Dynamic sitting may mitigate low back pain during prolonged seated work. The current study compared pelvis and lumbar spine kinematics, pain, and work productivity, in traditional and dynamic ...sitting. Sixteen participants completed three 20-min blocks of computer work and activity guided tasks in a traditional office chair or backless and multiaxial rotating seat pan while kinematics were measured from accelerometers on the low back. Pain ratings were recorded on a visual analogue scale every 10 min. Similar pelvis and lumbar kinematics emerged when performing computer work in traditional and dynamic sitting. Pelvis and lumbar sagittal and frontal plane shifts and fidgets were largest for dynamic sitting in the activity guided tasks. Buttocks pain was higher in dynamic sitting, but low back pain and work productivity were unaffected. Dynamic sitting increased spine movement during activity guided tasks, without negatively impacting lumbar kinematics, low back pain, or productivity during seated computer work.
•Lumbar kinematics were similar in office work for traditional and dynamic sitting.•Activity guided tasks increased lumbar spine movement.•Low back pain remained low throughout traditional and dynamic sitting.•Buttocks pain increased in dynamic sitting with no change in productivity.
To investigate the association between time to active sitting position and clinical features in people with COVID-19 admitted to intensive care unit (ICU) and referred to physiotherapists.
...Prospective study conducted in the largest temporary ICU in Lombardy (Italy) between April 2020 and June 2021. All individuals with COVID-19 who received physiotherapy were included. Multivariable Cox proportional hazard model was fitted to explore the statistical association between active sitting position and characteristics of patients referred to physiotherapists, also accounting for the different multidisciplinary teams responsible for patients.
284 individuals over 478 (59.4%) had access to physiotherapy, which was performed for a median of 8 days, without difference between multidisciplinary teams (P = 0.446). The active sitting position was reached after a median of 18 (IQR: 10.0–32.0) days. Sex was the only characteristic associated with the time to active sitting position, with males showing a reduced hazard by a factor of 0.65 (95% CI: 0.48–0.87; P = 0.0042) compared to females. At ICU discharge, nearly 50% individuals increased Manchester Mobility Score by 3 points. During physiotherapy no major adverse event was recorded.
Individuals with COVID-19 take long time to reach active sitting position in ICU, with males requiring longer rehabilitation than females.
•Individuals with COVID-19 require long time to reach active sitting position.•Sex gap in time to ASP may have clinically relevant impact on functional outcomes.•A structured physiotherapy team is the key to optimize early mobilization.
Standing desks and stability balls are increasingly popular to increase muscle activity and thereby prevent potential adverse cardiometabolic effects of prolonged sitting. The present study examined ...the effects of (1) sitting on a stability ball (‘active sitting’) and (2) hourly 10-min standing interruptions during prolonged sitting on postprandial cardiometabolic biomarkers.
Experimental crossover study.
Twenty healthy-weight males (19.2±0.6years) participated randomly in three 5-h conditions: (1) sitting on an office chair (SIT), (2) sitting on a stability ball (SIT-ACTIVE) and (3) sitting with hourly 10-min standing interruptions (SIT-STAND). In each condition, participants consumed a standardized mixed meal at baseline. Hourly blood samples and pre/post saliva samples were collected and analyzed for levels of insulin, glucose and cortisol. Pre/post hemodynamic monitoring (middle finger; Nexfin-monitoring) was conducted; heart rate was measured continuously (Polar) and muscle activity (leg and lower-back, Portilab) was measured during periods of sitting (on an office chair and on a stability ball) and standing.
Muscle activity and heart rate during standing periods were significantly higher than during sitting (both SIT and SIT-ACTIVE). Generalized estimating equations revealed no significant difference in any of the biomarkers between the three experimental conditions. Systolic blood pressure was lower during SIT-STAND, while stroke volume was lower during SIT-ACTIVE than during SIT. Although significant, these differences were small, approximating the day-to-day variability in blood pressure and stroke volume.
We conclude that hourly standing interruptions during 5h prolonged sitting or continuously sitting on a stability ball do not significantly affect postprandial cardiometabolic biomarkers in healthy young men.
