Five-Repetition Sit-to-Stand Test as Predictor of Mortality in High Risk COPD Patients.

OBJECTIVE: To determine if adding performance on the five-repetition sit-to-stand test (5-STS) to chronic obstructive pulmonary disease (COPD) high-risk criteria, proposed by the Spanish COPD guidelines (GesEPOC), affects mortality prognosis. METHODS: Observational study of COPD outpatients involved prospective follow-up for 5 years. Patients were classified based on 5-STS performance and risk criteria proposed by GesEPOC version 2021. Outcome measures were 5-year mortality timing and rate. Kaplan-Meier curves and univariate and multivariate Cox proportional-hazard analyses, analysis of variance, and univariate and multivariate linear and logistic regression models were used. RESULTS: One hundred and thirty-seven patients were included. Mean age was 66±8.3 years, and 87.6% were men. Of them, 115 (83.9%) were classified as high risk, 43 (34.4%) of whom had poor performance on the 5-STS. Overall mortality at 5 years was 27% and was significantly higher in the high-risk (29.6%) compared with the low-risk (13.6%) group. Among high-risk patients, mortality at 5 years was significantly worse with poor 5-STS performance (60.5%) compared with non-poor performance (11.1%). Poor performance on the 5-STS was independently associated with increased 5-year mortality risk (HR 4.70; 95% CI: 1.96-11.27) in a model adjusted for history of heart disease and dyspnea. CONCLUSION: Among high-risk COPD patients, those with poor performance on the 5-STS have a significantly higher mortality at 5 years than those with non-poor 5-STS performance.

The effect of visual cues at different heights on sit-to-stand movements in people with and without low back pain.

BACKGROUND: Investigating movement strategies that can be utilized to avoid pain-provocation could enhance the management of low back pain episodes. OBJECTIVE: To assess the effect of visual cues at different heights on the kinematics of sit-to-stand movements, as well as perceived difficulty and pain levels. DESIGN: Cross-over design comparing individuals with low back pain to healthy controls. METHODS: 26 asymptomatic controls and 15 individuals with chronic, recurrent low back pain performed 5 sets of 5 sit-to-stand movements. High, middle, and low visual cues were used during sets 2-4. Spinal sagittal plane range of motion, peak spinal flexion and extension angles, and trunk centre of mass velocity were obtained from kinematic data. RESULTS: The low cue led to significantly more head and lumbar spine flexion, while the high cue led to significantly more head and thoracic spine extension and increased thoracic spine range of motion. The low back pain group demonstrated a significantly lower vertical trunk centre of mass velocity than the control group during the high cue trials. There was a significant association between higher perceived difficulty scores and lower trunk centre of mass velocity for the low back pain group. Pain scores were not significantly different between cue conditions. CONCLUSION: Visual cues can be used to temporarily change the spinal kinematics of sit-to-stand movements in people with and without low back pain. This could be helpful in clinical practice to encourage more, or less, movement in specific spinal regions, and avoid pain provocation to facilitate functional rehabilitation.

Dynamics of sit-to-stand and stand-to-sit motions based on the trajectory control of the centre of mass of the body: A bond graph approach.

This paper presents a bond graph model for the dynamics of sit-to-stand (SiTSt) and stand-to-sit (StTSi) motions. It is hypothesized that, for these motions, the central nervous system (CNS) controls the trajectory of the centre of mass of the body (COMB). The model comprises two identical submodels: one submodel emulates the working of the CNS, and the other represents the human body. Reference trajectories of the COMB determined through experimentation are input to the submodel representing the working of CNS, which automatically determines the required joint angle trajectories. Based on the required and actual joint angle trajectories, proportional integral derivative controllers at the joints (j-PID) provide the required joint torques to actuate the human body submodel. Simulation results show that during SiTSt or StTSi motions, the centre of mass of the human body submodel follows the commanded trajectories. The joint angle trajectories from the submodel representing the working of CNS closely follow the respective experimental joint angle trajectories. Also, for each motion, joint angles, torques and powers are presented, which agree with earlier studies. These findings provide adequate confidence in proposed hypothesis and indicate the potential of developed model for other biomechanical investigations of SiTSt and StTSi motions.

