Untrained Subjects Research Articles

A-357 Evaluation of a home kit for lay user collection, centrifugation, and refrigeration of capillary blood specimens

Abstract Background While solutions enabling at-home self-collection of capillary blood samples are maturing, many analytes require blood separation and controlled shipping temperatures for stable analysis in centralized laboratories. Here we present results of a pilot lay user study evaluating usability and specimen quality of at-home blood collection with centrifugation and refrigerated shipping of capillary serum specimens. Methods N=45 consented subjects were mailed kits including supplies for a capillary blood self-collection using a Tasso+™ device, a Labcorp TrueTherm™ reusable shipper containing a temperature tracker, a Labcorp TrueSpin™ battery-powered centrifuge, written instructions, and a usability survey. Subjects independently followed the instructions for blood collection, separation, and thermal protection and returned the kits to Labcorp via overnight shipping. Received kits were evaluated for correct return, volume of blood collected, volume of serum, visual hemolysis, and temperature throughout shipment. Results Of the n=45 consented subjects, 39 subjects returned the kits, one subject unsuccessfully attempted to collect blood two times, and the remaining five subjects did not return the kits. Primary analysis parameters are outlined in Table 1. Conclusions Untrained subjects were able to collect their own capillary blood samples, process them, and ship them using the investigational home collection kits. While kit return can be a challenge with home collection, the vast majority of subjects were able to return a testable sample. Combining blood separation prior to shipment using the Labcorp TrueSpin centrifuge and temperature control with the reusable Labcorp TrueTherm device successfully protected samples from hemolysis. These results indicate that such kits are a promising at-home blood collection method and may increase test accuracy and menu availability for sensitive analytes.

Improvement of Motor Task Performance: Effects of Verbal Encouragement and Music-Key Results from a Randomized Crossover Study with Electromyographic Data.

External motivational stimuli have been shown to improve athletic performance. However, the neurophysiological mechanisms underlying this improvement remain poorly understood. This randomized crossover study investigated the effects of music and verbal encouragement on measures of muscle excitation and myoelectric manifestations of fatigue in the biceps brachii and brachioradialis muscles during an endurance task. Fifteen untrained (mean age 29.57 ± 2.77 years) and 13 trained individuals (mean age 32.92 ± 2.90 years) were included. The endurance task, performed to exhaustion, consisted of keeping the dominant arm flexed to 90 degrees while holding a dumbbell loaded to 80% of 1RM with a supine grip in three randomized conditions: standard, with self-selected music, and with verbal encouragement. The untrained subjects showed an increase in task duration of 15.26% (p < 0.003) with music and 15.85% (p < 0.002) with verbal encouragement compared to the condition without external stimuli. There were no significant differences in the myoelectric manifestations of fatigue between the different conditions. Regarding the muscle excitation metrics, although the mean amplitude, peak value, and area under the curve remained unchanged across conditions, a significant reduction in the trend coefficient, indicating motor unit recruitment over time, was observed with both music (biceps brachii: -10.39%, p < 0.001; brachioradialis: -9.40%, p < 0.001) and verbal encouragement (biceps brachii: -7.61%, p < 0.001; brachioradialis: -6.51%, p < 0.001) compared to the standard condition. For the trained participants, no significant differences were observed between conditions in terms of task duration and outcome measures related to muscle excitation and myoelectric manifestations of fatigue, suggesting the possible presence of a ceiling effect on motivation. These results highlight the important role of external motivational stimuli, such as music and verbal encouragement, in improving task performance in untrained subjects, probably through more effective and efficient recruitment of motor units.

Effects of visual neuroplasticity training on visual perception, visual quality, and macular blood flow in patients with strabismus.

To observe the effects of visual neuroplasticity training on visual perception, visual quality, and macular blood flow in patients with concomitant strabismus postoperatively. In total, 108 patients underwent binocular strabismus correction operation, and some patients underwent neuroplasticity training. All patients underwent clinical ophthalmic examination, including measurement of best-corrected visual acuity, spherical equivalent, axis length, optical coherence tomography angiography, optical quality analysis system, and visual perception examinations. A total of 78 patients received neuroplasticity training for 1 month postoperatively, and 30 patients did not receive training. All patients underwent a visual perception examination preoperatively and at 1 day, 1 week, and 1 month postoperatively. Macular blood flow and visual quality were examined preoperatively and at 1 month postoperatively. Postoperative visual perception was better than preoperative visual perception (P < 0.05). After neuroplasticity training, the visual perception of the trained subjects was better than that of the untrained subjects (P < 0.05), and the blood flow in the macular area of the trained patients was lower than that of the untrained subjects (P < 0.05). The visual quality of the untrained subjects was lower than that of the trained patients (P < 0.05). Visual inspection system could accurately evaluate binocular visual perception in patients with concomitant strabismus. After surgical alignment of the strabismus patient, training can stimulate and integrate the formation of stereovision in a short period of time, maintain the visual quality of patients after surgery, and provide conditions for the formation of binocular visual signals and binocular stereovision, but in the short term, it will lead to the decrease of macular blood vessel density and perfusion density. However, the long-term effects of training have not been proven.

