Clinical Outcome of the Type A Acute Aortic Dissection Repair Using the "Tailored Stand-Up Collar" Technique.

PURPOSE: Achieving a secure anastomosis and complete hemostasis is essential for surgically treating type A acute aortic dissection (TAAAD). This study assessed the clinical feasibility of "tailored stand-up collar (TSC)" technique for constructing the distal stump. METHODS: We enrolled 68 patients who underwent ascending aortic repair for TAAAD. Patients were categorized according to the technique for distal stump construction: conventional (C) group using only a felt strip (32 cases); post-aortotomy (P) group, with a Hydrofit-felt strip attached after aortotomy (18 cases), and TSC group, where a Hydrofit-felt strip attached during cooling (18 cases). Pre-operative characteristics, procedural profiles, and post-operative outcomes were evaluated. RESULTS: The pre-operative characteristics were identical among the groups. The durations of cardiopulmonary bypass, hemostasis, and surgery were significantly shorter in the P and TSC groups. The duration of open distal in the TSC group (21 min) was significantly shorter than the other two groups. Post-operative additional procedures were not required for the TSC group and their post-operative hospital stay was significantly shorter (47.1% of patients were discharged within 2 weeks). CONCLUSION: The TSC technique would be practical because of its high reproducibility in terms of ease of use, shorter anastomotic time, and secure hemostasis.

Normative values of skeletal muscle mass, strength and performance in the Indian population.

BACKGROUND AND OBJECTIVES: Skeletal muscle is characterized by its mass, strength and performance. These normative values are pivotal in defining sarcopenia. Sarcopenia is associated with poor outcome of numerous medical and surgical conditions. This study aimed to establish normative benchmarks for skeletal muscle mass, strength and performance within the context of the Asian (Indian) population. METHODS: Our investigation utilized the computed tomography (CT) skeletal muscle index (SMI), handgrip strength (HGS), gait velocity and chair-stand test to construct reference values for muscle characteristics in the Indian population. RESULTS: The SMI analysis incorporated 1485 cases of acute abdomen (54.7%) males). The calculated SMI (kg/m2) was 38.50 (35.05-42.30) in males and 36.30 (32.20-41.20) in females (p = 0.510). The study also involved 3083 healthy individuals (67.6% males) evaluated for muscle strength and performance between August 2017 and August 2018. Notably, HGS (kg force) was recorded at 34.95 (26.50-43.30) in males and 25.50 (18.60-31.20) in females (p < 0.001). Gait velocity (metres/second) exhibited values of 1.25 (1.04-1.56) in males and 1.24 (1.03-1.56) in females (p = 0.851). Additionally, chair-stand test (seconds) results were 10.00 (9.00-13.00) in males and 12.00 (10.00-14.00) in females (p < 0.001). CONCLUSIONS: The investigation determined that males had greater muscle strength and performance than females. But gender wise, there was no significant difference in muscle mass. Interestingly, our population's muscle parameters were consistently lower compared to western literature benchmarks. These normative values will help to define sarcopenia parameters in our population, which have prognostic value in multiple ailments.

MocapMe: DeepLabCut-Enhanced Neural Network for Enhanced Markerless Stability in Sit-to-Stand Motion Capture.

This study examined the efficacy of an optimized DeepLabCut (DLC) model in motion capture, with a particular focus on the sit-to-stand (STS) movement, which is crucial for assessing the functional capacity in elderly and postoperative patients. This research uniquely compared the performance of this optimized DLC model, which was trained using 'filtered' estimates from the widely used OpenPose (OP) model, thereby emphasizing computational effectiveness, motion-tracking precision, and enhanced stability in data capture. Utilizing a combination of smartphone-captured videos and specifically curated datasets, our methodological approach included data preparation, keypoint annotation, and extensive model training, with an emphasis on the flow of the optimized model. The findings demonstrate the superiority of the optimized DLC model in various aspects. It exhibited not only higher computational efficiency, with reduced processing times, but also greater precision and consistency in motion tracking thanks to the stability brought about by the meticulous selection of the OP data. This precision is vital for developing accurate biomechanical models for clinical interventions. Moreover, this study revealed that the optimized DLC maintained higher average confidence levels across datasets, indicating more reliable and accurate detection capabilities compared with standalone OP. The clinical relevance of these findings is profound. The optimized DLC model's efficiency and enhanced point estimation stability make it an invaluable tool in rehabilitation monitoring and patient assessments, potentially streamlining clinical workflows. This study suggests future research directions, including integrating the optimized DLC model with virtual reality environments for enhanced patient engagement and leveraging its improved data quality for predictive analytics in healthcare. Overall, the optimized DLC model emerged as a transformative tool for biomechanical analysis and physical rehabilitation, promising to enhance the quality of patient care and healthcare delivery efficiency.

