Classification of kneeling and squatting in workers wearing protective equipment: development and validation of a rule-based model using wireless triaxial accelerometers.

Several professions in industries, such as petroleum, manufacturing, construction, mining, and forestry require prolonged work tasks in awkward postures, increasing workers' risks for musculoskeletal pain and injury. Therefore, we developed and validated a rule-based model for classifying unilateral and bilateral kneeling and squatting based on 15 individuals wearing personal protective equipment and using three wireless triaxial accelerometers. The model provided both high sensitivity and specificity for classifying kneeling (0.98; 0.98) and squatting (0.96; 0.91). Hence, this model has the potential to contribute to increased knowledge of physical work demands and exposure thresholds in working populations with strict occupational safety regulations. Practitioner summary: Our results indicate that this rule-based model can be applied in a human-factors perspective enabling high-quality quantitative information in the classification of occupational kneeling and squatting, known risk factors for musculoskeletal pain, and sick leave. This study is adapted for working populations wearing personal protective equipment and aimed for long-term measurements in the workplace.

No Time to Lift? Designing Time-Efficient Training Programs for Strength and Hypertrophy: A Narrative Review.

Lack of time is among the more commonly reported barriers for abstention from exercise programs. The aim of this review was to determine how strength training can be most effectively carried out in a time-efficient manner by critically evaluating research on acute training variables, advanced training techniques, and the need for warm-up and stretching. When programming strength training for optimum time-efficiency we recommend prioritizing bilateral, multi-joint exercises that include full dynamic movements (i.e. both eccentric and concentric muscle actions), and to perform a minimum of one leg pressing exercise (e.g. squats), one upper-body pulling exercise (e.g. pull-up) and one upper-body pushing exercise (e.g. bench press). Exercises can be performed with machines and/or free weights based on training goals, availability, and personal preferences. Weekly training volume is more important than training frequency and we recommend performing a minimum of 4 weekly sets per muscle group using a 6-15 RM loading range (15-40 repetitions can be used if training is performed to volitional failure). Advanced training techniques, such as supersets, drop sets and rest-pause training roughly halves training time compared to traditional training, while maintaining training volume. However, these methods are probably better at inducing hypertrophy than muscular strength, and more research is needed on longitudinal training effects. Finally, we advise restricting the warm-up to exercise-specific warm-ups, and only prioritize stretching if the goal of training is to increase flexibility. This review shows how acute training variables can be manipulated, and how specific training techniques can be used to optimize the training response: time ratio in regard to improvements in strength and hypertrophy.

Return-to-work self-efficacy after occupational rehabilitation for musculoskeletal and common mental health disorders: Secondary outcomes of a randomized clinical trial.

OBJECTIVE: To assess the effects of adding a workplace intervention to inpatient occupational rehabilitation on return-to-work self-efficacy, and whether changes in return-to-work self-efficacy were associated with future work outcomes. DESIGN: Randomized clinical trial. SUBJECTS: Individuals aged 1860 years, sick-listed 212 months were randomized to multimodal inpatient rehabilitation with (n?=?88) or without (n?=?87) a workplace intervention. METHODS: Between-group differences for 4 months follow-up were assessed using linear mixed models. Associations between self-efficacy scores and future sickness absence days during 12 months of follow-up were assessed by linear regression. RESULTS: There were no statistically significant between-group differences in self-efficacy during follow-up. Participants with high or medium self-efficacy scores at the end of rehabilitation had fewer sickness absence days during follow-up compared with participants with low scores. Participants with consistently high scores or an increasing score throughout the programme showed fewer sickness absence days than those with reduced or consistently low scores. CONCLUSION: Receiving an added workplace intervention did not increase return-to-work self-efficacy more than standard inpatient occupational rehabilitation alone. High scores and a positive development in return-to-work self-efficacy were associated with higher work participation. This suggests that return-to-work self-efficacy could be an important factor to consider in the return-to-work process.

Periodized resistance training for persistent non-specific low back pain: a mixed methods feasibility study.