Trial registration: This trial is registered in the NTR trial register (NTRcode 5723).
Prolonged sitting, common in many workplaces, reduces blood flow to the lower limb and has negative health outcomes. CoreChair is an active-sitting chair that encourages increased movement to help ...mitigate these outcomes. Physiological and cognitive measures were recorded in ten subjects over 4 h of sitting in both the CoreChair and a traditional office chair. Sitting in both chairs led to increases in calf circumference (p < 0.0001), reduced tactile sensitivity (p = 0.02), and a cognitive decline in attention (p = 0.035) over time. However, the increase in calf circumference was smaller in the CoreChair at the second (p = 0.017) and third hour (p = 0.012) compared to the traditional chair. Additionally, for the attention task, the traditional chair generated more attention-task errors (p = 0.005), while no changes were observed with the CoreChair (p = 0.13). These findings suggest that during prolonged sitting CoreChair may have modest physiological and cognitive benefits compared to a traditional chair.
•All measured physiological changes were affected by long duration sitting.•Increase in calf circumference, and therefore venous pooling was reduced with active sitting.•While foot sole skin sensitivity decreased across long duration sitting, it was not improved with the active chair.•Decreased attention over time of sitting was observed, which was partially mitigated by sitting in the active chair.
The potential physiological and psychological consequences of active sitting are not self-evident. The purpose of this study was to determine how active sitting affects hip motion, as well as domain ...specific cognitive function. Thirty-seven participants sat for 10 min in three different sitting conditions including a chair with a backrest, chair without a backrest, and an exercise ball. Hip acceleration was monitored using an ActiGraph GT9X Link triaxial accelerometer, and cognitive function was assessed using three different tasks including typing, reading comprehension, and spatial direction estimates. A significant difference in hip acceleration was found between participants that sat on the exercise ball compared to a stool. Additionally, the participants sitting on the ball attempted fewer total direction estimates and fewer egocentric-based direction estimates than the participants who sat on the stool. There may be little or no cognitive benefit to active sitting for many typical work tasks.
•Addressed limitations of measuring body movement during active sitting.•Accelerometers assess motion directly without dependence on body type and posture.•Band-pass filtering and novel metric design quantify small motion during sitting.•Moderate active sitting may convey limited cognitive benefits on some spatial tasks.•Active sitting showed no interaction with reading or typing performance.
Sedentary Behavior (SB), defined as sitting with minimal physical activity, is an emergent public health topic. However, the measurement of SB considers either posture (e.g., activPal) or physical ...activity (e.g., ActiGraph), and thus neglects either active sitting or inactive standing. The aim of this study was to determine the true amount of active sitting and inactive standing in daily life, and to analyze by how much these behaviors falsify the single sensors' sedentary estimates. Sedentary time of 100 office workers estimated with activPal and ActiGraph was therefore compared with Bland-Altman statistics to a combined sensor analysis, the posture and physical activity index (POPAI). POPAI classified each activPal sitting and standing event into inactive or active using the ActiGraph counts. Participants spent 45.0% 32.2%-59.1% of the waking hours inactive sitting (equal to SB), 13.7% 7.8%-21.6% active sitting, and 12.0% 5.7%-24.1% inactive standing (mean 5th-95th percentile). The activPal overestimated sedentary time by 30.3% 12.3%-48.4% and the ActiGraph by 22.5% 3.2%-41.8% (bias 95% limit-of-agreement). The results showed that sitting is not always inactive, and standing is not always active. Caution should therefore be paid when interpreting the activPal (ignoring active sitting) and ActiGraph (ignoring inactive standing) measured time as SB.
To determine the effects of a moderate-intensity active workstation on time and error during simulated office work.
The aim of the study was to analyse simultaneous work and exercise for ...non-sedentary office workers. We monitored oxygen uptake, heart rate, sweating stains area, self-perceived effort, typing test time with typing error count and cognitive performance during 30 min of exercise with no cycling or cycling at 40 and 80 W.