Biomechanics of sit-to-stand with dual tasks in older adults with and without mild cognitive impairment.

BACKGROUND: The decline in cognitive function in older adults with mild cognitive impairment (MCI) may contribute to a change in movement pattern during sit-to-stand transitions (STS). However, when comparing older adults with MCI to older adults without MCI, there is a lack of evidence of kinematic and kinetic data during STS. Furthermore, while significant cognitive dual-task interference has been demonstrated in older adults with MCI, studies on the effects of dual motor tasks in MCI, particularly during STS, have not been reported. RESEARCH QUESTION: Are there any differences in the movement time, joint angles, and maximum joint moments while performing STS under single- and dual-task conditions in older adults with and without MCI? METHODS: In a cross-sectional study, 70 participants were divided into two groups: older adults with MCI and without MCI. Motion analysis and a force plate system were used to collect and analyze the STS movement. All participants were asked to do the STS movement alone and the STS with a dual motor task with the self-selected pattern on an adjustable bench. RESULTS: Older adults with MCI had greater maximum trunk flexion during STS with a dual task than older adults without MCI and greater than STS alone. Furthermore, older adults with MCI had a greater ankle plantar flexion moment during STS with a dual task than during STS alone. SIGNIFICANCE: Even though the STS task is one of the simplest functional activities, different strategies to achieve the STS action with dual tasks were found among older adults with and without MCI in terms of joint angle and joint moments.

Two-and-a-Half-Year Follow-Up Study with Freedom on Water through Stand-Up Paddling: Exploring Experiences in Blue Spaces and Their Long-Term Impact on Mental Well-Being.

Blue space interventions evidently have a positive impact on well-being and mental health, yet longitudinal studies on the lasting impact of such interventions are scarce. In this qualitative follow-up study with semi-structured interviews, we explored the long-term experiences over 18-42 months among six out of the initial eight women from the primary study, also including two instructors from the initial study. The participants, dealing with mental disorders, participated in the group-based intervention Freedom on Water, participating in stand-up paddling. Five main themes emerged from the empirical analysis: SUP as a catalyst for broadening horizons; learning: stepping out of the comfort zone; a break from diagnosis and rumination; connectedness to nature, specifically blue nature, and to the group; a life-changing journey; and a shift in mindset. The study revealed a long-term, life-changing impact of the program on participants' well-being and mental health. Nature and blue space activities had become a greater part of their lives, improving their mental health with feelings of calmness, positivity, healing, and freedom. Stepping out of their comfort zone facilitated experiences of success and transformed their mindsets. Moreover, they experienced a break from rumination, and they became more outwardly focused, with confidence in themselves and their abilities, while making new friendships and engaging in new and different contexts.

The influence of smoothness and speed of stand-to-sit movement on joint kinematics, kinetics, and muscle activation patterns.