BACKGROUND: We investigated the feasibility of a 16-week supervised heavy resistance training program with weekly undulating periodization for individuals with persistent non-specific low-back pain (LBP). METHODS: Twenty-five adults with persistent non-specific LBP participated in this mixed methods feasibility study. Participants trained a whole-body program consisting of squat, bench press, deadlift and pendlay row two times per week for 16 weeks. We assessed pain intensity, pain-related disability, pain self-efficacy and one-repetition maximum strength at baseline, 8 weeks and 16 weeks. Three focus group interviews were conducted at the end of the program. Linear mixed models were used to assess changes in outcomes, and the qualitative data was assessed using systematic text condensation. RESULTS: We observed clinically meaningful reductions in pain intensity after 8 and 16 weeks of training. The mean difference on the numeric pain rating scale (0-10) in the last 2 weeks from baseline to 8 weeks was 2.6 (95% CI: 1.8-3.6) and from baseline to 16 weeks 3.4 (95% CI: 2.5-4.4). In addition, there were improvements in pain-related disability (3.9, 95% CI: 2.3-5.5), pain self-efficacy (7.7, 95% CI: 5.4-10.1) and muscle strength. In the focus group interviews, participants talked about challenges regarding technique, the importance of supervision and the advantages of periodizing the training. Perceived benefits were improved pain, daily functioning, energy level and sleep, and changes in views on physical activity. CONCLUSION: Periodized resistance training with weekly undulating periodization is a feasible training method for this group of individuals with persistent non-specific LBP. A randomized clinical trial should assess the efficacy of such an intervention. TRIAL REGISTRATION: clinicaltrials.gov / Identifier - NCT04284982, Registered on February 24th 2020.

Inpatient multimodal occupational rehabilitation reduces sickness absence among individuals with musculoskeletal and common mental health disorders: a randomized clinical trial.

Objectives This study aimed to investigate whether inpatient multimodal occupational rehabilitation (I-MORE) reduces sickness absence (SA) more than outpatient acceptance and commitment therapy (O-ACT) among individuals with musculoskeletal and mental health disorders. Methods Individuals on sick leave (2-12 months) due to musculoskeletal or common mental health disorders were randomized to I-MORE (N=86) or O-ACT (N=80). I-MORE lasted 3.5 weeks in which participants stayed at the rehabilitation center. I-MORE included ACT, physical exercise, work-related problem solving and creating a return to work plan. O-ACT consisted mainly of 6 weekly 2.5 hour group-ACT sessions. We assessed the primary outcome cumulative SA within 6 and 12 months with national registry-data. Secondary outcomes were time to sustainable return to work and self-reported health outcomes assessed by questionnaires. Results SA did not differ between the interventions at 6 months, but after one year individuals in I-MORE had 32 fewer SA days compared to O-ACT (median 85 [interquartile range 33-149] versus 117 [interquartile range 59-189)], P=0.034). The hazard ratio for sustainable return to work was 1.9 (95% confidence interval 1.2-3.0) in favor of I-MORE. There were no clinically meaningful between-group differences in self-reported health outcomes. Conclusions Among individuals on long-term SA due to musculoskeletal and common mental health disorders, a 3.5-week I-MORE program reduced SA compared with 6 weekly sessions of O-ACT in the year after inclusion. Studies with longer follow-up and economic evaluations should be performed.

Effectiveness of adding a workplace intervention to an inpatient multimodal occupational rehabilitation program: A randomized clinical trial.

Objectives This study aimed to evaluate the effectiveness of a workplace intervention (WI) added to an inpatient multimodal occupational rehabilitation program (I-MORE) on sickness absence. Methods In this researcher-blinded randomized controlled trial with parallel groups, individuals on sick leave due to musculoskeletal, unspecified- or common mental health disorders were randomized to I-MORE (N=87) or I-MORE+WI (N=88). I-MORE lasted 2+1 weeks (with one week at home in between) and consisted of "acceptance and commitment therapy", physical exercise, and work-related problem solving. The additional WI consisted of a preparatory part, a workplace meeting involving the sick-listed worker, the employer, and the primary rehabilitation therapist at the rehabilitation center, and follow-up work related to the meeting. The primary outcomes were number of sickness absence days and time until sustainable return to work (RTW) during 12 months of follow-up, measured by registry data. Results The median number of sickness absence days during the 12-month follow-up for I-MORE was 115 days [interquartile range (IQR) 53-183] versus 130 days (IQR 81-212) for I-MORE+WI. The difference between groups was not statistically significant (P=0.084). The hazard ratio for sustainable RTW was 0.74 (95% confidence interval 0.48-1.16; P=0.192) in favor of I-MORE. Conclusions This study provided no evidence in favor of I-MORE+WI compared to only I-MORE for long-term sickness absent individuals with musculoskeletal-, common mental- or unspecified disorders.