Compared baseline, we found increased physiological responses at 40 and 80 W, which corresponds to moderate physical activity (PA). Typing time significantly increased by 7.3% (p = 0.002) in C40W and also by 8.9% (p = 0.011) in C80W. Typing error count and cognitive performance were unchanged.
Although moderate intensity exercise performed on cycling workstation during simulated office tasks increases working task execution time with, it has moderate effect size; however, it does not increase the error rate. Participants confirmed that such a working design is suitable for achieving the minimum standards for daily PA during work hours.
•Pedalling workstation enables moderate exercise without seriously affecting work.•Half an hour daily usage achieves minimum physical activity recommendations.•Most participants would rather use this workstation than exercise outside work.•Can also be used during free time (sport events, TV, Cinema, PC, commuting, etc.).
Ergonomics science recommends office chairs that promote active sitting to reduce sitting related complaints. Since current office chairs do not fulfill this recommendation, a new chair was developed ...by inverting an existing dynamic chair principle. This study compares active sitting on the inverted chair during a simulated computer-based office task to two existing dynamic office chairs (n = 8). Upper body stability was analysed using Friedman ANOVA (p = .01). In addition, participants completed a questionnaire to rate their comfort and activity after half a working day. The inverted chair allowed the participants to perform a substantial range of lateral spine flexion (11.5°) with the most stable upper body posture (≤11 mm, ≤2°, p ≤ .01). The results of this study suggest that the inverted chair supports active sitting with backrest support during computer-based office work. However, according to comfort and activity ratings, results should be verified in a future field study with 24 participants. Practitioner Summary: This experimental laboratory study analyses the feasibility of active sitting with a backrest support during common office work on a new type of dynamic office chair. The results demonstrate that active sitting with a backrest support is feasible on the new but limited on existing chairs.
Sedentary Behavior (SB) is among the most frequent human behaviors and is associated with a plethora of serious chronic lifestyle diseases as well as premature death. Office workers in particular are ...at an increased risk due to their extensive amounts of occupational SB. However, we still lack an objective method to measure SB consistent with its definition. We have therefore developed a new measurement system based on muscular activity and accelerometry. The primary aim of the present study was to calibrate the new-developed 8-CH-EMG+ for measuring occupational SB against an indirect calorimeter during typical desk-based office work activities. In total, 25 volunteers performed nine office tasks at three typical workplaces. Minute-by-minute posture and activity classification was performed using subsequent decision trees developed with artificial intelligence data processing techniques. The 8-CH-EMG+ successfully identified all sitting episodes (AUC = 1.0). Furthermore, depending on the number of electromyography channels included, the device has a sensitivity of 83⁻98% and 74⁻98% to detect SB and active sitting (AUC = 0.85⁻0.91). The 8-CH-EMG+ advances the field of objective SB measurements by combining accelerometry with muscular activity. Future field studies should consider the use of EMG sensors to record SB in line with its definition.
We aimed to compare the hemodynamic responses to the active sitting test with the passive head-up tilt test (HUTT) in children and adolescents with postural tachycardia syndrome (POTS). We ...hypothesized that sitting tachycardia was also present in POTS patients during sitting.
We tested 30 POTS patients and 31 control subjects (mean age = 12 years, range = 9-16 years) who underwent both active sitting test and HUTT successively. We measured the heart rate (HR) and blood pressure (BP) during each test.
For both POTS patients and control subjects, the HUTT produced significantly larger HR and BP increases from 3 to 10 min of postural change than did the sitting test. Moreover, POTS patients with excessive orthostatic tachycardia during the HUTT also had significantly larger increases in HR at all test intervals during the sitting test than did the control subjects. A maximum increase in HR ≥ 22 bpm within 10 min of the sitting test was likely suggested to predict orthostatic tachycardia, yielding a sensitivity and specificity of 83.3 and 83.9%, respectively. Only six of 30 POTS patients (20%) reached the 40-bpm criterion during the sitting test, and no one complained of sitting intolerance symptoms.
We have shown that POTS patients also have sitting tachycardia when changing from a supine position to a sitting position. We believe that the active sitting test is a reasonable alternative maneuver in assessing POTS in population groups that cannot tolerate the standing test or HUTT.
PDF