Background: Stand-to-sit (StandTS) is an important daily activity widely used in rehabilitation settings to improve strength, postural stability, and mobility. Modifications in movement smoothness and speed significantly influence the kinematics, kinetics, and muscle activation patterns of the movement. Understanding the impact of StandTS speed and smoothness on movement control can provide valuable insights for designing effective and personalized rehabilitation training programs. Research question: How do the smoothness and speed of StandTS movement affect joint kinematics, kinetics, muscle activation patterns, and postural stability during StandTS? Methods: Twelve healthy younger adults participated in this study. There were two StandTS conditions. In the reference condition, participants stood in an upright position with their feet positioned shoulder-width apart on the force plate. Upon receiving a visual cue, participants performed StandTS at their preferred speed. In the smooth condition, participants were instructed to perform StandTS as smoothly as possible, aiming to minimize contact pressure on the seat. Lower leg kinetics, kinematics, and coordination patterns of muscle activation during StandTS were measured: (1) angular displacement of the trunk, knee, and hip flexion; (2) knee and hip extensor eccentric work; (3) muscle synergy pattern derived from electromyography (EMG) activity of the leg muscles; and (4) postural sway in the anterior-posterior (A-P), medio-lateral (M-L), and vertical directions. Results: Compared to the reference condition, the smooth condition demonstrated greater eccentric knee extensor flexion and increased joint work in both the knee and hip joints. Analysis of specific muscle synergy from EMG activity revealed a significant increase in the relative contribution of hip joint muscles during the smooth condition. Additionally, a negative correlation was observed between knee extensor and vertical postural sway, as well as hip extensor work and M-L postural sway. Conclusion: Smooth StandTS facilitates enhanced knee eccentric control and increased joint work at both the hip and knee joints, along with increased involvement of hip joint muscles to effectively manage falling momentum during StandTS. Furthermore, the increased contributions of knee and hip joint work reduced postural sway in the vertical and M-L directions, respectively. These findings provide valuable insights for the development of targeted StandTS rehabilitation training.

Robust predictive control strategy of SCIG-based drive system.

This article presents a robust finite control set predictive scheme for a stand-alone squirrel cage induction generator (SCIG) drive. This technique is considered an alternative to the drive system due to the inclusion of system nonlinearities and fast dynamic response. The control objective in the distributed generation environment is to fix the output voltage to follow the stand-alone requirement. The strategy establishes optimized switching instants for cost function minimization for both source and load converter control and diminished cross-coupling amid active and reactive power during transient scenarios. The scheme is designed to achieve the minimal effect caused by the parameter uncertainties. During source and load changes, this work will also address the maintenance of dc-link voltage, machine, and load variables at the set value, supported by machine and load-end converter control to achieve stand-alone load objectives. In addition, the presented scheme is also tested with random variation of speed to check the efficacy of the control configuration. The drive performance is evaluated by simulation using MATLAB/Simulink environment. Comprehensive real-time findings obtained from a scaled laboratory test bench using dSPACE-1104 are provided to verify the feasibility of the predictive solution.

Pilot implementation and evaluation of the Sit-Stand e-Guide: an e-training program on the use of sit-stand workstations.

The 'Sit-Stand e-Guide' e-training program, designed to promote appropriate use of sit-stand workstations (SSWs), was evaluated for usability, acceptability and impact on various outcomes among SSW users. Participants from a large municipal organisation (25% male; mean age 45 [SD = 10.6] years) completed questionnaires pre-training (T0, n = 57), immediately post-training (T1, n = 50), and four weeks (T2, n = 46: primary endpoint) and twelve months later (T3, n = 30). High usability, acceptability and usefulness scores were reported at T1. Median [IQR] knowledge (4.4/5 [0.9]) and confidence (4.6/5 [1.0]) significantly increased at T1 compared to baseline (2.8 [1.2]; 3.3 [1.4]) and maintained at T2 and T3. At T2, mean [SD] sitting time (5.3 [1.2] h/workday) and low back discomfort (2.4 [2.3]) significantly decreased compared to baseline (6.1 [1.3] h; 3.4 [2.5] discomfort), SSW usage increased (1.4 [1.4]-2.8 [1.7] transitions), with no significant changes in work performance. Some behavioural changes were sustained at T3. The Sit-Stand e-Guide was acceptable and effective; evaluation across diverse workplaces and workers is now needed.

This study evaluated a novel, evidence-based e-training program to support the appropriate use of sit-stand workstations. The Sit-Stand e-Guide showed high usability, acceptability and effectiveness in enhancing workers' knowledge and awareness of sedentary behaviour and the use of their sit-stand workstation. It also improved sit/stand behaviour and low back discomfort. However, for long-term benefits, yearly refresher training is recommended.

Sarcopenia prevalence using handgrip strength or chair stand performance in adults living with type 2 diabetes mellitus.