Electromyographic comparison of the barbell deadlift using constant versus variable resistance in healthy, trained men.

Variable, external resistance is proposed to increasingly augment the muscular stress throughout a dynamic movement. However, it is uncertain how different levels of variable resistance affect the activation in the deadlift. The aim of the study was to compare the electromyographic activity of the gluteus maximus, biceps femoris, semitendinosus, vastus lateralis and erector spinae muscles during the barbell deadlift with free weights (FW) alone, with two (FW-2EB), and four elastic bands (FW-4EB) to deload some of the constant external resistance. Fifteen resistance-trained men participated in a cross-over design where resistance loadings were matched using two-repetition maximum loadings in the three different conditions. For the whole movement, both repetitions were analyzed. For the phase-specific analysis, the last repetition was divided into six parts, i.e. the lower, middle and upper phase in both the ascending and descending phase of the movement. The mean deloading contributions from FW-2EB and FW-4EB were 21% and 41%, respectively. In FW-4EB, the erector spinae was activated more in the whole movement (8%, ES = 0.31, p = 0.002) compared to FW-2EB. There was also a tendency towards higher activation in FW-4EB versus FW for the whole movement (5%, ES = 0.18, p = 0.072). There were no significant differences between the conditions in any of the other phases or muscles (p = 0.106-0.926). In summary, a high contribution from variable, external resistance seems to activate the back extensors more than a low contribution.

The acceptance and commitment therapy model in occupational rehabilitation of musculoskeletal and common mental disorders: a qualitative focus group study.

Aims: The aim of this study was to examine whether and how intended processes of behavioural change were reflected in participants' experiences after an inpatient occupational rehabilitation programme. The programme was transdiagnostic, lasted 3½ weeks and was based on the acceptance and commitment therapy model.Methods: Twenty-two participants (17 women and 5 men) took part in five qualitative focus group interviews after the programme. Analysis was data-driven, categorising participants' experiences using an initial explorative phenomenological approach. The emerging data-driven categories were re-contextualised within the theoretical framework of the therapy model.Results: The participants referred to experiences within all three intended domains of the model (openness, awareness, and engagement). Our results indicate that the transdiagnostic approach may have facilitated openness, while the attainment of flexible self-awareness was less evident. Participants expressed engagement and behavioural changes linked to personal values, but did not mention actions leading to imminent return to work.Conclusions: The results imply that for implementation in occupational rehabilitation, further development of this model is needed specifically regarding processes related to self-awareness and committed action towards work. These findings are relevant for the interpretation of results from randomised clinical trials on acceptance and commitment therapy in occupational rehabilitation.Implications for rehabilitationAcceptance and commitment therapy seems to be a feasible component in an occupational rehabilitation programme for persons with different diagnoses.A transdiagnostic approach mixing musculoskeletal pain disorders and common mental disorders in the same rehabilitation programme seems to facilitate the process of openness and acceptance.There is a need to further develop and operationalise some of the processes in Acceptance and commitment therapy to accommodate the approach to the occupational rehabilitation context.

Unfolding the values of work - therapists´ experience of addressing the return to work process in occupational rehabilitation based on Acceptance and Commitment Therapy.

