A hop testing alternative for functional performance following anterior cruciate ligament reconstruction.

The purpose of this work was to provide a simple method to determine reactive strength during the 6-meter timed hop test (6mTH) and evaluate its association with isokinetic peak torque in patients following anterior cruciate ligament reconstruction (ACLR). Twenty-nine ACLR patients who were at least four months from surgery were included in this analysis. Participants were brought into the laboratory on one occasion to complete functional testing. Quadriceps and hamstring isokinetic testing was completed bilaterally at 60, 180, and 300 deg∙s-1, using extension peak torque from each speed as the outcome measure. The 6mTH was completed bilaterally using a marker-based motion capture system, and reactive strength ratio (RSR) was calculated from the vertical velocity of the pelvis during the test. An adjustment in RSR was made using the velocity of the 6mTH test to account for different strategies employed across participants. Repeated measures correlations were used to determine associations among isokinetic and hop testing variables. A two-way mixed analysis of variance was used to determine differences in isokinetic and hop testing variables between operated and non-operated legs and across male and female participants. Moderate positive associations were found between RSR (and adjusted RSR) and isokinetic peak torque at all speeds (r = .527 to .577). Mean comparisons showed significant main effects for leg and sex. Patients showed significant deficits in their operated versus non-operated legs in all isokinetic and hop testing variables, yet only isokinetic peak torque and timed hop time showed significant differences across male and female groups. Preliminary results are promising but further development is needed to validate other accessible technologies available to calculate reactive strength during functional testing after ACLR. Pending these developments, the effects of movement strategies, demographics, and levels of participation on RSR can then be explored to translate this simple method to clinical environments.

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.

Velocity-Based Training Affects Function, Strength, and Power in Persons with Parkinson's Disease.

ABSTRACT: Calaway, CC, Martinez, KJ, Calzada Bichili, AR, Caplan, JH, Milgrim, WP, Mann, JB, Haq, I, and Signorile, JF. Velocity-based training affects function, strength, and power in persons with Parkinson's disease. J Strength Cond Res XX(X): 000-000, 2024-Velocity-based training (VBT) is commonly associated with high-level athletes. No study has examined the effects of VBT on performance in persons with Parkinson's disease (PD). The objective of the study was to compare the effects of 10 and 30% velocity-loss threshold protocols on changes in functional performance, strength, and power in persons with PD after 12 weeks of supervised VBT, 3 days per week. Twenty-one subjects with PD (72.9 ± 5.9 y) were randomly assigned to the 10% or 30% velocity-loss threshold group and performed the 6-m walk test at habitual and maximal gait speed (6MWTMax), the 5 time sit-to-stand test (5 × STS), 1 repetition maximum (1RM), and peak power (PP) testing for the chest press (CP) and leg press (LP) exercise. A mixed ANOVA with significance was set a priori at 0.05 revealed that significant time effects were seen for the 6MWT at maximal speed (MDiff ± SD = 0.22 ± 0.04 m·s-1, p < 0.001), 5-time sit-to-stand time (-1.48 ± 0.45 seconds, p = 0.005) and power (75.5 ± 22.7 W, p = 0.005), 1RM for CP (5.1 ± 1.1 kg, p < 0.001) and LP (12.6 ± 3.7 kg, p = 0.005), and LP-PP (43.6 ± 13.2 W, p = 0.006). Secondary analyses revealed time effects for the load at which PP was achieved for the CP exercise. A Wilcoxon signed-rank test revealed no significant differences in the percentage of 1RM at which PP was achieved for either condition. Results indicate that VBT is an effective training modality for improving functional capacity, strength, and power in persons with PD; however, shifts in force-velocity relationships were not evidenced.

Choriocapillaris Perfusion after 8 Weeks of High-Speed Circuit Training in Older Healthy Adults.

