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Journal of Neurophysiology Aug 2019In addition to being a prerequisite for many activities of daily living, the ability to maintain steady upright standing is a relevant model to study sensorimotor... (Review)
Review
In addition to being a prerequisite for many activities of daily living, the ability to maintain steady upright standing is a relevant model to study sensorimotor integrative function. Upright standing requires managing multimodal sensory inputs to produce finely tuned motor output that can be adjusted to accommodate changes in standing conditions and environment. The sensory information used for postural control mainly arises from the vestibular system of the inner ear, vision, and proprioception. Proprioception (sense of body position and movement) encompasses signals from mechanoreceptors (proprioceptors) located in muscles, tendons, and joint capsules. There is general agreement that proprioception signals from leg muscles provide the primary source of information for postural control. This is because of their exquisite sensitivity to detect body sway during unperturbed upright standing that mainly results from variations in leg muscle length induced by rotations around the ankle joint. However, aging is associated with alterations of muscle spindles and their neural pathways, which induce a decrease in the sensitivity, acuity, and integration of the proprioceptive signal. These alterations promote changes in postural control that reduce its efficiency and thereby may have deleterious consequences for the functional independence of an individual. This narrative review provides an overview of how aging alters the proprioceptive signal from the legs and presents compelling evidence that these changes modify the neural control of upright standing.
Topics: Aging; Humans; Leg; Muscle Spindles; Postural Balance; Proprioception; Standing Position
PubMed: 31166819
DOI: 10.1152/jn.00067.2019 -
International Journal of Environmental... Nov 2021In Japan, standing while working has not yet become commonplace, and there is little evidence to support the benefits of standing during the workday. Therefore, this... (Randomized Controlled Trial)
Randomized Controlled Trial
In Japan, standing while working has not yet become commonplace, and there is little evidence to support the benefits of standing during the workday. Therefore, this study assessed the relationship between the introduction of a sit-stand desk and its ability to reduce the negative effects of sitting too long and increase employees' general health and productivity. Seventy-four Japanese desk workers participated in this three-month intervention study. Using a randomized controlled trial, the participants were divided into intervention ( = 36) and control ( = 38) groups. The participant characteristics were ascertained using a questionnaire. The intervention effectiveness was assessed by measuring health-, physical activity-, and work-related outcomes. The results indicate that the intervention group significantly decreased their sitting time at work ( = 0.002) and had reduced neck and shoulder pain ( = 0.001). There was a significant increase in subjective health ( = 0.002), vitality in work-related engagement ( < 0.001), and self-rated work performance over a four-week period ( = 0.017). These findings indicate a significant difference between the two groups, demonstrating the effectiveness of a sit-stand desk in reducing sedentary behavior and improving workers' health and productivity. Future research can accumulate further evidence of best practice use of sit-stand desks.
Topics: Efficiency; Humans; Occupational Health; Sedentary Behavior; Standing Position; Workplace
PubMed: 34770116
DOI: 10.3390/ijerph182111604 -
The Journal of Spinal Cord Medicine May 2018Impaired balance function after a spinal cord injury (SCI) hinders performance of daily activities.
CONTEXT
Impaired balance function after a spinal cord injury (SCI) hinders performance of daily activities.
OBJECTIVE
To assess the evidence on the effectiveness of task-specific training on sitting and standing function in individuals with SCI across the continuum of care.
METHODS
A systematic search was conducted on literature published to June 2016 using people (acute or chronic SCI), task-specific interventions compared to conventional physical therapy, and outcome (sitting or standing balance function). The PEDro scale was used to investigate the susceptibility to bias and trial quality of the randomized controlled trials (RCTs). A standardized mean difference (SMD) was conducted to investigate the effect size for interventions with sitting or standing balance outcomes.
RESULTS
Nineteen articles were identified; three RCTs, two prospective controlled trials, one cross-over study, nine pre-post studies and four prospective cohort studies. RCT and cross-over studies were rated from 6 to 8 indicating good quality on the PEDro scale. The SMD of task-specific interventions in sitting compared to active and inactive (no training) control groups was -0.09 (95% CI: -0.663 to 0.488) and 0.39 (95% CI: -0.165 to 0.937) respectively, indicating that the addition of task-specific exercises did not affect sit and reach test performance significantly. Similarly, the addition of BWS training did not significantly affect BBS compared to conventional physical therapy -0.36 (95% CI: -0.840 to 0.113). Task-specific interventions reported in uncontrolled trials revealed positive effects on sitting and standing balance function.