The Impact of COVID-19 on Functional Capacity and Pulmonary Outcomes in the Hail Region: A Cross-Sectional Study.

Background/Objectives: COVID-19, caused by the novel coronavirus SARS-CoV-2, has had a significant impact on life worldwide since its emergence in late 2019. The virus has caused a global pandemic, leading to widespread health, social, economic, and psychological effects. COVID-19 mainly affects the respiratory system. This study aimed to compare the functional capacity and pulmonary function outcomes between COVID-19 patients and individuals who have not been infected in the Hail region. Methods: Individuals of both genders above 18 years old who had been infected with COVID-19 in the previous 6 months or had never been infected were eligible to participate. Local hospitals and social media apps were used to recruit willing participants. Heart rate, pulse oxygen saturation, blood pressure, pulmonary function test, hand grip strength, and functional tests (6 min walk test, 30 s sit-to-stand test, and timed up and go test) were measured and compared between the groups. Statistical analysis was performed using SPSS Version 25. Results: Forty individuals affected with COVID-19 and forty-one healthy individuals were recruited. Our results showed that in individuals affected with COVID-19, scores on the minute ventilation, 30 s sit-to-stand, and 6 min walk tests were significantly lower than among healthy individuals. Other outcomes did not show any statistical differences between the groups. Conclusion: This study contributes to a greater understanding of the functional capacity status of individuals with COVID-19. Patients affected by COVID-19 may develop an impaired lung capacity and a decreased function capacity. These factors may negatively affect physical and cognitive health status. Future studies should evaluate the benefits of interventions with rehabilitation exercises following COVID-19. In light of the functional capacity and pulmonary function decline in individuals affected by COVID-19, interventions encompassing pulmonary and functional rehabilitation exercises are recommended to improve physical fitness and pulmonary function post-COVID-19.

Accuracy Validation of a Sensor-Based Inertial Measurement Unit and Motion Capture System for Assessment of Lower Limb Muscle Strength in Older Adults-A Novel and Convenient Measurement Approach.

(1) Background: The aim of this study was to assess lower limb muscle strength in older adults during the transfer from sitting to standing (STS) using an inertial measurement unit (IMU). Muscle weakness in this population can severely impact function and independence in daily living and increase the risk of falls. By using an IMU, we quantified lower limb joint moments in the STS test to support health management and individualized rehabilitation program development for older adults. (2) Methods: This study involved 28 healthy older adults (13 males and 15 females) aged 60-70 years. The lower limb joint angles and moments estimated using the IMU were compared with a motion capture system (Mocap) (pair t-test, ICC, Spearman correlations, Bland-Altman plots) to verify the accuracy of the IMU in estimating lower limb muscle strength in the elderly. (3) Results: There was no significant difference in the lower limb joint angles and moments calculated by the two systems. Joint angles and moments were not significantly different (p > 0.05), and the accuracy and consistency of the IMU system was comparable to that of the Mocap system. For the hip, knee, and ankle joints, the ICCs for joint angles were 0.990, 0.989, and 0.885, and the ICCs for joint moments were 0.94, 0.92, and 0.89, respectively. In addition, the results of the two systems were highly correlated with each other: the r-values for hip, knee, and ankle joint angles were 0.99, 0.99, and 0.96, and the r-values for joint moments were 0.92, 0.96, and 0.85. In the present study, there was no significant difference (p > 0.05) between the IMU system and the Mocap system in calculating lower limb joint angles and moments. (4) Conclusions: This study confirms the accuracy of the IMU in assessing lower limb muscle strength in the elderly. It provides a portable and accurate alternative for the assessment of lower limb muscle strength in the elderly.

Differences in power and performance during sit-to-stand test and its relationships to functional measures in older adults with and without Parkinson's disease.