PURPOSE: The aim of this study was to examine the impact of an 8-week high-speed circuit resistance training program (HSCT) on choriocapillaris density (CCD) in healthy older adults. METHODS: Eighteen cognitively normal older adults were enrolled and randomly assigned to either the HSCT or the control group (CON). The HSCT group was comprised of 11 participants who trained three times a week for eight weeks, while the CON group consisted of 7 participants who did not engage in formal training. Optical coherence tomography angiography (OCTA) was employed to image both eyes of each subject at baseline and at the 8-week follow-up. The choriocapillaris density (CCD) of 2.5 mm in diameter centered on the fovea was measured. RESULTS: The average age of the HSCT group was 70.3 ± 5.7 years, which was not different from the CON group (average age: 71.6 ± 5.2 years, p = 0.62). There were no significant changes in CCD between baseline and the 8-week follow-up in either the HSCT or the CON group-specifically, the baseline CCD in the HSCT group was 63.3% ± 5% (Mean ± SD), which did not differ significantly from the 8-week follow-up after HSCT training (64.7% ± 4%, p = 0.19). Likewise, there was no significant difference in CCD between baseline and the 8-week follow-up in the CON group (63.3% ± 3% and 62.7% ± 5%, respectively, p = 0.66). CONCLUSION: CCD appeared to remain stable after 8 weeks of HSCT in healthy older individuals, possibly due to autoregulation. Further research with extended training may be necessary to verify these findings.

The Impact of Velocity-Based Training on Load-Velocity Relationships in Leg Press and Chest Press for Older Persons.

ABSTRACT: Calaway, C, Mishra, S, Parrino, R, Martinez, KJ, Mann, JB, and Signorile, JF. Velocity-based training affects the load-velocity relationship in leg press and chest press for older persons. J Strength Cond Res 38(6): 1136-1143, 2024-This study examined the impact of 3 months of velocity-based training (VBT) on chest press (CP) and leg press (LP) maximal strength (1 repetition maximum [1RM]), peak power (PP), and percentage load where PP was achieved (%1RMPP) in older adults. Twenty-nine subjects were assigned to either a velocity-deficit (VD) group or a force-deficit (FD) group for each exercise depending on their load-velocity (LV) curves. Changes in load were determined by the ability to maintain either 90% (VD) or 70% (FD) of their PP during training. Subjects' powers were tested before and after the training intervention at loads between 40 and 80%1RM. Separate 2 (group) × 2 (time) ANOVA was used to examine changes in each variable by group for each exercise. Wilcoxon signed-rank tests were used to determine whether significant changes in %1RMPP for each exercise and group. For chest press 1 repetition maximum, there were no significant main effects or interaction. Significant main effects for time were observed for leg press 1 repetition maximum ( p < 0 .001, η2 = 0.547) and chest press peak power ( p = 0.009, η2 = 0.243). For LPPP, there were no significant main effects or interactions. For %1RMPP, CP median scores revealed no significant changes for either group. Significant declines in %1RMPP were observed for leg press velocity-deficit and leg press force-deficit ( p < 0.03) groups. Velocity-based training was effective at improving 1RM, PP, and shifting %1RMPP in the LP groups. These results have implications for targeting power improvements at specific areas of the LV curve. Health care providers and trainers should consider these findings when constructing exercise programs to counter age-related declines in older adults.

Decreased retinal capillary density as a beneficial response to 24-week high-speed circuit resistant training in healthy older adults.

PURPOSE: To determine the changes in retinal microvascular density after a 24-week high-speed circuit resistance training program (HSCT) in healthy older adults. METHODS: Thirty healthy older adults were recruited and randomly assigned to either a training group (HSCT) or a non-training (CON) group. Fifteen subjects (age 73.3 ± 7.76 yrs) in the HSCT group exercised three times per week on non-consecutive days for 24 weeks. Fifteen subjects in the CON group (age 72.2 ± 6.04 yrs) did not have formal physical training. Both eyes of each subject were imaged using optical coherence tomography angiography (OCTA) at baseline and at the 24-week follow-up. The vessel densities of the retinal vascular network (RVN), superficial vascular plexus (SVP), and deep vascular plexus (DVP) were measured. RESULTS: There were no demographic differences between the study groups. There were significant decreases in the retinal vessel densities of RVN, SVP and DVP in the HSCT group (P < 0.05). However, there were no significant changes in all three vascular measurements in the CON group (P > 0.05), although the changes showed a decreasing trend. The decreased vessel densities were doubled in the HSCT group in comparison to the CON group. However, the differences between groups did not reach a significant level (P > 0.05). CONCLUSIONS: This is the first study to reveal the decreased retinal vessel densities as a possible imaging marker for the beneficial effects of the 24-week HSCT program in older adults.

Leg Press and Chest Press Power Normative Values by Half Decade in Older Women.