BACKGROUND: Facilitating return to work can be challenging due to the complexity of work disability. Few studies have examined rehabilitation programs based on Acceptance and Commitment Therapy that intend to support return to work, and none have investigated therapists' experience with providing such programs. The aim of this study was therefore to explore therapists' experience of addressing the return to work process in an inpatient occupational rehabilitation program based on Acceptance and Commitment Therapy. METHODS: This was a qualitative interview study supported by participant observation. Therapists were interviewed regarding their experiences with addressing return to work in an inpatient occupational rehabilitation program based on Acceptance and Commitment Therapy. In addition, the rehabilitation program was investigated through participant observation. The interviews were analysed according to Interpretative Phenomenological Analysis and informed by an analysis of field notes from the participant observation. RESULTS: Acceptance and Commitment Therapy was experienced as a meaningful approach to facilitate return to work, as it allowed therapists to address all relevant aspects of the individual participant's life that might influence work participation. The therapists' twofold goal was to support participants in building both a meaningful life and sustainable work participation. To do so, they attempted to instil long-term and interrelated processes concerning ownership, causes of sick leave, relation to expectations, the values of work, and the scope of agency. CONCLUSION: Unfolding values connected to work participation might reconcile the tension between work and family life by integrating work with other areas of life. Providing work participation with personal meaning also seems especially commensurable with a context where economy presents a poor incentive for return to work. Therapists should, however, be attentive to the need to secure the prominence of return to work by relating participants' chosen themes explicitly to their return to work process. Therapists should also be aware of the dilemma that may arise when they attempt to refrain from providing advice while simultaneously encouraging actions they consider appropriate to facilitate sustainable work participation. In addition, having an individual-oriented approach to occupational rehabilitation may obscure the extent to which return to work is a multi-stakeholder process.

Design of a study evaluating the effects, health economics, and stakeholder perspectives of a multi-component occupational rehabilitation program with an added workplace intervention - a study protocol.

BACKGROUND: Recent research has suggested that interventions at the workplace might be the most potent ingredient in return to work interventions, but few studies have investigated the different effects of workplace interventions as part of occupational rehabilitation programs. The comprehensive design described in this article includes effect (on return to work and health outcomes), and health economic evaluations of a workplace intervention added to a multicomponent rehabilitation program. Qualitative and mixed method studies will investigate sick-listed persons', rehabilitation therapists' and employers' perspectives on the usability and outcomes of the rehabilitation program and the workplace intervention. The program and intervention are provided to patients with musculoskeletal, psychological or general and unspecified diagnoses. The program is multi-component and includes Acceptance and Commitment Therapy, physical exercise, patient education and creating a plan for increased work participation. METHODS: Persons who are employed, aged from 18 to 60 years, with a current sick leave status of 50% or more and a diagnosis within the musculoskeletal, psychological or general and unspecified chapters of International Classification of Primary Care-2 (ICPC-2) will be recruited to a researcher-blinded parallel-group randomized controlled trial. All participants take part in an in-patient occupational rehabilitation program, while the intervention group also takes part in an intervention at the workplace. The effect and economic evaluation will investigate the effect of the added workplace intervention. The primary outcome measures will be time until full sustainable return to work and total number of sickness absence days in the 12 months after inclusion. Health economic evaluations will investigate the cost-effectiveness and cost-utility. Qualitative studies will investigate rehabilitation therapists' experiences with working towards return to work within an ACT-approach and stakeholders' experiences with the workplace intervention. A mixed methods study will combine quantitative and qualitative findings on the participants' expectations and motivation for return to work. DISCUSSION: The outline of this comprehensive study could represent an important addition to the standard designs of return to work evaluation. The mixed methods design, with qualitative approaches as well as a rigorous randomized controlled trial, might prove useful to shed light on contextual factors. TRIAL REGISTRATION: ClinicalTrials.gov : NCT02541890 . September 4, 2015.

Electromyographic Comparison of Barbell Deadlift, Hex Bar Deadlift, and Hip Thrust Exercises: A Cross-Over Study.

