When Unnecessary Tasks Weigh Heavily on the Back: A Diary Study on Musculoskeletal Pain

Background: Auxiliary tasks such as administrative work often include tasks that are unnecessary in the view of workers but still have to be done. These tasks can threaten a worker's self-esteem. The purpose of this study was to examine the effects of unnecessary and unreasonable tasks on musculoskeletal pain. Methods: Fifty-five office workers (29 male; mean age = 41.96, SD = 14.2 years) reported their unnecessary and unreasonable tasks at the beginning of the study and kept a diary of their daily musculoskeletal pain over 5 weeks, using a visual analogue scale. Other work-related risk factors (prolonged sitting), job resources (participation in decision-making), and individual risk factors (sex, smoking, exercise, body mass index, maladaptive back beliefs) were controlled for in multilevel regression analysis. Findings: Multilevel regression analysis with 742 reports showed unnecessary tasks (B = 4.27, p = .006)-but not unreasonable tasks (B = 3.05, p = .074)-to predict the daily intensity of musculoskeletal pain, beyond other significant risk factors, such as prolonged sitting (B = 2.06, p = .039), body mass index (B = 1.52, p < .001), and maladaptive back beliefs (B = 3.78, p = .003). Participation in decision-making was not a significant protective factor (B = -1.67, p = .176). Conclusions/application to practice: The higher frequency of unnecessary tasks-compared with unreasonable tasks-could place workers at risk for musculoskeletal pain. Work redesign that reduces unnecessary and unreasonable tasks can make a valuable contribution to worker health and safety among office workers

Musculoskeletal and cognitive effects of stochastic resonance whole body vibration: a randomized controlled trial

Introduction: We investigated the acute musculoskeletal and cognitive effects of stochastic resonance whole-body vibration (SR-WBV). To our knowledge, no study looked at the effects of SR-WBV on inhibitory control so far. Materials and Methods: In this randomized controlled trial, participants were randomly allocated into a verum (6 Hz, SR-WBV) or sham (2 Hz, SR-WBV) condition. Inhibitory control was measured with the Stroop Test before and after the exercise. Also, muscle stiffness, muscle relaxation, sense of balance and surefootedness were assessed in a questionnaire before and after the exercise. Results: Inhibitory control increased significantly after verum SR-WBV (t = 2.949, P = 0.018), but not after sham SR-WBV (t = 1.165, P = 0.252). Muscle stiffness decreased significantly after verum (t = 5.273, P < 0.000), but not after sham SR-WBV (t = 1.533, P = 0.135). Also, muscle relaxation increased significantly after verum (t = -2.879, P = 0.007), but not after sham SR-WBV (t = -1.650, P = 0.108). Sense of balance increased significantly after verum (t = -2.061, P = 0.047), but not after sham SR-WBV (t = 0.347, P = 0.730). No significant effect was found in surefootedness, whether after verum (t = -0.966, P = 0.341) nor after sham SR-WBV (t = 0.849, P = 0.402). Conclusions: SR-WBV seems to be an appropriate method to improve not only physiological measurements but newly also cognition, i.e. inhibitory control. In this study we could show that SR-WBV exercise reduces interference and increases inhibitory control in a young and healthy sample. Keywords: Stochastic resonance whole body vibration (SRWBV); Musculoskeletal effects; Cognitive effects; Inhibitory control; Randomized controlled trial

Stochastic Resonance Training Improves Balance and Musculoskeletal Well-Being in Office Workers: A Controlled Preventive Intervention Study

Sixty-two office workers in a Swiss federal department were randomly assigned to a training and a control group. While the training group was instructed to complete 3 stochastic resonance whole-body vibration (SR-WBV) exercises every week for 4 weeks, the control group received no treatment. During this time all participants answered a daily questionnaire concerning their surefootedness, sense of balance, musculoskeletal well-being, and muscle relaxation. Before and after the 4-week SR-WBV intervention, balance was tested with a single-leg stance on a foam mat of the Balance Error Scoring System (BESS) using a SwayStar™-System measuring Total Angle Area (TotAngArea) and Total Velocity Area (TotVelArea). Multilevel results highlighted a significant increase over time for surefootedness and sense of balance (t = 2.491, p = .016), as well as for musculoskeletal well-being and muscle relaxation (t = 2.538, p = .014) in the training group but not in the control group. Balance tests showed improvement of balance in the training group (TotAngArea: Z = 2.550, p = .011; TotVelArea: Z = 3.334, p = .001) but not in the control group. SR-WBV exercise indicated a high compliance during this study (3.87±0.45 trainings per week) underlining its benefits for the working context. Especially office workers who spend most of their time in sitting position could profit from SR-WBV exercise to improve balance and reduce the risk of falls