AIMS: i) to compare 30-s sit-to-stand (STS) test repetitions and power between older adults with and without Parkinson's disease (PD) and ii) to evaluate the relationship of STS repetitions and power with functional measures in older people with PD. METHODS: STS repetitions and power (Alcazar's equation) during the 30-s STS test were assessed in forty-six age- and sex-matched older adults with and without PD. Functional measures included habitual (HGS) and maximum gait speed (MGS), timed-up-and-go (TUG) test and the Mini-Balance Evaluation System Test (Mini-BEST). PD-specific tests were as follows: the motor subscale of the Unified Parkinson's Disease Rating Scale (UPDRS-III), quality of life [Parkinson's Disease Questionnaire (PDQ-39)], perceived freezing of gait (FOG questionnaire), and fear of falling [Falls Efficacy Scale (FES)]. T scores, repeated measures ANOVA and linear regression analyses were used. RESULTS: T scores for older adults with PD were - 2.7 ± 4.5 for STS repetitions, -5.2 ± 4.2 for absolute STS power, and - 3.1 ± 4.6 for relative STS power compared to older adults without PD. T scores for absolute STS power were lower than T scores for STS repetitions (p < 0.001) and relative STS power (p < 0.001). Both absolute and relative STS power and STS repetitions showed similar correlations with functional measures (r = 0.44 to 0.59; both p < 0.05). Relative STS power (r = -0.55; p < 0.05) and STS repetitions (r = -0.47 to -0.55; p < 0.05) but not absolute STS power were correlated to PD-specific tests. CONCLUSIONS: STS repetitions and power values estimated through the 30-s STS test were lower in older people with PD than without PD. Overall, STS power measures were similarly associated with functional performance as STS repetitions, indicating these power equations can be implemented when assessing lower extremity function in older people with PD.

Teleassessment using five times sit-to-stand test in older adults with and without Parkinson's disease: Guidelines and barriers.

BACKGROUND AND PURPOSE: Assessing lower limb strength, balance, and fall risk are crucial components of rehabilitation, especially for the older adult population. With the growing interest in telehealth, teleassessment has been investigated as an alternative when in-person assessments are not possible. The Five Times Sit-to-Stand test (5TSTS) provides a quick measure of balance during chair transfers, muscle power, endurance, and the hability to change and maintain body position, and is highly recommended by guidelines. However, the literature is unclear about the viability and safety of teleassessment using the 5TSTS in older adults with and without Parkinson's disease (PD). This study aimed to evaluate the reliability of teleassessment using the 5TSTS and to determine its feasibility and safety for older adults with and without PD. METHODS: This cross-sectional study included older adults with and without PD who were evaluated remotely through a videoconference platform. To ensure effective and comprehensive instructions for the test, we developed a guideline called OMPEPE (an acronym for: Objective; Materials; Position-Start; Execution; Position-End; Environment). We assessed the 5TSTS intra- and inter-rater reliability by comparing scores obtained from the same examiner and from different examiners, respectively. Participants and examiners completed online surveys to provide information about feasibility and safety. RESULTS: Twelve older adults with PD and 17 older adults without PD were included in this study (mean ages 69.0 and 67.6 years, respectively). Based on the participants' perspectives and the absence of adverse effects, teleassessment using the 5TSTS is feasible and safe for older adults with and without PD. Excellent intra- and inter-rater reliability (intraclass correlation coefficient >0.90) was found for all measurements of the 5TSTS. DISCUSSION: This study demonstrated the feasibility, safety, and reliability of teleassessment using the 5TSTS. The guidelines developed may help health professionals minimize barriers and safely conduct an online assessment that includes a physical test such as the 5TSTS in older adults with or without PD. In addition to addressing technological barriers, the OMPEPE guideline might ensure the optimal execution of evaluations. CONCLUSION: Teleassessment using the 5TSTS for older adults with and without PD is feasible and safe. Both synchronous (i.e., live) and asynchronous (i.e., recorded) online 5TSTS tests demonstrate excellent intra- and inter-rate reliability.