Andersen, V, Fimland, MS, Mo, D-A, Iversen, VM, Vederhus, T, Rockland Hellebø, LR, Nordaune, KI, and Saeterbakken, AH. Electromyographic comparison of barbell deadlift, hex bar deadlift, and hip thrust exercises: a cross-over study. J Strength Cond Res 32(3): 587-593, 2018-The aim of the study was to compare the muscle activation level of the gluteus maximus, biceps femoris, and erector spinae in the hip thrust, barbell deadlift, and hex bar deadlift; each of which are compound resisted hip extension exercises. After 2 familiarization sessions, 13 resistance-trained men performed a 1 repetition maximum in all 3 exercises in 1 session, in randomized and counterbalanced order. The whole ascending movement (concentric phase), as well as its lower and upper parts (whole movement divided in 2), were analyzed. The hip thrust induced greater activation of the gluteus maximus compared with the hex bar deadlift in the whole (16%, p = 0.025) and the upper part (26%, p = 0.015) of the movement. For the whole movement, the biceps femoris was more activated during barbell deadlift compared with both the hex bar deadlift (28%, p < 0.001) and hip thrust (20%, p = 0.005). In the lower part of the movement, the biceps femoris activation was, respectively, 48% and 26% higher for the barbell deadlift (p < 0.001) and hex bar deadlift (p = 0.049) compared with hip thrust. Biceps femoris activation in the upper part of the movement was 39% higher for the barbell deadlift compared with the hex bar deadlift (p = 0.001) and 34% higher for the hip thrust compared with the hex bar deadlift (p = 0.002). No differences were displayed for the erector spinae activation (p = 0.312-0.859). In conclusion, the barbell deadlift was clearly superior in activating the biceps femoris compared with the hex bar deadlift and hip thrust, whereas the hip thrust provided the highest gluteus maximus activation.

Nordic walking and specific strength training for neck- and shoulder pain in office workers: a pilot-study.

BACKGROUND: More than half of all adults have experienced neck pain during the last six months. Studies have demonstrated reduced pain in the neck-and shoulder region after specific strength training of the affected muscles, but specific endurance training of neck and shoulder muscles has not been properly examined. AIM: To examine the impact of Nordic walking (NW) compared to specific strength training (ST) and a non-training control group (Con) on self-reported neck-and shoulder pain among office workers. DESIGN: Randomized intervention trial with a stratified control group. SETTINGS: University research laboratory. POPULATION: Thirty-four female office workers with neck- and shoulder pain. METHODS: The participants were allocated to NW, ST or Con. Pain intensity (0-100 mm Visual Analog Scale), isometric abduction strength and a Six-Minute Walk Test (6MWT) were assessed pre, post and 10 weeks postintervention. Both training groups attended the training programs twice per week for ten weeks (30 minutes per session). RESULTS: Both training groups demonstrated a similar (P=0.421-0.802), but significant reduction in pain intensity (P=0.014-0.018). Between post-test and the 10 weeks postintervention test, similar pain intensity was observed in the NW (P=0.932) while the ST demonstrated an increase (P=0.136). Throughout the testing period, no difference in pain was observed for the Con (P=0.724-1.000) or between the Con and the training groups (P=0.421-0.802). No changes in strength and 6MWT were observed between or within the groups (P=0.184-0.870). CONCLUSIONS: Both NW and ST reduced pain for office workers with low neck-and shoulder pain and appear to be useful exercise modalities for this group. CLINICAL REHABILITATION IMPACT: Both interventions reduced pain, but larger randomized studies should verify these findings.

Multiple-joint exercises using elastic resistance bands vs. conventional resistance-training equipment: A cross-over study.

Previous studies indicate that elastic resistance bands (ERB) can be a viable option to conventional resistance-training equipment (CRE) during single-joint resistance exercises, but their efficacy has not been established for several commonly used multiple-joint resistance exercises. Thus, we compared muscular activation levels in four popular multiple-joint exercises performed with ERB (TheraBand®) vs. CRE (Olympic barbell or cable pulley machines). In a cross-over design, men and women (n = 29) performed squats, stiff-legged deadlifts, unilateral rows and lateral pulldown using both modalities. Multilevel mixed-effects linear regression analyses of main and interaction effects, and subsequent post hoc analyses were used to assess differences between the two resistance-training modalities. CRE induced higher levels of muscle activation in the prime movers during all exercises (p < .001 for all comparisons), compared to muscle activation levels induced by ERB. The magnitude of the differences was marginal in lateral pulldown and unilateral rows and for the erector spinae during stiff-legged deadlifts. In squats the quadriceps femoris activations were substantially lower for ERB. The differences between ERB and CRE were mostly observed during the parts of the contractions where the bands were relatively slack, whilst the differences were largely eliminated when the bands became elongated in the end ranges of the movements. We conclude that ERB can be a feasible training modality for lateral pulldowns, unilateral rows and to some extent stiff-legged deadlifts, but not for the squat exercise.