Effect of Jellyfish Body Parts and Presentation Form on Consumers Liking, Sensory Perception, Emotions, and Food Pairings.

Although jellyfish represent a food source in Asia, limited attention has been devoted to investigating Western consumers' perception and acceptance. This study explored the role of jellyfish body parts and presentation form in determining consumer perception. A local consumer test with 106 untrained subjects (57.5% female, 18-45 years) was performed in Italy over two days on six samples of jellyfish (Rhopilema esculentum Kishinouye) differing in terms of body parts (umbrella and oral arms) and presentation form (minced, striped, and pieced). For each sample, participants expressed their overall liking and, through three check-all-that-apply tests, described their perceived sensory properties and emotions and potential preferred food pairings. The results showed a significant effect of presentation form on liking (with striped and minced samples liked more than pieced samples), 18 sensory properties, four emotions, and five food pairings. Moreover, different drivers of liking and emotions were observed for three clusters of subjects named "In favour of", "Against", and "Picky towards" eating jellyfish. In conclusion, this study found that at least one segment of consumers could accept jellyfish as novel food. Moreover, the provided results could be useful for developing innovative jellyfish-based products and dishes that meet consumers' expectations.

Biomarkers of in vivo platelet activation in thoroughbreds during their first long-term training.

Physical exercise has an activating effect on platelet function that differs between trained and untrained subjects, depending on the type of exercise and training status. In humans, soluble P-selectin (sP-sel) and platelet-derived extracellular vesicles (PEVs) are considered reliable markers of in vivo platelet activation during exercise. In untrained humans, they increase after transient physical exercise, whereas long-term training induces a decrease in their resting levels due to an improved ability to adapt to hemodynamic changes. The aim of this study was to assess whether circulating levels of sP-sel and PEVs may be useful markers to explore in vivo platelet function in never-trained Thoroughbreds during their first 4 months of incremental training. A total of 29 clinically healthy, untrained Thoroughbreds (17 males and 12 females) were enrolled. All horses were trained with the same training schedule (90 days). Blood samples were collected on the day the training program began (T0), 30 days (T30), and 90 days (T90) after its incremental increase to quantify platelet count, sP-sel (horse enzyme-linked immunosorbent assay) and PEVs (flow cytometry). Statistical analysis was performed using RM one-way analysis of variance with the Geisser-Greenhouse correction. Soluble P-selectin tended to increase at T30 compared with T0, while T90 levels returned to baseline values. Significantly higher circulating levels of PEVs CD61+/AnnV+ were observed at T30 and T90 compared to baseline confirming platelet hyperactivity. The detection and quantification of sP-sel and PEVs in equine racehorses during the training period appears to be a promising tool to study exercise-induced primary hemostatic changes and may provide an important marker for exercise selection.

Cardiac biomarker responses following high-intensity interval and continuous exercise: the influence of ACE-I/D gene polymorphism and training status in men.