ABSTRACT: Parrino, RL, Martinez, KJ, Konlian, JA, Conti, JM, and Signorile, JF. Leg press and chest press power normative values by half decade in older women. J Strength Cond Res 38(5): 991-998, 2024-Neuromuscular power is essential for the performance of most activities of daily living and the maintenance of functional independence throughout the aging process. Power declines rapidly in later life; however, this decline may be reduced or delayed with early detection and intervention. Therefore, this study provides leg press and chest press power normative values for older women. Women's power data for this analysis included 229 participants, 60-90 years of age. Power testing was conducted on Keiser A420 pneumatic leg press and chest press machines following a standardized protocol. Data were stratified into half-decade age groups and analyzed using a 1-way ANOVA. Descriptive statistics and quartile rankings are reported, and significant differences between age groups are outlined. There were significant differences in absolute and relative leg press peak power between the age groups ( p < 0.05). However, there were no significant differences in absolute or relative chest press peak power between the age groups. This research established normative values and quartile rankings for leg press and chest press power in older women 60-90 years of age, allowing comparative evaluations with patients and subjects by clinicians and researchers, respectively. These values should improve exercise interventions designed to improve power production by providing assessments of subjects' current status and allowing comprehensive monitoring of progress.

Impact of Quadriceps Tendon Graft Thickness on Electromechanical Delay and Neuromuscular Performance After ACL Reconstruction.

Background: Both partial- and full-thickness quadriceps tendon (QT) graft harvests are used for anterior cruciate ligament reconstruction (ACLR). Purpose: To evaluate the impact of QT graft harvest depth (full or partial thickness) on electromechanical delay (EMD), peak torque (PT), and rate of torque development (RTD) after ACLR. Study Design: Controlled laboratory study. Methods: A total of 26 patients who underwent either partial-thickness (n = 14) or full-thickness (n = 12) autograft QT ACLR were recruited between June and November 2021 (>1 year before participation). Patients performed isokinetic knee extension testing with surface electromyography of the quadriceps muscles. Mixed repeated-measures analysis of variance with least significant difference post hoc testing was used to determine significant differences (mean difference [MD] ± SE) or interactions for all variables. Results: A significant speed×depth interaction was seen for the vastus medialis (P = .005). Pairwise analyses showed significantly longer EMD for the partial-thickness graft than the full-thickness graft (MD ± SE, 19.92 ± 6.33 ms; P = .006). In the partial-thickness graft, the EMD was significantly longer at 90 deg/s versus 180 deg/s (MD ± SE, 19.11 ± 3.95 ms; P < .001) and 300 deg/s (MD ± SE, 16.43 ± 5.30 ms; P = .006). For PT, the full-thickness graft had a significantly lower PT on the operated versus nonoperated side at all speeds (MD ± SE: 90 deg/s, -57.0 ± 10.5 N·m, P < .001; 180 deg/s, -26.0 ± 10.2 N·m, P = .020; 300 deg/s, -20.3 ± 8.9 N·m, P = .034). For RTD, the full-thickness graft showed significantly Slower RTD for the operated versus nonoperated side at all time points (MD ± SD: RTD0-25 (0-25% of the range of motion), -131.3 ± 50.9 N·m/s, P = .018; RTD25-50, -197.0 ± 72.5 N·m/s, P = .014; RTD50-75, -113.3 ± 39.8 N·m/s, P = .013; RTD75-100, -149.4 ± 35.9 N·m/s, P < .001). Conclusion: Compared with partial-thickness QT, full-thickness QT showed a shorter vastus medialis EMD at higher loading, and therefore greater stiffness, as well as slower RTD and lower PT across all testing speeds. Clinical Relevance: The impact of full-thickness QT autograft on EMD and neuromuscular performance should be considered for ACLR.

A comparison of three-dimensional kinematics between markerless and marker-based motion capture in overground gait.

Vision-based methods using RGB inputs for human pose estimation have grown in recent years but have undergone limited testing in clinical and biomechanics research areas like gait analysis. The purpose of the present study was to compare lower extremity kinematics during overground gait between a traditional marker-based approach and a commercial multi-view markerless system in a sample of subjects including young adults, older adults, and adults diagnosed with Parkinson's disease. A convenience sample of 35 adults between the age of 18-85 years were included in this study, yielding a total of 114 trials and 228 gait cycles that were compared between systems. A total of 30 time normalized waveforms, including three-dimensional joint centers, segment angles, and joint angles were compared between systems using root mean-squared error (RMSE), range of motion difference (ΔROM), Pearson correlation coefficients (r), and interclass correlation coefficients (ICC). RMSEs for joint center positions were less than 28 mm in all joints with correlations indicating good to excellent agreement. RMSEs for segment and joint angles were in range of previous results, with highest agreement between systems in the sagittal plane. ΔROM differences were within reference values that characterize clinical groups like Parkinson's disease, stroke, or knee osteoarthritis. Further improvements in pelvis tracking, markerless keypoint model definitions, and standardization of comparison study protocols are needed. Nevertheless, markerless solutions seem promising toward unrestricted motion analysis in biomechanics research and clinical settings.