BACKGROUND: The updated European Working Group on Sarcopenia in Older People (EWGSOP2) recommends handgrip strength (HGS) and the chair stand test (CST) to assess muscle strength, with the CST being a convenient proxy for lower limb strength. However, adiposity may differentially influence these strength criteria and produce discrepant sarcopenia prevalence. OBJECTIVE: To determine the prevalence of sarcopenia using HGS or the CST, and to investigate the associations between these strength criteria and adiposity in adults with type 2 diabetes mellitus. METHODS: The EWGSOP2 definition was used to assess the prevalence of probable (low muscle strength), confirmed (plus low muscle mass) and severe (plus poor physical performance) sarcopenia. Linear regression models were used to study the association between different measures of muscle strength and adiposity. RESULTS: We used data from 732 adults with type 2 diabetes mellitus (35.7% female, aged 64 ± 8 years, body mass index 30.7 ± 5.0 kg/m2). Using the CST compared with HGS produced a higher prevalence of probable (31.7% vs. 7.1%), confirmed (5.6% vs. 1.6%) and severe (1.0% vs. 0.3%) sarcopenia, with poor agreement between strength criteria to identify probable sarcopenia. CST performance, but not HGS, was significantly associated with all measures of adiposity in unadjusted and adjusted models. CONCLUSIONS: Higher levels of adiposity may impact CST performance, but not HGS, resulting in a higher prevalence of sarcopenia in adults with type 2 diabetes mellitus. Consideration should be paid to the most appropriate measure of muscle function in this population.

Relationship between natural muscle oscillation frequency and lower limb muscle performance during instrumented sit-to-stand and stand-to-sit movements on a novel device in sedentary subjects.

BACKGROUND: Despite the significance of muscle oscillation frequency, previous research has not established a correlation with muscle performance due to the challenges of applying resistance without altering natural motion during functional tests. RESEARCH QUESTION: What is the correlation between muscle oscillation frequency and lower limb muscle strength, power, and work during an instrumented sit-to-stand and stand-to- sit (iSTS-TS) task among sedentary subjects? METHODS: In a cross-sectional study, the oscillation frequency of the gastrocnemius medialis (GM), biceps femoralis (BF), and vastus medialis (VM) muscles in both the dominant (D) and non-dominant (ND) legs was assessed with a handheld myotonometer in 34 sedentary individuals before performing the iSTS-TS task. RESULTS: In the isokinetic mode, no significant correlations were found. In the isotonic mode, the BF muscle oscillation frequency in the D and ND legs exhibited significant positive correlations with peak force, peak power, and work during sitting down, as well as peak power and work during standing up. Positive correlations were observed in both legs between the GM oscillation frequency and sitting down peak force and work. Additionally, significant positive correlation was found with standing up work in the D leg. Muscle oscillation frequency of the VM exhibited a positive correlation with sitting down peak force in the ND leg. SIGNIFICANCE: Due to a greater number of correlations found, it is advisable to use the isotonic mode when assessing muscle oscillation frequency in relation to muscle performance during functional iSTS-TS tasks in sedentary subjects.

Evaluating Desk-Assisted Standing Techniques for Simulated Pregnant Conditions: An Experimental Study Using a Maternity-Simulation Jacket.

Lower back pain, a common issue among pregnant women, often complicates daily activities like standing up from a chair. Therefore, research into the standing motion of pregnant women is important, and many research studies have already been conducted. However, many of these studies were conducted in highly controlled environments, overlooking everyday scenarios such as using a desk for support when standing up, and their effects have not been adequately tested. To address this gap, we measured multimodal signals for a sit-to-stand (STS) movement with hand assistance and verified the changes using a t-test. To avoid imposing strain on pregnant women, we used 10 non-diseased young adults who wore jackets designed to simulate pregnancy conditions, thus allowing for more comprehensive and rigorous experimentation. We attached surface electromyography (sEMG) sensors to the erector spinae muscles of participants and measured changes in muscle activity, skeletal positioning, and center of pressure both before and after wearing a Maternity-Simulation Jacket. Our analysis showed that the jacket successfully mimicked key aspects of the movement patterns typical in pregnant women. These results highlight the possibility of developing practical strategies that more accurately mirror the real-life scenarios met by pregnant women, enriching the current research on their STS movement.

Can lower-limb exoskeletons support sit-to-stand motions in frail elderly without crutches? A study combining optimal control and motion capture.