Effect of coaching the sit-to-stand motion and attentional focus.

[Purpose] The present study investigated whether (1) "standing up while bowing" is effective for promoting the sit-to-stand (STS) motion and (2) whether this coaching promotes internal focus. [Participants and Methods] The participants included 17 healthy adults who performed the 30-s chair stand test with two sets of verbal instructions. The verbal instructions were as follows: "Please stand up as many times as possible for 30 s" (control condition) and "Please stand up while bowing as many times as possible for 30 s" (bowing condition). The participants performed the tests successively under the two conditions. In the 30-s chair stand test, a three-axis accelerometer was attached to the participants and the sagittal STS motion was filmed using a video camera. After the 30-s chair stand test, we used the modified Movement-Specific Reinvestment Scale (MSRS) to evaluate attentional focus. Differences in the measurements were analyzed using the Wilcoxon signed-rank test or paired t-test for each condition. [Results] Statistical analysis revealed significant differences in the CS-30 count, time from sitting to standing, time from sitting to lift-off, time from lift-off to standing, and the trunk tilt angle on lift-off. Regarding the questionnaire, Statistical analysis revealed significant differences in the MSRS and "conscious motor processing". [Conclusion] These results suggest that "standing up while bowing" has limited effectiveness in promoting the STS motion because the coaching promotes internal focus.

Taiwanese reference values for the Short Physical Performance Battery in community-dwelling older adults.

OBJECTIVES: To establish reference values for SPPB score as well as test performances among Taiwanese community-dwelling older adults. METHODS: Participants included 847 older adults. The total scores and three subtest scores for the SPPB and the registered time to complete the walk and five-repetition sit-to-stand (STS) tests were determined and compared between sex and age (65-74, 75-84, and ≥85 years) groups. RESULTS: The mean SPPB total score was 10.9 in women and 10.5 in men. SPPB scores did not differ by sex, regardless of age group. However, the walk test (p = .030) and STS test (p = .008) timings were longer for men than for women in the 65-74-year-old group. The ≥85-year-old men achieved a lower balance score than did the 65-74-year-old men (p = .027). CONCLUSIONS: Population-specific SPPB reference values contribute to assessments of physical function and facilitate cross-cultural comparisons of physical performance.

[Get up, stand up! What sit-to-stand tests tell us about respiratory failure]. / Get up, stand up ! Ce que les tests de lever de chaise nous disent de l'insuffisance respiratoire.

Diseases associated with chronic respiratory failure have a negative impact on quality of life and life expectancy, notably through a reduction in patients' functional capacity. Assessing balance, coordination, muscular strength and endurance, as well as exercise tolerance, is therefore an important component of the evaluation of individuals with chronic respiratory failure. This evaluation can be made easier by using simple tools such as sit-to-stand tests. This review presents the main sit-to-stand tests that have been described and that can be used in everyday practice. The aim is to provide information to the clinician on the contribution of each test, and to identify the extent to which and the purpose for which these tests can be incorporated into a routine pulmonology and/or respiratory rehabilitation evaluation. Because of their inherently functional nature, these tests could help to identify the indications and/or the effects of respiratory rehabilitation.

Muscle synergy and kinematic synergy analyses during sit-to-stand motions in hallux valgus patients before and after treatment with Kinesio taping.

OBJECTIVES: To explore the impact of hallux valgus (HV) on lower limb neuromuscular control strategies during the sit-to-stand (STS) movement, and to evaluate the effects of Kinesio taping (KT) intervention on these control strategies in HV patients. METHODS: We included 14 young healthy controls (HY), 13 patients in the HV group (HV), and 11 patients in the HV group (HVI) who underwent a Kinesio taping (KT) intervention during sit-to-stand (STS) motions. We extracted muscle and kinematic synergies from EMG and motion capture data using non-negative matrix factorization (NNMF). In addition, we calculated the center of pressure (COP) and ground reaction forces (GRF) to assess balance performance. RESULTS: There were no significant differences in the numbers of muscle and kinematic synergies between groups. In the HV group, knee flexors and ankle plantar flexors were abnormally activated, and muscle synergy D was differentiated. Muscle synergy D was not differentiated in the HVI group. CONCLUSION: Abnormal activation of knee flexors and plantar flexors led to the differentiation of module D in HV patients, which can be used as an indicator of the progress of HV rehabilitation. KT intervention improved motor control mechanisms in HV patients.

