moderate at best. Positive outcomes have recently been reported on modifying running technique in individuals with CECS. The purpose of this case series was to evaluate a training program aimed at changing marching technique in individuals with CECS, based on principles that aim to eliminate heel strike and decrease impact during foot strike., Study Design: Case series., Methods: Six service members with CECS underwent a five-week training program aimed at modifying marching technique. The program was comprised of foot/lower leg strengthening exercises, perception drills, and treadmill/outdoor marching bouts. Self-assessed leg condition, march endurance performance, and kinematic/kinetic measurements were assessed at baseline (T 0 ), post-treatment (T 5 ), and nine months post-intervention (T 40 )., Results: Moderate to fair pre- to post improvements on the self-assessed leg condition outcomes were demonstrated for most participants (4% to 73% improvements). These scores continued to improve until the 9 months follow-up. Marching performance improved during the intervention period in all but one subject, ranging from 6% to 38% improvement in marching time. Kinematic and kinetic data showed pre- to post-intervention changes that were reflective of the marching technique modification in most subjects. Post-intervention pain profiles of participants during marching showed that, in most subjects, the onset of leg pain was delayed compared to baseline., Conclusions: A five-week intervention aimed at altering marching technique has demonstrated moderately promising results in a group of service members with CECS of the lower legs who had previously undergone other conservative management interventions without success. Due to the relatively small sample size and the variability in subject outcomes, further research is warranted., Level of Evidence: 4.

Background: Previous studies have reported on the promising effects of changing running style in patients with chronic exertional compartment syndrome (CECS) using a 6-week training program aimed at adopting a forefoot strike technique. This study expands that work by comparing a 6-week in-house, center-based run training program with a less extensive, supervised, home-based run training program (50% home training)., Hypothesis: An alteration in running technique will lead to improvements in CECS complaints and running performance, with the less supervised program producing less dramatic results., Study Design: Cohort study; Level of evidence, 3., Methods: Nineteen patients with CECS were prospectively enrolled. Postrunning intracompartmental pressure (ICP), run performance, and self-reported questionnaires were taken for all patients at baseline and after 6 weeks of running intervention. Questionnaires were also taken from 14 patients (7 center-based, 6 home-based) 4 months posttreatment., Results: Significant improvement between preintervention and postintervention rates was found for running distance (43%), ICP values (36%), and scores on the questionnaires Single Assessment Numeric Evaluation (SANE; 36%), Lower Leg Outcome Survey (LLOS; 18%), and Patient Specific Complaints (PSC; 60%). The mean posttreatment score on the Global Rating of Change (GROC) was between +4 and +5 ("somewhat better" to "moderately better"). In 14 participants (74%), no elevation of pain was reported posttreatment, compared with 3 participants (16%) at baseline; in all these cases, the running test was aborted because of a lack of cardiorespiratory fitness. Self-reported scores continued to improve 4 months after the end of the intervention program, with mean improvement rates of 48% (SANE), 26% (LLOS), and 81% (PSC). The mean GROC score improved to +6 points ("a great deal better")., Conclusion: In 19 patients diagnosed with CECS, a 6-week forefoot running intervention performed in both a center-based and home-based training setting led to decreased postrunning lower leg ICP values, improved running performances, and self-assessed leg condition. The influence of training group was not statistically significant. Overall, this is a promising finding, taking into consideration the significantly reduced investments in time and resources needed for the home-based program.

The objective of this study was to report on secondary analyses of a merged trial dataset aimed at exploring the potential importance of patient factors associated with clinically relevant improvements in non-acute, non-specific low back pain (LBP). From 273 predominantly male army workers (mean age 39 +/- 10.5 years, range 20-56 years, 4 women) with LBP who were recruited in three randomized clinical trials, baseline individual patient factors, pain-related factors, work-related psychosocial factors, and psychological factors were evaluated as potential prognostic variables in a short-term (post-treatment) and a long-term logistic regression model (6 months after treatment). We found one dominant prognostic factor for improvement directly after treatment as well as 6 months later: baseline functional disability, expressed in Roland-Morris Disability Questionnaire scores. Baseline fear of movement, expressed in Tampa Scale for Kinesiophobia scores, had also significant prognostic value for long-term improvement. Less strongly associated with the outcome, but also included in our final models, were supervisor social support and duration of complaints (short-term model), and co-worker social support and pain radiation (long-term model). Information about initial levels of functional disability and fear-avoidance behaviour can be of value in the treatment of patient populations with characteristics comparable to the current army study population (e.g., predominantly male, physically active, working, moderate but chronic back problems). Individuals at risk for poor long-term LBP recovery, i.e., individuals with high initial level of disability and prominent fear-avoidance behaviour, can be distinguished that may need additional cognitive-behavioural treatment.