With the global geriatric population expected to reach 1.5 billion by 2050, different assistive technologies have been developed to tackle age-associated movement impairments. Lower-limb robotic exoskeletons have the potential to support frail older adults while promoting activities of daily living, but the need for crutches may be challenging for this population. Crutches aid safety and stability, but moving in an exoskeleton with them can be unnatural to human movements, and coordination can be difficult. Frail older adults may not have the sufficient arm strength to use them, or prolonged usage can lead to upper limb joint deterioration. The research presented in this paper makes a contribution to a more detailed study of crutch-less exoskeleton use, analyzing in particular the most challenging motion, sit-to-stand (STS). It combines motion capture and optimal control approaches to evaluate and compare the STS dynamics with the TWIN exoskeleton with and without crutches. The results show trajectories that are significantly faster than the exoskeleton's default trajectory, and identify the motor torques needed for full and partial STS assistance. With the TWIN exoskeleton's existing motors being able to support 112 Nm (hips) and 88 Nm (knees) total, assuming an ideal contribution from the device and user, the older adult would need to contribute a total of 8 Nm (hips) and 50 Nm (knees). For TWIN to provide full STS assistance, it would require new motors that can exert at least 121 Nm (hips) and 140 Nm (knees) total. The presented optimal control approaches can be replicated on other exoskeletons to determine the torques required with their mass distributions. Future improvements are discussed and the results presented lay groundwork for eliminating crutches when moving with an exoskeleton.

Biomechanics of the lower limb in patients with mild knee osteoarthritis during the sit-to-stand task.

BACKGROUND: Knee osteoarthritis (KOA) is a prevalent and debilitating condition that markedly affects the sit-to-stand (STS) activity of patients, a prerequisite for daily activities. Biomechanical recognition of movements in patients with mild KOA is currently attracting attention. However, limited studies have been conducted solely on the observed differences in sagittal plane movement and muscle activation. AIM: This study aimed to identify three-dimensional biomechanical and muscle activation characteristics of the STS activity in patients with mild KOA. METHODS: A cross-sectional study was conducted to observe the differences between patients with mild KOA and a control group (CG). It was conducted to observe the differences in muscle activation, including root mean square (RMS%) and integrated electromyography (items), kinematic parameters like range of motion (ROM) and maximum angular velocity, as well as dynamic parameters such as joint moment and vertical ground reaction force (vGRF). RESULTS: Patients with mild KOA had a higher body mass index and longer task duration. In the sagittal plane, patients with KOA showed an increased ROM of the pelvic region, reduced ROM of the hip-knee-ankle joint, and diminished maximum angular velocity of the knee-ankle joint. Furthermore, patients with KOA displayed increased knee-ankle joint ROM in the coronal plane and decreased ankle joint ROM in the horizontal plane. Integrated vGRF was higher in both lower limbs, whereas the vGRF of the affected side was lower. Furthermore, patients showed a decreased peak adduction moment (PADM) and increased peak external rotation moment in the knee joint and smaller PADM and peak internal rotation moment in the ankle joint. The affected side exhibited decreased RMS% and iEMG values of the gluteus medius, vastus medialis, and vastus lateralis muscles, as well as a decreased RMS% of the rectus femoris muscle. Conversely, RMS% and iEMG values of the biceps femoris, lateral gastrocnemius, and medial gastrocnemius muscles were higher. CONCLUSION: The unbalanced activation characteristics of the anterior and posterior muscle groups, combined with changes in joint moment in the three-dimensional plane of the affected joint, may pose a potential risk of injury to the irritated articular cartilage.

Soil C:N:P stoichiometry in rhizosphere and non-rhizosphere of Pinus sylvestris var. mongolica forests.