This study aimed to investigate the relationship between pre- and postexercise cardiac biomarker release according to athletic status (trained vs. untrained) and to establish whether the I/D polymorphism in the angiotensin-converting enzyme (ACE) gene had an influence on cardiac biomarkers release with specific regard on the influence of the training state. We determined cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in 29 trained and 27 untrained male soccer players before and after moderate-intensity continuous exercise (MICE) and high-intensity interval exercise (HIIE) running tests. Trained soccer players had higher pre (trained: 0.014 ± 0.007 ng/mL; untrained: 0.010 ± 0.005 ng/mL) and post HIIE (trained: 0.031 ± 0.008 ng/mL; untrained: 0.0179 ± 0.007) and MICE (trained: 0.030 ± 0.007 ng/mL; untrained: 0.018 ± 0.007) cTnI values than untrained subjects, but the change with exercise (ΔcTnI) was similar between groups. There was no significant difference in baseline and postexercise NT-proBNP between groups. NT-proBNP levels were elevated after both HIIE and MICE. Considering three ACE genotypes, the mean pre exercise cTnI values of the trained group (DD: 0.015 ± 0.008 ng/mL, ID: 0.015 ± 0.007 ng/mL, and II: 0.014 ± 0.008 ng/mL) and their untrained counterparts (DD: 0.010 ± 0.004 ng/mL, ID: 0.011 ± 0.004 ng/mL, and II: 0.010 ± 0.006 ng/mL) did not show any significant difference. To sum up, noticeable difference in baseline cTnI was observed, which was related to athletic status but not ACE genotypes. Neither athletic status nor ACE genotypes seemed to affect the changes in cardiac biomarkers in response to HIIE and MICE, indicating that the ACE gene does not play a significant role in the release of exercise-induced cardiac biomarkers indicative of cardiac damage in Iranian soccer players.NEW & NOTEWORTHY Our study investigated the impact of athletic status and angiotensin-converting enzyme (ACE) gene I/D polymorphism on cardiac biomarkers in soccer players. Trained players showed higher baseline cardiac troponin I (cTnI) levels, whereas postexercise ΔcTnI remained consistent across groups. N-terminal pro-brain natriuretic peptide increased after exercise in both groups, staying within normal limits. ACE genotypes did not significantly affect pre-exercise cTnI. Overall, athletic status influences baseline cTnI, but neither it nor ACE genotypes significantly impact exercise-induced cardiac biomarker responses in this population.

Sense of time is slower following exhaustive cycling exercise.

Subjective perception of time is altered during vigorous exercise. This could be due in part to the fatigue associated with physical activity at high intensities. The aim of this study was to determine the effect of fatigue, specifically, on subjective time perception. Twenty-six healthy, untrained subjects (17 men/9 women; age = 26.0 ± 4.3years; peak = 38.13 ± 5.62mL/kg/min) completed a maximal aerobic exercise test on a cycle ergometer. Time perception was assessed before (PRE) and after (POST) the exercise test using a time production task wherein subjects started a stopwatch and stopped it once they believed a designated time period had passed. This time produced with the stopwatch was the estimate of the target time that was compared to the target time interval. Relative error of the timing task was significantly higher for POST (0.112 ± 0.260) than for PRE (0.028 ± 0.173), p = .032, η2 = .178. Subjects produced ~ 8.4% more time than the target intervals when fatigued, which is indicative of a slower sense of time perception. A shift in attentional focus from timing to the sensations associated with fatigue is a possible factor to explain this result. Future studies which investigate the effects of exercise on time perception should consider the impact of fatigue experienced during exercise.

Effects on cardiorespiratory fitness of moderate-intensity training vs. energy-matched training with increasing intensity.

The present study investigated the role of training intensity in the dose-response relationship between endurance training and cardiorespiratory fitness (CRF). The hypothesis was that beginners would benefit from an increase in training intensity after an initial training phase, even if the energy expenditure was not altered. For this purpose, 26 weeks of continuous moderate training (control group, CON) was compared to training with gradually increasing intensity (intervention group, INC) but constant energy expenditure. Thirty-one healthy, untrained subjects (13 men, 18 women; 46 ± 8 years; body mass index 25.4 ± 3.3 kg m-2; maximum oxygen uptake, VO2max 34 ± 4 ml min-1 kg-1) trained for 10 weeks with moderate intensity [3 days/week for 50 min/session at 55% heart rate reserve (HRreserve)] before allocation to one of two groups. A minimization technique was used to ensure homogeneous groups. While group CON continued with moderate intensity for 16 weeks, the INC group trained at 70% HRreserve for 8 weeks and thereafter participated in a 4 × 4 training program (high-intensity interval training, HIIT) for 8 weeks. Constant energy expenditure was ensured by indirect calorimetry and corresponding adjustment of the training volume. Treadmill tests were performed at baseline and after 10, 18, and 26 weeks. The INC group showed improved VO2max (3.4 ± 2.7 ml kg-1 min-1) to a significantly greater degree than the CON group (0.4 ± 2.9 ml kg-1 min-1) (P = 0.020). In addition, the INC group exhibited improved Vmax (1.7 ± 0.7 km h-1) to a significantly greater degree than the CON group (1.0 ± 0.5 km h-1) (P = 0.001). The reduction of resting HR was significantly larger in the INC group (7 ± 4 bpm) than in the CON group (2 ± 6 bpm) (P = 0.001). The mean heart rate in the submaximal exercise test was reduced significantly in the CON group (5 ± 6 bpm; P = 0.007) and in the INC group (8 ± 7 bpm; P = 0.001), without a significant interaction between group and time point. Increasing intensity leads to greater adaptations in CRF than continuing with moderate intensity, even without increased energy expenditure. After 26 weeks of training in the moderate- and higher-intensity domain, energy-matched HIIT elicited further adaptations in cardiorespiratory fitness. Thus, training intensity plays a crucial role in the dose-response relationship between endurance training and fitness in untrained but healthy individuals. https://www.drks.de/DRKS00031445, identifier DRKS00031445.