Bioelectrical impedance phase angle combined with physical function predicts pre-frailty in maintenance hemodialysis patients: a prospective study.

BACKGROUND: The prevalence of pre-frailty is notably high among maintenance hemodialysis (MHD) patients. Pre-frailty, an early and reversible condition between non-frailty and frailty, can lead to adverse outcomes such as increased unplanned hospital admissions and a higher risk of other chronic diseases. Early identification and intervention of pre-frailty in MHD patients are crucial. This study aimed to establish a simple and effective model for screening and identifying MHD patients at high risk of pre-frailty by using 50 kHz-Whole Body Phase Angle (PhA) measured by bioelectrical impedance analysis (BIA), hand grip strength (HGS), the Five-Times-Sit-to-Stand Test (FTSST), and laboratory parameters, with a specific focus on gender differences. METHODS: This prospective cross-sectional study was conducted from September to December 2023 at the Wenjiang Hemodialysis Center in the Department of Nephrology, West China Hospital, Sichuan University, Chengdu, China. A total of 244 MHD patients, including 130 males and 114 females, were enrolled, comprising 128 non-frail and 116 pre-frail individuals. Data were collected prospectively, including demographic information, physical measurements, and laboratory test results. All participants provided informed consent before enrollment. The FRAIL scale (FS) was used to assess pre-frailty in MHD patients. Grip strength was measured using an electronic grip strength tester, physical function was assessed using the Five-Times-Sit-to-Stand Test, and whole-body phase angle was measured using the InBody S10 device. RESULTS: A total of 244 MHD patients with a mean age of 53.75 ± 0.90 years were enrolled, including 130 males with a mean age of 54.12 ± 1.26 years and 114 females with a mean age of 53.32 ± 1.29 years. ROC curve analysis showed that in male patients, the AUC of PhA for predicting pre-frailty was 0.919, with a sensitivity of 94.5% and specificity of 91.3%, and a cutoff value of 6.05°; in female patients, the AUC of PhA was 0.870, with a sensitivity of 70.5% and specificity of 90.6%, and a cutoff value of 5.25°. The AUC of FTSST for screening pre-frailty in male patients was 0.827, with a sensitivity of 62.3% and specificity of 96.2%, and a cutoff value of 12.95 s; in female patients, the AUC of FTSST was 0.784, with a sensitivity of 67.3% and specificity of 84.0%, and a cutoff value of 12.95 s. Additionally, in male patients, the combination of PhA and FTSST resulted in an AUC of 0.930, with a sensitivity of 96.4% and specificity of 81.3%; in female patients, the AUC was 0.911, with a sensitivity of 78.7% and specificity of 92.5%. CONCLUSION: PhA measured by BIA, in combination with the Five-Times-Sit-to-Stand Test, serves as an effective screening tool and predictor of pre-frailty in MHD patients. The combination of PhA and FTSST shows enhanced diagnostic value in female patients, while PhA alone is sufficient for predicting pre-frailty in male patients. TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2100051111), registered on 2021-09-13.

Brain (EEG) and muscle (EMG) activity related to 3D sit-to-stand kinematics in healthy adults and in central neurological pathology - A systematic review.