Objective: To evaluate the effectiveness of specific lumbar extensor training compared with regular physical therapy (PT) in workers with nonspecific nonacute low back pain (LBP)., Design: A multicenter randomized controlled trial with 1-year follow-up., Setting: PT department in (military primary care) health centers., Participants: Predominantly male soldiers (N=129) with 4 weeks or more of low back complaints who were referred by the health center's general practitioner for PT (mean age, 35.9+/-10.8 y; range, 20-56 y), of whom 127 randomized participants were included in the analyses. One patient withdrew because of adverse effects during treatment., Interventions: Participants were assigned to 1 of 2 treatment programs: (1) a 10-week device-supported isolated lumbar extension training, twice a week, or (2) regular PT, mainly consisting of exercise therapy and aerobic activities., Main Outcome Measures: Functional status (Roland-Morris Disability Questionnaire, Patient-Specific Functional Scale) and global perceived effect were assessed in the short term (5 wk, 10 wk) and long term (6 mo, 12 mo)., Results: Both groups showed a favorable development in main outcomes over time: short-term improvements (after 10 weeks of treatment) remained stable or even slightly increased throughout the 12-month follow-up. No significant differences between the 2 groups were shown for any of the outcome measures, at any time., Conclusions: Consistent with prior evidence, specific back strengthening does not seem to offer incremental benefits in LBP management compared with regular PT care that mainly consists of general exercise therapy. (ISRCTN identifier ISRCTN19334317.)

Background: Researchers from the Royal Netherlands Army are studying the potential of isolated lumbar extensor training in low back pain in their working population. Currently, a randomized controlled trial is carried out in five military health centers in The Netherlands and Germany, in which a 10-week program of not more than 2 training sessions (10-15 minutes) per week is studied in soldiers with nonspecific low back pain for more than 4 weeks. The purpose of the study is to investigate the efficacy of this 'minimal intervention program', compared to usual care. Moreover, attempts are made to identify subgroups of different responders to the intervention., Methods: Besides a baseline measurement, follow-up data are gathered at two short-term intervals (5 and 10 weeks after randomization) and two long-term intervals (6 months and one year after the end of the intervention), respectively. At every test moment, participants fill out a compound questionnaire on a stand-alone PC, and they undergo an isometric back strength measurement on a lower back machine. Primary outcome measures in this study are: self-assessed degree of complaints and degree of handicap in daily activities due to back pain. In addition, our secondary measurements focus on: fear of movement/(re-) injury, mental and social health perception, individual back extension strength, and satisfaction of the patient with the treatment perceived. Finally, we assess a number of potential prognostic factors: demographic and job characteristics, overall health, the degree of physical activity, and the attitudes and beliefs of the physiotherapist towards chronic low back pain., Discussion: Although a substantial number of trials have been conducted that included lumbar extension training in low back pain patients, hardly any study has emphasized a minimal intervention approach comparable to ours. For reasons of time efficiency and patient preferences, this minimal sports medicine approach of low back pain management is interesting for the population under study, and possibly for comparable working populations with physical demanding job activities.

In a randomized, observer-blinded trial, the effectiveness of 3-month high-intensity training (HIT) of the isolated lumbar extensors was compared to low-intensity training (LIT). Eighty-one workers with nonspecific low back pain longer than 12 weeks were randomly assigned to either of the two training programs. Training sessions were performed on a modified training device that isolated the lower back extensors. Total intervention time was limited to 5-10 min (one or two training sessions) per week. Training effects were assessed in terms of changes in self-rated degree of back complaints, functional disability, and general, physical and mental health. Secondary outcomes in this study were muscle strength and fear of moving the back (kinesiophobia). Outcomes were evaluated at 1,2, 3, 6, and 9 months after randomization. The results showed that the two treatment programs led to comparable improvements in all outcome measures, except for mean isometric strength at 1, 2, 3, 6, and 9 months and kinesiophobia score at 2 and 9 months of follow-up. The high-intensity training group showed a higher strength gain (24 to 48 Nm) but a smaller decline in kinesiophobia (2.5 and 3.4 points, respectively), compared to the low-intensity training group. It can be concluded that high-intensity training of the isolated back extensors was not superior to a non-progressive, low-intensity variant in restoring back function in nonspecific (chronic) low back pain. In further research, emphasis should be put on identifying subgroups of patients that will have the highest success rate with either of these training approaches.