Beyond physiology: Acute effects of side-alternating whole-body vibration on well-being, flexibility, balance, and cognition using a light and portable platform A randomized controlled trial.

A good body-balance helps to prevent slips, trips and falls. New body-balance interventions must be explored, because effective methods to implement daily training are sparse. The purpose of the current study was to investigate acute effects of side-alternating whole-body vibration (SS-WBV) training on musculoskeletal well-being, flexibility, body balance, and cognition. In this randomized controlled trial, participants were randomly allocated into a verum (8.5 Hz, SS-WBV, N = 28) or sham (6 Hz, SS-WBV, N = 27) condition. The training consisted of three SS-WBV series that lasted one-minute each with two one-minute breaks in between. During the SS-WBV series, participants stood in the middle of the platform with slightly bent knees. During the breaks in between, participants could loosen up. Flexibility (modified fingertip-to-floor method), balance (modified Star Excursion Balance Test), and cognitive interference (Stroop Color Word Test) were tested before and after the exercise. Also, musculoskeletal well-being, muscle relaxation, sense of flexibility, sense of balance, and surefootedness were assessed in a questionnaire before and after the exercise. Musculoskeletal well-being was significantly increased only after verum. Also, muscle relaxation was significantly higher only after verum. The Flexibility-Test showed significant improvement after both conditions. Accordingly, sense of flexibility was significantly increased after both conditions. The Balance-Test showed significant improvement after verum, and after sham. Accordingly, increased sense of balance was significant after both conditions. However, surefootedness was significantly higher only after verum. The Stroop-Test showed significant improvement only after verum. The current study shows that one SS-WBV training session increases musculoskeletal well-being, flexibility, body balance and cognition. The abundance of improvements on a light and portable platform has great influence on the practicability of training in daily life, aiming to prevent slip trips and falls at work

Acute effects of partial-body vibration in sitting position

AIM: To investigate the acute effects of sinusoidal and stochastic resonance partial-body vibration in sitting position, including muscle activity, heart rate variability, balance and flexibility. METHODS: Fifty healthy participants were assigned randomly to two training conditions: A sinusoidal partial-body vibration (SIN, 8 Hz) or a stochastic resonance partial-body vibration (STOCH, 8 ± 2 Hz). For baseline assessment participants sat on the vibration platform without vibration. Both training conditions consisted of five series of a one-minute vibration training and a one-minute break between them. In this experimental study surface electromyography (EMG) of the erector spinae (ES), one of the back muscles, and heart rate variability (HRV) was measured at baseline and during training. Balance and flexibility were assessed at baseline and immediately after training. Balance was measured with the modified star excursion balance test (mSEBT) and flexibility was assessed through the modified fingertip-to-floor method (mFTF). RESULTS: Paired sample t-test showed a significant increase in balance that was restricted to STOCH (t = -2.22, P = 0.018; SIN: t = -0.09, P = 0.466). An increase in flexibility was also restricted to STOCH (t = 2.65, P = 0.007; SIN: t = 1.41, P = 0.086). There was no significant change of muscle activity in the ES-EMG in STOCH or SIN conditions. In both training conditions, HRV decreased significantly, but remained in a low-load range (STOCH: t = 2.89, P = 0.004; SIN: t = 2.55, P = 0.009). CONCLUSION: In sitting position, stochastic resonance partial-body vibration can improve balance and flexibility while cardiovascular load is low. STOCH can be a valuable training option to people who are unable to stand (e.g., people, who are temporarily wheelchair-bound)