BACKGROUND: The sit-to-stand transfer is a fundamental functional movement during normal activities of daily living. Central nervous system disorders can negatively impact the execution of sit-to-stand transfers, often impeding successful completion. Despite its importance, the neurophysiological basis at muscle (electromyography (EMG)) and brain (electroencephalography (EEG)) level as related to the kinematic movement is not well understood. OBJECTIVES: This review synthesises the published literature addressing central and peripheral neural activity during 3D kinematic capture of sit-to-stand transfers. METHODS: A pre-registered systematic review was conducted. Electronic databases (PubMed, CINAHL Plus, Web of Science, Scopus and EMBASE) were searched from inception using search operators that included sit-to-stand, kinematics and EMG and/or EEG. The search was not limited by study type but was limited to populations comprising of healthy individuals or individuals with a central neurological pathology. RESULTS: From a total of 28,770 identified papers, 59 were eligible for inclusion. Ten of these 59 studies received a moderate quality rating; with the remainder rated as weak using the Effective Public Health Practice Project tool. Fifty-eight studies captured kinematic data of sit-to-stand with associated EMG activity only and one study captured kinematics with co-registered EMG and EEG data. Fifty-six studies examined sit-to-stand transfer in healthy individuals, reporting four dynamic movement phases and three muscle synergies commonly used by most individuals to stand-up. Pre-movement EEG activity was reported in one study with an absence of data during execution. Eight studies examined participants following stroke and two examined participants with Parkinson's disease, both reporting no statistically significant differences between their kinematics and muscle activity and those of healthy controls. SIGNIFICANCE: Little is known about the neural basis of the sit-to-stand transfer at brain level with limited focus in central neurological pathology. This poses a barrier to targeted mechanistic-based rehabilitation of the sit-to-stand movement in neurological populations.

The 1-min sit-to-stand test as a screening tool to assess exercise-induced oxygen desaturation in normoxemic people with interstitial lung disease.

BACKGROUND: In patients with interstitial lung disease (ILD), exercise-induced desaturation during the 6-min walk test (6MWT), specifically nadir oxygen saturation (nSpO2) of ≤88 % is a negative prognostic marker. As the 6MWT is often impractical for ILD patients, the aim of this study is to compare the 1-min sit-to-stand test (1minSTS) with the 6MWT to detect exercise-induced desaturation. METHODS: Participants were recruited from a tertiary referral clinic with both tests performed on the same day. Utilising Bland-Altman analysis, the relationship between nSpO2 on 1minSTS and 6MWT was determined. An area under the receiver operating characteristic curve (AUC) determined the ability of nSpO2 on 1minSTS test to predict SpO2 ≤88 % on 6MWT. RESULTS: Fifty participants completed the study (idiopathic pulmonary fibrosis n = 24, 48 %; connective tissue disease associated ILD n = 20, 40 %; other ILD n = 6, 12 %). Mean (SD) FVC%pred was 73 ± 16 %, mean DLCO%pred 57 ± 16 % and resting SpO2 99 ± 1 %. The 1minSTS resulted in less exercise-induced oxygen desaturation, with a median IQR nSpO2 of 95 % (89-98) and 93 % (85-96) respectively (p < 0.001). Moderate agreement was determined between the nSpO2 on both tests, with a mean difference of 3.2 % [-14 to +3.0 %]. The 1minSTS test accurately identified participants with nSpO2 ≤88 % on 6MWT (AUC 0.96). Oxygen desaturation ≤94 % during the 1minSTS test provided 100 % sensitivity and 87 % specificity for oxygen desaturation ≤88 % at 6MWT. CONCLUSION: This study demonstrates that exercise-induced oxygen desaturation during the 1minSTS test correlates with oxygen desaturation on 6MWT. The 1minSTS may be a practical screening tool for ILD patients who would benefit from further exercise testing.

Reference values for the 1-minute sit-to-stand and 5 times sit-to-stand tests to assess functional capacity: a cross-sectional study.