Prediction of gait kinetics using Markerless-driven musculoskeletal modeling.

Video-based motion analysis systems are emerging in the biomechanics research community, yet there is limited exploration of kinetics prediction using RGB-markerless kinematics and musculoskeletal modeling. This project aimed to provide ground reaction force (GRF) and ground reaction moment (GRM) predictions during over-ground gait by introducing RGB-markerless kinematics into a musculoskeletal modeling framework. Full-body markerless kinematic inputs and musculoskeletal modeling were used to obtain GRF and GRM predictions which were compared to measured force plate values. The markerless-driven predictions yielded average root mean-squared error (RMSE) in the stance phase of 0.035 ± 0.009 N∙BW-1, 0.070 ± 0.014 N∙BW-1, and 0.155 ± 0.041 N∙BW-1 in the mediolateral (ML), anteroposterior (AP), and vertical (V) GRFs. This was accompanied by moderate to high correlations and interclass correlation coefficients (ICC) indicating moderate to good agreement between measured and predicted values (95% Confidence Inervals: ML = [0.479, 0.717], AP = [0.714, 0.856], V = [0.803, 0.905]). For ground reaction moments (GRM), average RMSE was 0.029 ± 0.013 Nm∙BWH-1, 0.014 ± 0.005 Nm∙BWH-1, and 0.005 ± 0.002 Nm∙BWH-1 in the sagittal, frontal, and transverse planes. Pearson correlations and ICCs indicated poor agreement between systems for GRMs (95% Confidence Intervals: Sagittal = [0.314, 0.608], Frontal = [0.006, 0.373], Transverse = [0.269, 0.570]). Currently, RMSE is larger than target thresholds set from studies using Kinect, inertial, or marker-based kinematic drivers; but methodological considerations highlighted in this work may help guide follow-up iterations. At this point, further use in research or clinical practice is cautioned until methodological considerations are addressed, although results are promising at this point.

Validity of artificial intelligence-based markerless motion capture system for clinical gait analysis: Spatiotemporal results in healthy adults and adults with Parkinson's disease.

Markerless motion capture methods are continuously in development to target limitations encountered in marker-, sensor-, or depth-based systems. Previous evaluation of the KinaTrax markerless system was limited by differences in model definitions, gait event methods, and a homogenous subject sample. The purpose of this work was to evaluate the accuracy of spatiotemporal parameters in the markerless system with an updated markerless model, coordinate- and velocity-based gait events, and subjects representing young adult, older adult, and Parkinson's disease groups. Fifty-seven subjects and 216 trials were included in this analysis. Interclass correlation coefficients showed excellent agreement between the markerless system and a marker-based reference system for all spatial parameters. Temporal variables were similar, except swing time which showed good agreement. Concordance correlation coefficients were similar with all but swing time showing moderate to almost perfect concordance. Bland-Altman bias and limits of agreement (LOA) were small and improved from previous evaluations. Parameters showed similar agreement across coordinate- and velocity-based gait methods with the latter showing generally smaller LOAs. Improvements in spatiotemporal parameters in the present evaluation was due to inclusion of keypoints at the calcanei in the markerless model. Consistency in the calcanei keypoints relative to heel marker placements may improve results further. Similar to previous work, LOAs are within boundaries to detect differences in clinical groups. Results support the use of the markerless system for estimation of spatiotemporal parameters across age and clinical groups, but caution should be taken when generalizing findings due to remaining error in kinematic gait event methods.

The Associations Between Quadriceps Tendon Graft Thickness and Isokinetic Performance.

BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) using the quadriceps tendon is an increasingly popular technique. Both partial-thickness quadriceps tendon (PT-Q) and full-thickness quadriceps tendon (FT-Q) graft depths are employed. HYPOTHESIS/PURPOSE: This study was designed to assess isokinetic peak torque, average power, and total work during knee extension in patients with FT-Q or PT-Q grafts for ACLR. We hypothesized that both groups would show lower isokinetic values for the operated side, with greater deficits in the FT-Q group than in the PT-Q group. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 26 patients who underwent ACLR with either an FT-Q or PT-Q graft were recruited between June 2021 and November 2021. Patients underwent isokinetic knee extension testing at > 1 year after surgery. Mixed repeated-measures analysis of covariance with least square difference post hoc testing was used to determine significant differences or interactions for all variables. RESULTS: Peak torque was significantly lower for the operated limb than the nonoperated limb in the FT-Q group (mean difference [MD] ± standard error [SE], -38.6 ± 8.3 Ncm [95% CI, -55.7 to -21.5 Ncm]; P < .001; d = 0.90) but not in the PT-Q group (MD ± SE, -7.3 ± 7.7 Ncm [95% CI, -23.2 to 8.5 Ncm]; P = .348; d = 0.20). Similarly, average power for the operated limb was lower than that for the nonoperated limb in the FT-Q group (MD ± SE, -53.6 ± 13.4 W [95% CI, -81.3 to -26.9 W]; P < .001; d = 0.88) but not in the PT-Q group (MD ± SE, -4.1 ± 12.4 W [95% CI, -29.8 to 21.5 W]; P = .742; d = 0.07), and total work was lower for the operated limb compared with the nonoperated limb in the FT-Q group (MD ± SE, -118.2 ± 27.1 J [95% CI, -174.3 to -62.2 J]; P < .001; d = 0.96) but not in the PT-Q group (MD ± SE, -18.3 ± 25.1 J [95% CI, -70.2 to 33.6 J]; P = .472; d = 0.15). CONCLUSION: The FT-Q group showed significant deficits in the operated limb compared with the nonoperated limb for all isokinetic variables. In contrast, no significant differences were found between the nonoperated and operated limbs for the PT-Q group.

Reliability of Gallon-Jug Shelf-Transfer Power Equations in Older Women.

ABSTRACT: Ly, A, Strand, KL, Courtney, KJ, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Reliability of gallon-jug shelf-transfer test power equations in older women. J Strength Cond Res 37(5): 1124-1130, 2023-This study examined the test-retest reliability of the gallon-jug shelf-transfer (GJST) test as a measure of upper-body functional power in older women. Although the validity of the predictive equations for power during the GJST test has been established, for the test to be viable in either a laboratory or clinical environment, between-day and within-day reliability must be established. Thirty-four independently living older women (mean ± SD : 75.0 ± 6.4 years) performed 2 sets of 3 repetitions of the GJST test on 2 days separated by at least 48 hours. Using the established predictive equations, the values for peak power and average power were then computed. Statistical analyses to assess reliability included intraclass correlation coefficient, coefficient of variation (CV), SEM , minimal detectable change (MDC), and Cronbach's α values. Furthermore, Bland-Altman plots evaluated the agreement between the tests. Intraclass correlation coefficient (>0.91, p < 0 001), CV (<8.1%), SEM (<5.94 W), MDC (<14 W), and Cronbach's α (>0.95) indicated excellent reliability. The lines of equality for all Bland-Altman plots fell within the 95% confidence interval of the mean difference, implying that there were no significant differences between tests. Furthermore, bias values were small (<11.15 W), and the limits of agreement (LOA) were within an acceptable range. Based on our statistical analyses, the GJST test is a highly reliable assessment for determining object transfer power for healthy older women.

Randomized Controlled Study of Self-Managed Music-Guided Exercise Intervention Following Intensive Care.

BACKGROUND: Patients who are discharged from the intensive care unit (ICU; termed ICU survivors) often experience persistent physical impairment. OBJECTIVE: The aim of this study was to explore the effects of a self-managed, music-guided exercise intervention on physical outcomes and adherence rates among ICU survivors. METHODS: A randomized controlled design was used. Following ICU discharge, participants admitted to the ICU for at least 5 days were randomly assigned to a music group ( n = 13) or an active control group ( n = 13). Activity counts were measured using an Actiwatch, and the physical health score was measured using the Patient-Reported Outcomes Measurement Information System global health subscale. Adherence to exercise was documented daily. Independent t -tests were used for data analysis. RESULTS: Data were analyzed for 26 participants. The mean age was 62.8 ± 13.8 years, 53.8% were male, 65.4% were White, and mean Acute Physiology and Chronic Health Evaluation severity of illness score was 59 ± 23.4. Global health physical scores were significantly higher in the music group than in the active control group. Although not significantly different, music group participants tended to be more active and had higher physical activity and adherence rates compared to those in the active control group. CONCLUSION: A self-managed, music-guided exercise intervention demonstrated positive benefits on physical outcomes. Future clinical trials with a larger sample size should be conducted to examine the effects of this tailored, cost-effective, innovative, self-managed exercise intervention among ICU survivors.