Core Muscle Activation in One-Armed and Two-Armed Kettlebell Swing.

The aim of the study was to compare the electromyographic activity of rectus abdominis, oblique external, and lower and upper erector spinae at both sides of the truncus in 1-armed and 2-armed kettlebell swing. Sixteen healthy men performed 10 repetitions of both exercises using a 16-kg kettlebell in randomized order. For the upper erector spinae, the activation of the contralateral side during 1-armed swing was 24% greater than that of the ipsilateral side during 1-armed swing (p < 0.001) and 11% greater during 2-armed swing (p = 0.026). Furthermore, the activation in 2-armed swing was 12-16% greater than for the ipsilateral side in 1-armed swing (p < 0.001). For rectus abdominis, however, 42% lower activation of the contralateral side was observed during 1-armed swing compared with ipsilateral sides during 2-armed swing (p = 0.038) and 48% compared with the ipsilateral side during 1-armed swing (p = 0.044). Comparing the different phases of the swing, most differences in the upper erector spinae were found in the lower parts of the movement, whereas for the rectus abdominis, the differences were found during the hip extension. In contrast, similar muscle activity in the lower erector spinae and external oblique between the different conditions was observed (p = 0.055-0.969). In conclusion, performing the kettlebell swing with 1 arm resulted in greater neuromuscular activity for the contralateral side of the upper erector spinae and ipsilateral side of the rectus abdominis, and lower activation of the opposite side of the respective muscles.

Sick-listed persons' experiences with taking part in an in-patient occupational rehabilitation program based on Acceptance and Commitment Therapy: a qualitative focus group interview study.

BACKGROUND: Occupational medicine has shifted emphasis from disease treatment to disability rehabilitation and management. Hence, newly developed occupational rehabilitation programs are often generic and multicomponent, aiming to influence the sick-listed persons' perception on return to work, and thereby support the return to work process. The aim of this study was to explore sick-listed persons' experiences with taking part in an in-patient occupational rehabilitation program based on Acceptance and Commitment Therapy. METHODS: Twenty-nine adults on sickness benefit or work assessment allowance due to musculoskeletal and/or common mental health disorders participated in this study. They were interviewed in focus groups at the beginning and at the end of a 3.5 week inpatient group-based occupational rehabilitation program in Central Norway. Key elements in the program were Acceptance and Commitment Therapy (ACT), physical exercise and creating a work-participation plan. The program was mainly group-based including participants with different diagnoses. Data was analyzed according to a phenomenological approach. RESULTS: At the start of the program most participants expressed frustration regarding being sick-listed, external anticipations as well as hindrances towards returning to work, and described hope that the program would provide them with the skills and techniques necessary to cope with health problems and being able to return to work. At the end of the program the participants described that they had embarked upon a long process of increased awareness. This process encompassed four areas; an increased awareness of what was important in life, realizing the strain from external expectations and demands, a need to balance different aspects of life, and return to work as part of a long and complex process. CONCLUSIONS: The occupational rehabilitation program induced a perceived meaningful reorientation encompassing several aspects of life. However, the return to work process was described as diffuse and uncertain for most participants. The providers of occupational rehabilitation program should balance this reorientation with specific steps towards return to work. Effect studies and long-term qualitative studies evaluating how this affects long-term work- and health outcomes are underway.

Elastic Bands in Combination With Free Weights in Strength Training: Neuromuscular Effects.

This study compared the effects of a variable vs. a constant lower limb resistance training program on muscle strength, muscle activation, and ballistic muscle performance at different knee angles. Thirty-two females were randomized to a constant resistance training free-weight group (FWG) or a variable resistance training group using free weights in combination with elastic bands (EBG). Two variations of the squat exercise (back squat and split) were performed 2 days per week for 10 weeks. Knee extensor maximal voluntary isometric contraction (MVC) and countermovement jump were assessed at knee angles of 60, 90, and 120° before and after the intervention. During the MVCs, muscle activation of the superficial knee extensor muscles was measured using surface electromyography. The FWG increased their MVCs at 60 and 90° (24 and 15%, respectively), whereas the EBG only increased significantly at 60° (15%). The FWG increased their jump height significantly at all angles (12-16%), whereas the EBG only improved significantly at 60 and 90° (15 and 10%, respectively). Both groups improved their 6-repetition maximum free-weight squat performance (EBG: 25% and FWG: 23%). There were no significant changes in muscle activation. In conclusion, constant and variable resistance training provided similar increases in dynamic and isometric strength, and ballistic muscle performance, albeit most consistently for the group training only with free weights.