CONCLUSION
Few RCT studies provided balance outcomes, and those that were evaluated indicate negligible effect sizes. Given the importance of balance control underpinning all aspects of daily activities, there is a need for further research to evaluate specific features of training interventions to improve both sitting and standing balance function in SCI.
Topics: Adult; Clinical Trials as Topic; Exercise Therapy; Female; Humans; Male; Middle Aged; Neurological Rehabilitation; Postural Balance; Sitting Position; Spinal Cord Injuries; Standing Position
PubMed: 28738740
DOI: 10.1080/10790268.2017.1350340 -
Journal of the American Veterinary... Aug 2022
Topics: Animals; Standing Position
PubMed: 36006911
DOI: 10.2460/javma.260.12.1406 -
Physical Therapy in Sport : Official... May 2021We aimed to assess the test-retest reliability of a supine and standing knee joint position sense (JPS) test, respectively, and whether they discriminate knees with...
OBJECTIVES
We aimed to assess the test-retest reliability of a supine and standing knee joint position sense (JPS) test, respectively, and whether they discriminate knees with anterior cruciate ligament (ACL) injury from asymptomatic knees.
DESIGN
Repeated measures and cross-sectional.
SETTING
Research laboratory.
PARTICIPANTS
For test-retest reliability, 24 persons with asymptomatic knees. For discriminative analysis: 1) ACLR - 18 persons on average 23 months after unilateral ACL reconstruction, 2) CTRL - 23 less-active persons, and 3) ATHL - 21 activity level-matched athletes.
MAIN OUTCOME MEASURES
Absolute error (AE) and variable error (VE).
RESULTS
Test-retest reliability was generally highest for AE of the standing test (ICC 0.64-0.91). Errors were less for the standing compared to the supine test across groups. CTRL had greater knee JPS AE (P = 0.005) and VE (P = 0.040) than ACLR. ACLR knees showed greater VE compared to the contralateral non-injured knees for both tests (P = 0.032), albeit with a small effect size (η = 0.244).
CONCLUSIONS
Our standing test was more reliable and elicited lesser errors than our supine test. Less-active controls, rather than ACLR, produced significantly greater errors. Activity level may be a more predominant factor than ACLR for knee JPS ∼2 years post-reconstruction.
Topics: Adult; Anterior Cruciate Ligament Injuries; Anterior Cruciate Ligament Reconstruction; Cross-Sectional Studies; Female; Humans; Knee Joint; Male; Proprioception; Range of Motion, Articular; Reproducibility of Results; Standing Position; Supine Position; Young Adult
PubMed: 33667776
DOI: 10.1016/j.ptsp.2021.02.010 -
International Journal of Environmental... May 2021The aim of the study was to compare the static balance of dancers and non-dancers in a bipedal and unipedal stance. Twenty-three female dancers (mean age: 21.3 ± 1.7)...
The aim of the study was to compare the static balance of dancers and non-dancers in a bipedal and unipedal stance. Twenty-three female dancers (mean age: 21.3 ± 1.7) and 24 age and sex-matched subjects (mean age 22.3 ± 1.0) participated in this study. A force platform was used to assess balance. The tests on the balance platform were performed in several positions with different foot placement, such as normal standing (NS) eyes open and eyes closed positions, semi-tandem position (ST), tandem position (TP), and one-leg standing (1L) eyes open and eyes closed position. Significant differences in balance between the dancers and the control group, especially in the tandem position and one-leg standing position with eyes closed were found. We observed higher results for the velocity of the COP in the frontal plane in the TP with a dominant limb in front ( = 0.04) and higher results for the velocity of the COP in the frontal plane ( = 0.01) and in the sagittal plane ( < 0.01) in the TP with a dominant limb in front in the control group. We also observed significant differences between groups in the mean velocity of COP sway in the sagittal plane in the 1 L position with eyes closed ( = 0.04). We concluded that dancing regularly for several years improves static balance.