OBJECTIVES: To establish age-specific and sex-specific reference values and equations for the 1-minute sit-to-stand (1MSTS) and 5 times sit-to-stand (5TSTS) tests for Portuguese adults. DESIGN: Cross-sectional study. Descriptive statistics were explored to compute reference values and reference equations were established with a forward stepwise multiple regression. SETTING: Community. PARTICIPANTS: 546 adult volunteers without disabilities [age range 18 to 95 years; 58% female] were recruited. MAIN OUTCOME MEASURES: Data on age, sex, height, weight, body mass index (BMI), smoking status and physical activity were collected using a structured questionnaire developed specifically for this study. PROCEDURE: Participants performed three repetitions of the 1MSTS and 5TSTS and the best repetition was used for analysis. RESULTS: Normative values were provided by sex for each age decade. Reference equations were: 1MSTS= 61.53 - (0.34 x age) - (3.57 x sex) - (0.33 x BMI), r2 = 26%; and 5TSTS= 3.89 + (0.10 x age) - (0.96 x physical activity), r2 = 27%. CONCLUSIONS: The proposed reference values and equations will help to interpret the results of functional capacity obtained from healthy or diseased adult populations. CONTRIBUTION OF THE PAPER.

Energy expenditure and effort of patients with stroke during sit to stand: A pilot study.

Background: Sit-to-stand (STS) is a mechanically demanding task. Little is known about the energy expenditure (EE) and the perceived effort of patients with stroke during STS. Objectives: The objectives of our study were to assess the perceived effort and EE of patients with stroke when moving from STS and to determine whether an association between actual energy expended and patient-perceived effort exists. Method: This descriptive cross-sectional pilot study assessed participants' EE and perceived effort during STS, with a triaxial accelerometer and the modified Borg scale (MBS), respectively. Results: The team screened 428 individuals for potential inclusion, with nine participants (n = 5 female, 55.5%) meeting the criteria for our pilot study. Participants had a mean age of 52.77 (standard deviation [SD] ± 11.33) years, the majority had a haemorrhagic stroke (n = 6, 66.6%) and left hemiplegia (n = 6, 66.6%), and they were assessed 9.11 (SD ± 6.57) days post-stroke. The mean EE during STS was 2.82 (SD ± 1.9) kCal. Most participants (n = 7, 77.77%) perceived STS as more than a 'moderate' effort on the MBS. The correlation coefficient between the metabolic equivalent of task (METs) and MBS was r = 0.34 (p = 0.38). Conclusion: Our study found a fair positive correlation between METs and MBS for patients with stroke during STS. Clinical implications: The increased EE shown can be a key point for rehabilitation to lessen the extent of EE during STS. Further research is warranted.

The 1-min sit-to-stand test induces a significant and reliable level of neuromuscular fatigability: insights from a mobile app analysis.

PURPOSE: The performance metric associated with the execution of the 1-min sit-to-stand (1STS) typically relies on the number repetitions completed in 1 min. This parameter presents certain limitations (e.g., ceiling effect, motivational factors) which can impede its interpretation. Introducing additional parameters, such as neuromuscular fatigability level, could enhance the informative value of the 1STS and facilitate its interpretation. This study aimed to assess (i) whether the 1STS induces fatigability and (ii) the reliability of the fatigability level. METHODS: Forty young, healthy, and active participants underwent the 1STS twice during the same session. Isolated sit-to-stand maneuvers were performed before, immediately, and 1 min after completing the 1STS. A mobile app was utilized to obtain time (STST), velocity (STSV), and muscle power (STSP) from these sit-to-stand maneuvers. The pre-post change in these parameters served as the fatigability marker. Reliability was assessed using the intra-class correlation coefficient (ICC) and the coefficient of variation (CV). RESULTS: The mean number of repetitions during the 1STS was 63 ± 9. Significant decline in performance was observed for STST (13 ± 8%), STSV (-11.2 ± 6%), and STSP (-5.2 ± 3%), with more than 74% of participants exhibiting a decline beyond the minimal detectable change. Excellent between-session reliability (ICC ≥ 0.9; CV ≤ 5.3) was observed for the mobile app variables. CONCLUSION: The 1STS induces significant levels of fatigability. The fatigability indicators derived from the mobile app demonstrated remarkable reliability. Utilizing this user-friendly interface for computing fatigability may empower professionals to acquire insightful complementary indicators from the 1STS.