Neuroplastic changes induced by long-term Pingju training: insights from dynamic brain activity and connectivity.

Traditional Chinese opera, such as Pingju, requires actors to master sophisticated performance skills and cultural knowledge, potentially influencing brain function. This study aimed to explore the effects of long-term opera training on the dynamic amplitude of low-frequency fluctuation (dALFF) and dynamic functional connectivity (dFC). Twenty professional well-trained Pingju actors and twenty demographically matched untrained subjects were recruited. Resting-state functional magnetic resonance imaging (fMRI) data were collected to assess dALFF differences in spontaneous regional brain activity between the actors and untrained participants. Brain regions with altered dALFF were selected as the seeds for the subsequent dFC analysis. Statistical comparisons examined differences between groups, while correlation analyses explored the relationships between dALFF and dFC, as well as the associations between these neural measures and the duration of Pingju training. Compared with untrained subjects, professional Pingju actors exhibited significantly lower dALFF in the right lingual gyrus. Additionally, actors showed increased dFC between the right lingual gyrus and the bilateral cerebellum, as well as between the right lingual gyrus and the bilateral midbrain/red nucleus/thalamus, compared with untrained subjects. Furthermore, a negative correlation was found between the dALFF in the right lingual gyrus and its dFC, and a significant association was found between dFC in the bilateral midbrain/red nucleus/thalamus and the duration of Pingju training. Long-term engagement in Pingju training induces neuroplastic changes, reflected in altered dALFF and dFC. These findings provide evidence for the interaction between artistic training and brain function, highlighting the need for further research into the impact of professional training on cognitive functions.

Physical Fitness Responses after Sixteen Weeks of Three Fitness Program Trainings in Untrained Subjects

Physical Fitness Responses after Sixteen Weeks of Three Fitness Program Trainings in Untrained Subjects

The effects of multiple factors on post-activation potentiation and performance enhancement: a narrative review

Purpose: The aim of this review was to examine the effects of various factors, including recovery time, conditioning activity, range of motion, gender, age, fiber type percentage, training experience, and supplement intake, on post-activation potentiation (PAP) and post-activation performance enhancement (PAPE). After clarifying the differences between these two potentiation strategies, the review examines the physiological mechanisms underlying these processes and their relationship with the aforementioned factors. Methods: A literature search was conducted in multiple databases, using as keywords those factors, PAP and PAPE. Results: PAP/PAPE appears to benefit athletes, adults, and individuals with a higher percentage of fast-twitch fibers more. To increase performance, it is recommended to use an intensity greater than 80% of one repetition maximum and high volumes. For trained subjects, a recovery time of 3 to 10 minutes is beneficial, while its effectiveness for untrained subjects is still unclear. Potentiation is greater when the primer exercise has a wide range of motion and is similar to the verification test. Additionally, supplementation with caffeine or creatine also contributes to the magnitude of potentiation. Finally, although there is evidence suggesting a net potentiation, the balance between fatigue and potentiation remains complex and unclear. Conclusions: Each factor that interacts with PAP and PAPE should be evaluated individually to ensure the most appropriate conditioning activity for the athlete.