Describing patients with a duration of sick leave over and under one year in Norway.

OBJECTIVE: This study aimed to describe the somatic, social, psychological, and work-related factors that characterize participants with a duration of sick leave over and under one year. METHODS: During 2012, 181 patients on long-term sick leave were consecutively recruited and asked to answer an extensive survey. Several outcomes were reported, addressing work-related factors and somatic, psychological, and social symptoms. In cross-sectional analyses, sick leave duration was dichotomized as > or < one year, based on Norwegian legislation. Linear and logistic regressions were used to estimate population probabilities and means. RESULTS: The estimated prevalence of pain, fatigue, anxiety, and depression was overall high. There was a tendency towards a higher prevalence of fatigue, anxiety, and depression in those with sick leave duration less than one year, with the exception of sleep problems, which was more frequent in the population with longer duration. Relationship with friends, family, co-workers, and the last workplace were worse in the population with longer duration. CONCLUSIONS: Cross-sectional analyses indicated that social and work-related problems are more adverse in patients with longer duration of sick leave, while psychological and somatic symptoms appear less adverse. This is one of the first studies quantitatively demonstrating these differences through comprehensive, simultaneously measured self-report questionnaires.

Effects of BOSU ball(s) during sit-ups with body weight and added resistance on core muscle activation.

The objective of this study was to assess the electromyographic activity of the rectus abdominis (upper and lower part) and external oblique during sit-ups performed on BOSU ball(s). Twenty-four men participated in a familiarization session, and in the next session, they performed the experimental tests in randomized order. The sit-ups were performed with 10 repetitions with body weight and with 10 repetition maximum (10RM) using elastic bands as external resistance under 4 different conditions: (a) on a stable surface, (b) with the BOSU ball under their feet (dome side down, lower-body instability), (c) BOSU ball under the low back (dome side up, upper-body instability), and (d) with BOSU balls under both feet and the low back (dual instability). The feet were not attached to the surface. We observed that with body weight, external oblique activation was decreased by upper-body instability and dual instability by 22-24% (p = 0.002-0.006), whereas the rectus abdominis was not affected by the surface. Using 10RM loads, the upper and lower rectus abdominis activities were increased by upper body and dual instability by 21-24% compared with that for a stable surface (P ≤ 0.001-0.036). Further, lower-body instability did not affect muscle activities significantly with either load for any condition. Hence, BOSU balls under the low back can increase and decrease abdominal muscle activation depending on the load, whereas placing a BOSU ball under the feet with the dome side down had little impact.

Effects of replacing free weights with elastic band resistance in squats on trunk muscle activation.

The purpose of this study was to assess the effects of adding elastic bands to free-weight squats on the neuromuscular activation of core muscles. Twenty-five resistance trained women with 4.6 ± 2.1 years of resistance training experience participated in the study. In randomized order, the participants performed 6 repetition maximum in free-weight squats, with and without elastic bands (i.e., matched relative intensity between exercises). During free-weight squats with elastic bands, some of the free weights were replaced with 2 elastic bands attached to the lowest part of the squat rack. Surface electromyography (EMG) activity was measured from the erector spinae, external oblique, and rectus abdominis, whereas a linear encoder measured the vertical displacement. The EMG activities were compared between the 2 lifting modalities for the whole repetition and separately for the eccentric, concentric, and upper and lower eccentric and concentric phases. In the upper (greatest stretch of the elastic band), middle, and lower positions in squats with elastic bands, the resistance values were approximately 117, 105, and 93% of the free weight-only trial. Similar EMG activities were observed for the 2 lifting modalities for the erector spinae (p = 0.112-0.782), external oblique (p = 0.225-0.977), and rectus abdominis (p = 0.315-0.729) in all analyzed phases. In conclusion, there were no effects on the muscle activity of trunk muscles of substituting some resistance from free weights with elastic bands in the free-weight squat.