The aim of this study was to reveal the stoichiometric characteristics of carbon, nitrogen and phosphorus in rhizosphere and non-rhizosphere soils of Pinus sylvestris var. mongolica in the Hulunbuir desert. We investigated the contents and stoichiometry of organic carbon, total nitrogen, and total phosphorus contents of rhizosphere and non-rhizosphere soils across different stand ages (28, 37 and 46 a) of P. sylvestris var. mongolica plantations, with P. sylvestris var. mongolica natural forest as the control. We analyzed the correlation between soils properties and soil stoichiometry. The results showed that rhizosphere effect significantly affected soil N:P, and stand age significantly affected soil organic carbon content in P. sylvestris var. mongolica plantation. Soil organic carbon content in plantation was significantly lower than that in natural forest. Soil organic carbon and total nitrogen contents of plantations in both rhizosphere and non-rhizosphere soils firstly decreased and then increased with increasing stand age, while total phosphorus firstly increased and then decreased in rhizosphere soils, and firstly decreased and then increased in non-rhizosphere soils. There was significant positive correlations between C:N and C:P in rhizosphere soils but not in non-rhizosphere soils, suggesting that higher synergistic rhizosphere soil N and P limitation. The mean N:P values of rhizosphere and non-rhizosphere soils were 4.98 and 8.40, respectively, indicating that the growth of P. sylvestris var. mongolica was restricted by soil N and the rhizosphere soils were more N-restricted. The C:N:P stoichiometry of rhizosphere and non-rhizosphere soils were significantly influenced by soil properties, with available phosphorus being the most important driver. The growth of P. sylvestris var. mongolica was limited by N in the Hulunbuir desert, and root system played an obvious role in enriching and maintaining soil nutrients. It was recommended that soil nitrogen should be supplemented appropriately during the growth stage of P. sylvestris var. mongolica plantation, and phosphorus should be supplemented appropriately according to the synergistic nature of nitrogen and phosphorus limitation.

Assertive community treatment as an alternative to incarceration for American pretrial detainees.

In the United States and elsewhere around the world, people with serious mental illness (SMI) are overrepresented in the criminal justice system. Clinical interventions to divert such individuals out of correctional settings, including Assertive Community Treatment (ACT), have been shown to reduce rates of criminal justice recidivism when modified to allow for the use of court sanctions to encourage treatment adherence. However, these interventions are noted to be underutilized as alternative to incarceration (ATI) programs. This paper summarizes the results of a retrospective cohort study conducted in a New York State forensic psychiatric hospital of 87 pretrial detainees admitted after being found incompetent to stand trial between January 2019 and January 2022. Of these, 49 patients were referred to an ACT team that served as an ATI program. The study outcomes noted that patients referred to this ACT team were 20% less likely to remain in pretrial detention than those that were not. Moreover, patients referred to the ACT program were also 34% more likely to be granted an ATI plea bargain in the community that did not involve serving a prison term. These results suggest that pretrial detainees with SMI are more likely to be granted an ATI program that offers more intensive treatment services such as ACT, due to the capability of such programs to also provide more intensive outreach and community supervision than traditional outpatient mental health service providers.

Orthostatic hypotension in Parkinson's disease: Sit-to-stand vs. supine-to-stand protocol and clinical correlates.

BACKGROUND: Screening for orthostatic hypotension (OH) is integral in Parkinson's disease (PD) management, yet evidence-based guidelines on best practice methods for diagnosing OH in PD are lacking. METHODS: We investigated the frequency and correlates of OH, symptomatic OH, and neurogenic OH, in a large consecutively recruited PD cohort (n = 318), and compared the diagnostic performance of the sit-to-stand vs. the supine-to-stand blood pressure (BP) test. We evaluated the utility of continuous BP monitoring and tilt table testing in patients with postural symptoms or falls who were undetected to have OH with clinic-based BP measurements. Disease severity, fluid intake, orthostatic and overactive bladder symptoms, falls, comorbidities and medication history were evaluated. RESULTS: Patients' mean age was 66.1 ± 9.5years, with mean disease duration 7.8 ± 5.5years. OH frequency was 35.8 % based on the supine-to-stand test. OH in PD was significantly associated with older age, lower body mass index, longer disease duration, worse motor, cognitive and overactive bladder symptoms and functional disabilities, falls, and lower fluid intake. A similar profile was seen with asymptomatic OH. Three quarters of OH were neurogenic, with the majority also having supine hypertension. The sit-to-stand test had a sensitivity of only 0.39. One quarter of patients were additionally diagnosed with OH during continuous BP monitoring. CONCLUSIONS: The sit-to-stand test substantially underdiagnoses OH in PD, with the important practice implication that supine-to-stand measurements may be preferred. Screening for OH is warranted even in asymptomatic patients. Adequate fluid intake, treatment of urinary dysfunction and falls prevention are important strategies in managing PD patients with OH.