Effects of modified hybrid resistance training on dynamic control ratio of knee joint in untrained healthy subjects

Background: Increased physical inactivity due to the COVID-19 pandemic has the potential to cause leg muscle strength decline due to the decrease in muscle mechanical loading. The hybrid training method uses the force generated by an electrically stimulated antagonist muscle to provide resistance to a voluntarily contracting agonist muscle. This exercise might be an effective choice for strengthening exercises during a pandemic because it does not require external resistance or stabilization devices. In addition, engaging the eccentric contraction of the antagonist muscle while the agonist is contracting concentrically may reduce agonist-antagonist muscle imbalance and reduce the risk of injury. Because the hybrid training system device was difficult to replicate, modifications were carried out using conventional stimulation tools. Methods: The research was conducted at the Medical Rehabilitation Installation of Dr. Soetomo General Academic Hospital Surabaya. The research subjects were 24 untrained healthy men aged 18-40 years divided into two groups: the treatment group who received modified hybrid strengthening exercises and the control group who received Russian protocol neuromuscular electrical stimulation (Russian NMES), 3 times per week for 4 weeks. Statistical tests were carried out on 12 treatment group subjects and 12 control group subjects who were able to complete the study. Results: There was a decrease in non-dominant 60o/sec DCR (p-value 0.002) and non-dominant 120o/sec DCR (p-value 0.019) in the treatment group. There was no significant difference in 60o/sec and 120o/sec DCR on both sides of the leg in the control group. There is a significant difference in ΔDCR between the two groups at non-dominant DCR 120o/sec (p-value 0.036). Conclusion: There was a greater reduction of knee joint DCR in the modified hybrid resistance training compared to the Russian NMES in untrained healthy subjects.

Intentionally Slow Concentric Velocity Resistance Exercise and Strength Adaptations: A Meta-Analysis.

Hermes, MJ and Fry, AC. Intentionally slow concentric velocity resistance exercise and strength adaptations: a meta-analysis. J Strength Cond Res 37(8): e470-e484, 2023-Intentionally slow-velocity resistance exercise (ISVRE) is suggested by some to be equally or more effective than fast or traditional velocities for increasing muscular strength. The purpose of this meta-analysis was to assess the effect ISVRE has on strength adaptations compared with faster or traditional velocities, with subgroup analyses exploring age, sex, and training status as confounding factors on the influence of velocity on strength adaptation. Eligible studies (n = 24) were required to be chronic (multiple weeks) randomized or nonrandomized comparative studies using dynamic constant external resistance for training and testing, and pre-post strength assessments. All studies examined healthy individuals (n = 625; fast or traditional n = 306, intentionally slow n = 319). A random-effects meta-analysis indicated a significant (p ≤ 0.05) effect in favor of fast training (effect size [ES] = 0.21, 95% confidence interval [CI] = 0.02-0.41, p = 0.03). Publication bias was noted through trim and fill analysis, with an adjusted effect size estimate of 0.32 (p < 0.001). Subgroup analyses indicated no difference between trained and untrained subjects (QM = 0.01, p = 0.93), and no difference between older and younger subgroups (QM = 0.09, p = 0.77), despite younger favoring faster (ES = 0.23, p = 0.049) and older not favoring either velocity (ES = 0.16, p = 0.46). Subgroup analysis also indicated women favored faster training (ES = 0.95, p < 0.001) in comparison to men (ES = 0.08, p = 0.58). Contrary to some previous reviews, these results indicate that chronic fast or traditional velocity resistance exercise increases muscular strength to a greater degree than ISVRE training. Resistance training velocity must be considered if strength is a desired outcome.

Steady-state redox status in circulating extracellular vesicles: A proof-of-principle study on the role of fitness level and short-term aerobic training in healthy young males.

Considering the role of redox homeostasis in exercise-induced signaling and adaptation, this study focuses on the exercise training-related intercellular communication of redox status mediated by circulating extracellular vesicles (EVs). 19 healthy young males were divided into trained (TG, 7) and untrained (UG, 12) subjects based on their VO2MAX. The UG subjects were further randomly distributed in experimental (UGEX, N = 7) and control (UGCTRL, N = 5) groups. The steady state of plasma EVs in TG and UGEX have been characterized for total number and size, as well as cargo redox status (antioxidants, transcription factors, HSPs) before, 3 and 24 h after a single bout of aerobic exercise (30', 70% HRM). Plasma EVs from UGEX and UGCTRL have been further characterized after 24 h from the last session of a 5-day consecutive aerobic training or no training, respectively. No differences were detected in the EVs' size and distribution at baseline in TG and UGEX (p>0.05), while the EVs cargo of UGEX showed a significantly higher concentration of protein carbonyl, Catalase, SOD2, and HSF1 compared to TG (p<0.05). 5 days of consecutive aerobic training in UGEX did not determine major changes in the steady-state number and size of EVs. The post-training levels of protein carbonyl, HSF1, Catalase, and SOD2 in EVs cargo of UGEX resulted significantly lower compared with UGEX before training and UGCTRL, resembling the steady-state levels in circulating EVs of TG subjects. Altogether, these preliminary data indicate that individual aerobic capacity influences the redox status of circulating EVs, and that short-term aerobic training impacts the steady-state redox status of EVs. Taking this pilot study as a paradigm for physio-pathological stimuli impacting redox homeostasis, our results offer new insights into the utilization of circulating EVs as biomarkers of exercise efficacy and of early impairment of oxidative-stress related diseases.