Topics: Adult; Dancing; Eye; Female; Foot; Humans; Postural Balance; Standing Position; Young Adult
PubMed: 34064678
DOI: 10.3390/ijerph18105056 -
PloS One 2023According to research on the effects of posture on psychological states, high-power poses-with the body spread wide open-lead to high-arousal positive emotions, whereas...
According to research on the effects of posture on psychological states, high-power poses-with the body spread wide open-lead to high-arousal positive emotions, whereas low-power poses-with the body slumped and constricted-lead to low-arousal negative emotions. However, postures that lead to both high-arousal negative and low-arousal positive emotions have not been investigated yet. Although relative comparisons between postures have been made, the positioning of postures on the two-dimensional coordinates created by arousal and valence has not been clarified. Therefore, the purpose of this study was to explore and clarify which postures lead to the four types of emotions: high-arousal negative, high-arousal positive, low-arousal negative, and low-arousal positive. In Experiment 1, 29 participants (13 men and 16 women) adopted 12 sitting postures for 1 minute each. In Experiment 2, 25 participants (13 men and 12 women) adopted six sitting and six standing postures for 1 minute each. Arousal and valence were measured after each posture, and heart rate was measured during posture maintenance. Arousal and valence after adopting the postures were compared with the neutral arousal and valence. As a result, postures leading to high-arousal negative and low-arousal positive emotions were identified. In addition, postures leading to high-arousal positive emotions, which are the high-power poses, were identified. There were no differences in the magnitude of psychological effects between sitting and standing postures.
Topics: Male; Humans; Female; Sitting Position; Emotions; Posture; Standing Position; Arousal
PubMed: 37267405
DOI: 10.1371/journal.pone.0286720 -
Journal of Neuroengineering and... Nov 2022In older adults, the extent to which performing a cognitive task when standing diminishes postural control is predictive of future falls and cognitive decline. The...
BACKGROUND
In older adults, the extent to which performing a cognitive task when standing diminishes postural control is predictive of future falls and cognitive decline. The neurophysiology of such "dual-tasking" and its effect on postural control (i.e., dual-task cost) in older adults are poorly understood. The purpose of this study was to use electroencephalography (EEG) to examine the effects of dual-tasking when standing on brain activity in older adults. We hypothesized that compared to single-task "quiet" standing, dual-task standing would decrease alpha power, which has been linked to decreased motor inhibition, as well as increase the ratio of theta to beta power, which has been linked to increased attentional control.
METHODS
Thirty older adults without overt disease completed four separate visits. Postural sway together with EEG (32-channels) were recorded during trials of standing with and without a concurrent verbalized serial subtraction dual-task. Postural control was measured by average sway area, velocity, and path length. EEG metrics included absolute alpha-, theta-, and beta-band powers as well as theta/beta power ratio, within six demarcated regions-of-interest: the left and right anterior, central, and posterior regions of the brain.
RESULTS
Most EEG metrics demonstrated moderate-to-high between-day test-retest reliability (intra-class correlation coefficients > 0.70). Compared with quiet standing, dual-tasking decreased alpha-band power particularly in the central regions bilaterally (p = 0.002) and increased theta/beta power ratio in the anterior regions bilaterally (p < 0.001). A greater increase in theta/beta ratio from quiet standing to dual-tasking in numerous demarcated brain regions correlated with greater dual-task cost (i.e., absolute increase, indicative of worse performance) to postural sway metrics (r = 0.45-0.56, p < 0.01). Lastly, participants who exhibited greater alpha power during dual-tasking in the anterior-right (r = 0.52, p < 0.01) and central-right (r = 0.48, p < 0.01) regions had greater postural sway velocity during dual-tasking.
CONCLUSION
In healthy older adults, alpha power and theta/beta power ratio change with dual-task standing. The change in theta/beta power ratio in particular may be related to the ability to regulate standing postural control when simultaneously performing unrelated, attention-demanding cognitive tasks. Modulation of brain oscillatory activity might therefore be a novel target to minimize dual-task cost in older adults.