Home-based resistance training performed at either fast or slow speeds improves power output in older adults.

PURPOSE: We investigated the effect of an unsupervised, body mass- home-based resistance training program in older adults performed at either a fast or slow contractile speed on changes to muscle-power, -volume, -architecture, and fatigue resistance of the knee extensors. METHODS: Thirty-two male older adults (age 65-88 years) were separated into 1) fast-speed exercise (Fast-group), 2) slow-speed exercise (Slow-group), and 3) no exercise (Control-group) groups. Participants in the exercise groups performed 30-45 repetitions of knee-extension and sit-to-stand exercises 3 times a week for 8 weeks with different exercise speed between the groups. Before and after the intervention period, the following variables were measured: Isotonic power, isometric strength, twitch contractile properties, muscle-activity, -architecture, and -quality, neuromuscular fatigue resistance of the knee extensors, and thigh muscle volume. RESULTS: Peak power was increased in both the Fast-group (+24 %, P < 0.01, d = 0.65) and Slow-group (+12 %, P < 0.05, d = 0.33) but not in the Control-group. Training increased pennation angle of the vastus lateralis in both the Fast-group (+8 %, P < 0.01, d = 0.42) and Slow-group (+8 %, P < 0.01, d = 0.42), while only the Fast-group showed increase in pennation angle of the rectus femoris (+12 %, P < 0.01, d = 0.64) and thigh muscle volume (+16 %, P < 0.01, d = 0.52). There was no time × group interaction effect for the other neuromuscular measures. CONCLUSIONS: Unsupervised, body mass- and home-based resistance training performed at either fast or slow speeds can improve muscle power in older adults, while fast-speed exercise may be preferable over slow-speed owing to the relatively greater improvement of muscle-power, -volume, -architecture, and better time efficiency.

ROBot-assisted physical training of older patients during acUte hospitaliSaTion-study protocol for a randomised controlled trial (ROBUST).

BACKGROUND: During hospitalisation, older patients spend most of their time passive in bed, which increases the risk of functional decline and negative adverse outcomes. Our aim is to examine the impact of robot-assisted physical training on functional status in older geriatric patients during acute hospitalisation. METHODS: This is a single-centre investigator-blinded placebo-controlled randomised controlled trial including geriatric patients aged ≥ 65 years, able to ambulate before hospitalisation, and with expected length of stay ≥ 2 days. In addition to standard physiotherapy treatment, the intervention group receive active robot-assisted resistance training and the control group passive robot-assisted sham training. Exclusion criteria are as follows: ambulation without assistance at the time of inclusion, known severe dementia, delirium, patients who have received less than three training sessions at discharge, terminal illness, recent major surgery/lower extremity fracture, conditions contradicting the use of training robot, lower extremity metastases, deemed unsuitable for robot-assisted training by a healthcare professional, or weight > 165 kg. The primary outcome is functional status assessed by change in Barthel Index-100 and 30-s chair stand test between inclusion and day of discharge. Secondary outcomes include functional status at 1- and 3-month follow-up, quality of life, depression, concern about falling, falls, cognition, qualitative interviews, need of homecare, discharge destination, readmissions, healthcare costs, sarcopenia, muscle quantity (bioimpedance), and mortality. Clinical meaningful change of the Barthel Index is 5 points. A recent study in geriatric patients reported a 6.9-point change following exercise. With a significance level of 5%, 80% power, and a drop-out rate of 20%, 244 participants per group (n = 488) are needed to detect the same mean difference. With a significance level of 5%, 80% power, and a drop-out rate of 20%, 74 participants per group (n = 148) are needed to detect a minimum clinical change of 2.6 repetitions for 30-s chair stand test. Recruitment started in January 2023 and is expected to continue for 19 months including follow-up. DISCUSSION: If our study shows that in-hospital robot-assisted training prevents functional decline in older patients, this may have a major impact on the individual patient due to increased wellbeing and a higher level of independency. In addition, society will benefit due to potential decrease in the need of municipality-delivered homecare following discharge. TRIAL REGISTRATION: ClinicalTrials.gov NCT05782855. Registration date: March 24, 2023.