Time Course of Proteolysis Biomarker Responses to Resistance, High-Intensity Interval, and Concurrent Exercise Bouts.

Godwin, JS, Telles, GD, Vechin, FC, Conceição, MS, Ugrinowitsch, C, Roberts, MD, and Libardi, CA. Time course of proteolysis biomarker responses to resistance, high-intensity interval, and concurrent exercise bouts. J Strength Cond Res 37(12): 2326-2332, 2023-Concurrent exercise (CE) combines resistance exercise (RE) and high-intensity interval exercise (HIIE) in the same training routine, eliciting hypertrophy, strength, and cardiovascular benefits over time. Some studies suggest that CE training may hamper muscle hypertrophy and strength adaptations compared with RE training alone. However, the underlying mechanisms related to protein breakdown are not well understood. The purpose of this study was to examine how a bout of RE, HIIE, or CE affected ubiquitin-proteasome and calpain activity and the expression of a few associated genes, markers of skeletal muscle proteolysis. Nine untrained male subjects completed 1 bout of RE (4 sets of 8-12 reps), HIIE (12 × 1 minute sprints at V̇ o2 peak minimum velocity), and CE (RE followed by HIIE), in a crossover design, separated by 1-week washout periods. Muscle biopsies were obtained from the vastus lateralis before (Pre), immediately post, 4 hours (4 hours), and 8 hours (8 hours) after exercise. FBXO32 mRNA expression increased immediately after exercise (main time effect; p < 0.05), and RE and CE presented significant overall values compared with HIIE ( p < 0.05). There was a marginal time effect for calpain-2 mRNA expression ( p < 0.05), with no differences between time points ( p > 0.05). No significant changes occurred in TRIM63/MuRF-1 and FOXO3 mRNA expression, or 20S proteasome or calpain activities ( p > 0.05). In conclusion, our findings suggest that 1 bout of CE does not promote greater changes in markers of skeletal muscle proteolysis compared with 1 bout of RE or HIIE.

Detailed characterization of neural selectivity in free viewing primates

Fixation constraints in visual tasks are ubiquitous in visual and cognitive neuroscience. Despite its widespread use, fixation requires trained subjects, is limited by the accuracy of fixational eye movements, and ignores the role of eye movements in shaping visual input. To overcome these limitations, we developed a suite of hardware and software tools to study vision during natural behavior in untrained subjects. We measured visual receptive fields and tuning properties from multiple cortical areas of marmoset monkeys who freely viewed full-field noise stimuli. The resulting receptive fields and tuning curves from primary visual cortex (V1) and area MT match reported selectivity from the literature which was measured using conventional approaches. We then combined free viewing with high-resolution eye tracking to make the first detailed 2D spatiotemporal measurements of foveal receptive fields in V1. These findings demonstrate the power of free viewing to characterize neural responses in untrained animals while simultaneously studying the dynamics of natural behavior.

CARD1: Human Factors Evaluation of HeartMate 3 LVAD Peripherals: Insights gained from an Eye Tracking based Simulation Study