Topics: Humans; Aged; Reproducibility of Results; Postural Balance; Attention; Standing Position; Brain; Cognition
PubMed: 36369027
DOI: 10.1186/s12984-022-01095-3 -
Orthopadie (Heidelberg, Germany) Dec 2022The spinal shape and the pelvic ante-/retroversion of an individual are determined by its innate, genetically fixed lumbosacral angulation. This can be measured with... (Review)
Review
The spinal shape and the pelvic ante-/retroversion of an individual are determined by its innate, genetically fixed lumbosacral angulation. This can be measured with little effort in the lateral standing radiograph of the patient. In spinal surgery, there are a lot of original papers on the topic. In hip surgery, however, the individual pelvic version and its consequences for the acetabular orientation have not received the same attention so far.This review focuses on previous data on the relationship between lumbosacral angulation and pelvic ante-/retroversion. Four anatomically definable pelvic types can be distinguished; three of those have to be considered as facultatively pathogenetic. Clinical consequences arise for the clinical pictures of spondylolisthesis, non-specific lower back pain, acetabular retroversion and developmental dysplasia of the hip, as well as for acetabular cup positioning in total hip arthroplasty.
Topics: Humans; Acetabulum; Arthroplasty, Replacement, Hip; Pelvis; Radiography; Standing Position
PubMed: 36222867
DOI: 10.1007/s00132-022-04321-x -
Physical Therapy Feb 2021The objectives of this study were to describe sitting, standing, and stepping patterns for people with lower limb amputation (LLA) and to compare sitting, standing, and... (Comparative Study)
Comparative Study
OBJECTIVE
The objectives of this study were to describe sitting, standing, and stepping patterns for people with lower limb amputation (LLA) and to compare sitting, standing, and stepping between people with dysvascular LLA and people with traumatic LLA.
METHODS
Participants with dysvascular or traumatic LLA were included if their most recent LLA was at least 1 year earlier, they were ambulating independently with a prosthesis, and they were between 45 and 88 years old. Sitting, standing, and stepping were measured using accelerometry. Daily sitting, standing, and stepping times were expressed as percentages of waking time. Time spent in bouts of specified durations of sitting (<30, 30-60, 60-90, and >90 minutes), standing (0-1, 1-5, and >5 minutes), and stepping (0-1, 1-5, and >5 minutes) was also calculated.
RESULTS
Participants (N = 32; mean age = 62.6 [SD = 7.8] years; 84% men; 53% with dysvascular LLA) spent most of the day sitting (median = 77% [quartile 1 {Q1}-quartile 3 {Q3} = 67%-84%]), followed by standing (median = 16% [Q1-Q3 = 12%-27%]) and stepping (median = 6% [Q1-Q3 = 4%-9%]). One-quarter (median = 25% [Q1-Q3 = 16%-38%]) of sitting was accumulated in bouts of >90 minutes, and most standing and stepping was accrued in bouts of <1 minute (standing: median = 42% [Q1-Q3 = 34%-54%]; stepping: median = 98% [Q1-Q3 = 95%-99%]). Between-etiology differences included proportion of time sitting (traumatic: median = 70% [Q1-Q3 = 59%-78%]; dysvascular: median = 79% [Q1-Q3 = 73%-86%]) and standing (traumatic: median = 23% [Q1-Q3 = 16%-32%]; dysvascular: median = 15% [Q1-Q3 = 11%-20%]).
CONCLUSION
Participants had high daily volumes of long durations of sitting. Further, these individuals accumulated most physical activity in bouts of <1 minute.
IMPACT
High levels of sedentary behavior and physical inactivity patterns may place people with LLA at greater mortality risk relative to the general population. Interventions to minimize sedentary behaviors and increase physical activity are potential strategies for improving poor outcomes of physical therapy after LLA.
Topics: Accelerometry; Aged; Aged, 80 and over; Amputees; Artificial Limbs; Cross-Sectional Studies; Disability Evaluation; Exercise; Female; Humans; Lower Extremity; Male; Middle Aged; Sitting Position; Standing Position; Time Factors; Walking
PubMed: 33336706
DOI: 10.1093/ptj/pzaa212