Sit-to-stand performance in children with cerebral palsy: a population-based cross-sectional study.

BACKGROUND: Sit-to-stand (STS) is one of the most commonly performed functional movements in a child's daily life that enables the child to perform functional activities such as independent transfer and to initiate walking and self-care. Children with cerebral palsy (CP) often have reduced STS ability. The aim of this study was to describe STS performance in a national based total population of children with CP and its association with age, sex, Gross Motor Function Classification System (GMFCS) level, and CP subtype. METHODS: This cross-sectional study included 4,250 children (2,503 boys, 1,747 girls) aged 1-18 years from the Swedish Cerebral Palsy Follow-Up Program (CPUP). STS performance was classified depending on the independence or need for support into "without support," "with support," or "unable." "With support" included external support from, e.g., walls and furniture. Physical assistance from another person was classified as "unable" (dependent). Ordinal and binary logistic regression analyses were used to identify associations between STS and age, GMFCS level, and CP subtype. RESULTS: 60% of the children performed STS without support, 14% performed STS with support, and 26% were unable or needed assistance from another person. STS performance was strongly associated with GMFCS level and differed with age and subtype (p < 0.001). For all GMFCS levels, STS performance was lowest at age 1-3 years. Most children with GMFCS level I (99%) or II (88%) performed STS without support at the age of 4-6 years. In children with GMFCS level III or IV, the prevalence of independent STS performance improved throughout childhood. CP subtype was not associated with STS performance across all GMFCS levels when adjusted for age. CONCLUSIONS: Independent STS performance in children with CP is associated with GMFCS level and age. Children with CP acquire STS ability later than their peers normally do. The proportion of children with independent STS performance increased throughout childhood, also for children with GMFCS level III or IV. These findings suggest the importance of maintaining a focus on STS performance within physiotherapy strategies and interventions for children with CP, including those with higher GMFCS level.

Exploring lower limb muscle activity and performance variations during instrumented Sit-to-Stand-to-Sit in sedentary individuals: Influence of limb dominance and testing modalities.

PURPOSE: to explore lower limb muscle activity concerning limb dominance, as well as variations in force and power during the standing up and sitting down phases of the instrumented sit-to-stand-to-sit test in sedentary individuals, across isokinetic and isotonic modalities. METHODS: 33 sedentary individuals underwent testing using a functional electromechanical dynamometer in both isokinetic and isotonic modes, accompanied by surface electromyography. RESULTS: In the isokinetic mode, the non-dominant gastrocnemius medialis and vastus medialis exhibited significantly (p < 0.05) higher muscle activity values during the standing up and sitting down phase compared to dominant counterparts. In the isotonic mode standing up phase, significant differences in muscle activity were noted for non-dominant gastrocnemius medialis, vastus medialis, and biceps femoris compared to their dominant counterparts. The sitting down phase in isotonic mode showed higher muscle activity for non-dominant vastus medialis compared to dominant vastus medialis. Regard to performance outcomes, significantly lower (p < 0.0001) values were observed for standing up (12.7 ± 5.1 N/kg) compared to sitting down (15.9 ± 6.1 N/kg) peak force, as well as for standing up (18.7 ± 7.8 W/kg) compared to sitting down (25.9 ± 9.7 W/kg) peak power in isokinetic mode. In isotonic mode, lower values were found for sitting down (6.5 (6.3-7.1) N/kg) compared to standing up (7.8 (7.3-8.9) N/kg) peak force and for sitting down (18.5 (13.2-21.7) W/kg) compared to standing up (33.7 (22.8-41.6) W/kg) peak power. CONCLUSIONS: Limb dominance influences lower-limb muscle activity during the instrumented sit-to-stand-to-sit test, and the choice of testing mode (isokinetic or isotonic) affects muscle engagement and performance outcomes.