Background: Although left ventricular assist devices (LVADs) have demonstrated excellent clinical outcomes and design improvements over the past decade, human factors issues including limited usability and unintuitive handling continue to challenge this therapy. The aim of this study was to evaluate user experience of former LVAD patients and laypersons (LP) with the HeartMate 3 (HM3) LVAD peripherals in simulated everyday and emergency scenarios. Methods: This cross sectional, single center cohort study included former non-HM3 LVAD patients post heart transplantation (HTX) and LP without any previous LVAD peripherals handling experience. Seven predefined everyday and emergency scenarios, including battery exchanges (without alarm, in response to alarm, in dim light, within carry bag), power supply change to AC power, driveline dis- and reconnection and controller exchange were simulated. Subjects’ gaze behavior was recorded using eye tracking (ET) technology (Tobii Pro Glasses 2, Tobii Pro Lab), whereas areas of interest (AOIs) were defined for LVAD components used. Completion rate, duration to success (DTS), pump-off time, and percental fixation duration per AOI were defined as outcome measures to identify differences between initially successful and unsuccessful subjects and to correlate subject performances with demographics. Results: Thirty gender and age matched, untrained subjects (15 HTX vs. 15 LP, median age: 64 (IQR=11) vs. 63 (10) yrs., p=0.84), 20 vs. 20% female, p=1.00) completed 210 scenarios, whereas 82.9 vs. 81.9% (p=1.00) could be solved at first attempt. Changing power supply from batteries to AC power revealed highest complexity for both groups (DTS=251±93s, p=0.76): only 26.7% of subjects succeeded at first attempt (33.3% vs. 20.0%, p=0.68) and 56.7% at second attempt (66.7% vs. 46.7%, p=0.04) with significantly more LP failing. The first attempt resulted in 10 unnecessary hazards from disconnecting the driveline (5 HTX vs. 5 LP, pump-off time 2-118 s, p=0.25) and significant differences in percental fixation durations for five AOIs in participants with vs. without initial success (p<0.029, see Figure). Significantly decreased DTS during battery exchange (no alarm 32.5 (18.8)s vs. alarm 26.5 (20.8)s and dim light 21.0 (19.0)s, p<0.001, without group differences, p>0.34) indicate a high level of learnability and routine establishment. Exchanging batteries in the bag was more time consuming (75.0 (45.0) s, p=0.09), especially in elderly patients (r=0.61, p<0.001). Conclusion: This ET based human factors study provides insights into user experiences of untrained former non-HM3 LVAD patients and LP in handling HM3 peripherals in simulated everyday and emergency scenarios. It highlights unintuitive and potentially hazardous handling characteristics and provides guidance for future user centered design of LVAD wearables.

Application of european society of cardiology guidelines 2020 on competitive sports eligibility in a large population of subjects with surgically corrected congenital heart disease

Abstract Funding Acknowledgements Type of funding sources: None. Background Congenital heart disease (CHD) affects approximately 0.5-1% of the general population. Thanks to the improvement of medical and surgical techniques, in developed countries 90% of individuals with CHD reach adulthood and, consequently, the demand for participation in sporting activities also increases. Recently, the European Society of Cardiology have given recommendations on participation in recreational and competitive sports (ESC 2020) based on a clinical and functional algorithm. Purpose To show the prevalence of the eligibility for competitive sports proposed by ESC 2020 in a real CHD population and the prevalence of real engagement in physical activity (both competitive and non-competitive). Also, to evaluate the difference in cardiorespiratory fitness (CRF) and the impact of training among different sport eligibility classes. Methods Retrospective study of 401 patients with surgically corrected CHD and followed up with cardiopulmonary exercise test (CPET) performed on treadmill or cycle ergometer until patients’ exhaustion. Subjects were divided in 4 classes according with ESC 2020 guidelines and corresponding to the eligibility for all competitive sport (A), all except endurance specialties (B), only for skill disciplines (C) or not eligible (D). Results Median (IQR) age was 18.0(13.0; 21.5) years; 266 patients (66.3%) were males. 34% were in class D, 13% in class B, 25% in class C and 28% in class A. Within the entire population, 179 subjects (44.6%) carried out structured exercise training, corresponding to 60.7% of subjects in class A, 45.1% of those in class B, 41.7% of those in class C and 41.1% of those in class D. VO2peak/Kg was similar between class A [39.2 (33.6-44.4) mL/Kg/min] and B [37.9 (30.6-42.6) mL/Kg/min], but significantly different between class A vs. class C [33.3 (28.3-41.4) mL/Kg/min p&amp;lt;.0001] and class D [32.2 (27.6-39.3) mL/Kg/min p&amp;lt;.0001]. Also, functional impairment, defined as &amp;lt;85% of the predicted for age and sex, resulted significantly higher in patients in the lower classes of sport eligibility (C and D) than in the higher ones, with a prevalence of impaired CRF of 22.5% in class A, 42.5% in class B, 55.1% in class C and 57.0% in class D (p &amp;lt;.0001). Paired comparison showed significant differences in CRF (VO2peak/Kg) between trained and untrained subjects both within and across ESC 2020 classes, while there was no significant difference between paired groups of different classes who presented the same level of physical activity (Figure 1). Conclusions Subjects in class A had better functional capacity than those in C and D classes, but exercise training (competitive or non-competitive) can have a significant impact on CRF level. Figure 1 shows that trained people in D class had higher CRF than untrained in A class, supporting that functional evaluation and an individualized exercise prescription may recruit functional "reserve" by improving the VO2peak as key prognostic component.

Self-Movement Screening using the Symmio Application is Reliable and Valid for Identifying Musculoskeletal Risk Factors.

Musculoskeletal health problems are one of the greatest healthcare expenses in the United States but patient-driven screening procedures to detect risk factors do not exist. The purpose was to establish the inter-rater reliability of the Symmio Self-Screen application in untrained individuals and to investigate its accuracy to detect MSK risk factors such as pain with movement, movement dysfunction, and decreased dynamic balance. Cross-Sectional. Eighty (42 male, 38 female) healthy individuals mean age 26.5 ± 9.4 participated in the study. The inter-rater reliability of Symmio application was established by comparing self-screen scores from untrained subjects with the results simultaneously determined by a trained healthcare provider. Each subject was evaluated for pain with movement, movement dysfunction, and deficits in dynamic balance by two trained evaluators who were blinded to the Symmio results. The validity of Symmio was determined by comparing self-screen performance dichotomized as pass or fail with the reference standard of pain with movement, failure on the Functional Movement Screen™, and asymmetry on the Y Balance Test-Lower Quarter™ using three separate 2x2 contingency tables. The mean Cohen's kappa coefficient was 0.68 (95% CI, 0.47-0.87) and the absolute agreement was 89% between self-assessment of subjects and the observation of a trained healthcare provider. There were significant associations for the presence of pain with movement (p=0.003), movement dysfunction (p=0.001), and dynamic balance deficits (p=0.003) relative to poor Symmio performance. The accuracy of Symmio to identify pain with movement, movement dysfunction, and dynamic balance deficits were 0.74 (95% CI, 0.63-0.83), 0.73 (95% CI, 0.62-0.82), and 0.69 (95% CI, 0.57-0.79), respectively. The Symmio Self-Screen application is a reliable and feasible screening tool that can be used to identify MSK risk factors. Level 2.

Validity and Reliability of Facial Rating of Perceived Exertion Scales for Training Load Monitoring.

van der Zwaard, S, Hooft Graafland, F, van Middelkoop, C, and Lintmeijer, LL. Validity and reliability of facial rating of perceived exertion scales for training load monitoring. J Strength Cond Res 37(5): e317-e324, 2023-Rating of perceived exertion (RPE) is often used by coaches and athletes to indicate exercise intensity, which facilitates training load monitoring and prescription. Although RPE is typically measured using the Borg's category-ratio 10-point scale (CR10), digital sports platforms have recently started to incorporate facial RPE scales, which potentially have a better user experience. The aim of this study was to evaluate the validity and reliability of a 5-point facial RPE scale (FCR5) and a 10-point facial RPE scale (FCR10), using the CR10 as a golden standard and to assess their use for training load monitoring. Forty-nine subjects were grouped into 17 untrained (UT), 19 recreationally trained (RT), and 13 trained (T) individuals Subjects completed 9 randomly ordered home-based workout sessions (3 intensities × 3 RPE scales) on the Fitchannel.com platform. Heart rate was monitored throughout the workouts. Subjects performed 3 additional workouts to assess reliability. Validity and reliability of both facial RPE scales were low in UT subjects (intraclass correlation [ICC] ≤ 0.44, p ≤ 0.06 and ICC ≤ 0.43, p ≥ 0.09). In RT and T subjects, validity was moderate for FCR5 (ICC ≥ 0.72, p < 0.001) and good for FCR10 (ICC ≥ 0.80, p < 0.001). Reliability for these groups was rather poor for FCR5 (ICC = 0.51, p = 0.006) and moderate for FCR10 (ICC = 0.74, p < 0.001), but it was excellent for CR10 (ICC = 0.92, p < 0.001). In RT and T subjects, session RPE scores were also strongly related to Edward's training impulse scores ( r ≥ 0.70, p < 0.001). User experience was best supported by the FCR10 scale. In conclusion, researchers, coaches, strength and conditioning professionals, and digital sports platforms are encouraged to incorporate the valid and reliable FCR10 and not FCR5 to assess perceived exertion and internal training load of recreationally trained and trained individuals.