Improvement of Retinal Capillary Function After High-Speed Circuit Resistance Training in Healthy Older Adults.

BACKGROUND: To determine the retinal capillary function (RCF, the efficiency of blood flow transferring in the capillary network) and its relation to cognitive function in healthy older people without known cognitive impairment following an 8-week high-speed circuit resistance training program (HSCT). METHODS: Eleven subjects in the HSCT group and 7 age-matched nontraining controls (CON) were recruited. The HSCT group trained 3 times per week for 8 weeks, whereas CON performed no formal training. One eye of each subject from both groups was imaged at baseline and 8-week follow-up. Retinal blood flow (RBF) was measured using a retinal function imager, and retinal capillary density (RCD, expressed as fractal dimension Dbox) was measured using optical coherence tomography angiography. RCF was defined as the ratio of RBF to RCD. Cognitive function was assessed during both visits using the NIH Toolbox Fluid Cognition Battery. RESULTS: RCF was 2.07 ± 0.64 nL⋅s -1 ·Dbox -1 (mean ± SD) at baseline, and significantly increased to 2.59 ± 0.54 nL⋅s -1 ·Dbox -1 after training ( P = 0.0003) in the HSCT group, reflecting an increase of 25%. The changes of RBF were not related to the changes of RCD in the HSCT group (r = -0.18, P = 0.59). There was no significant change of RCF in the CON group ( P = 0.58). In the HSCT group, the Pattern Comparison Processing Speed Test and Fluid Cognition Composite Score were significantly increased after HSCT ( P = 0.01). Furthermore, the changes in Flanker Inhibitory Control and Attention Test (FLNK) were positively correlated to increases in RCF (r = 0.77, P = 0.005). CONCLUSIONS: This is the first prospective study to demonstrate that the increased RCF after HSCT was related to improved cognition in cognitively normal older adults.

Validity and Reliability of the Seated Medicine Ball Throw as a Measure of Upper Body Power in Older Women.

ABSTRACT: Strand, KL, Ly, AS, Barry, SS, Liscano, JA, Trebotich, TL, Martin-Diala, C, Martin, E, and Signorile, JF. Validity and reliability of the seated medicine ball throw as a measure of upper body power in older women. J Strength Cond Res 37(4): 902-908, 2023-In women, aging is associated with diminishing upper body power, which may increase the risk of falls and fall-related injury; however, the validity and reliability of clinical tests to evaluate upper body power need to be confirmed. The seated medicine ball throw (SMBT) is an upper body performance test used to monitor muscle function among older individuals. The purpose of this study was to evaluate the validity and test-retest reliability of the SMBT in older women. Thirty-five women (age = 75.15 ± 6.39 years) participated in this study. Subjects performed SMBT trials using common ball masses (SMBT 4lb and SMBT 3kg ) over 3 sessions. Familiarization with the SMBT and chest press 1 repetition maximum (CP 1RM ) was provided on the first day. On day 2, subjects repeated the tests, but data were recorded. On day 3, SMBT was retested followed by an evaluation of chest press peak power (CP PP ) values at 30-80% of CP 1RM . Significant correlations ( p ≤ 0.05) were found between the CP PP and SMBT 4lb ( r = 0.775, p < 0.001) and SMBT 3kg ( r = 0.734, p < 0.001), and SMBT distance showed expected declines with age ( r = -0.724 to -0.626, p < 0.001), demonstrating its validity. High reliability between testing days was found, and Bland-Altman plots showed few points that fell outside the limits of agreement. In conclusion, the SMBT is a valid and highly reliable tool that can be used by health professionals to monitor deficits in upper body muscular power to improve treatment protocols in older women.

Concurrent validity of artificial intelligence-based markerless motion capture for over-ground gait analysis: A study of spatiotemporal parameters.

Gait analysis is used in research and clinical environments; yet several limitations exist in current methodologies. Markerless systems, utilizing high-speed video and artificial intelligence, eliminate most limitations encountered in marker-, depth-, or inertial sensor-based systems; however, further development is needed to improve their utility and accessibility in practice. Spatiotemporal parameters from 22 young adults were estimated during over-ground gait. Nine parameters were calculated using events determined from force plate information combined with foot segment tracking and from motion of the foot relative to the sacrum using marker-based and markerless tracking. Two-way mixed effects, single measurement, absolute agreement and relative consistency interclass correlation coefficients, Bland-Altman bias and limits of agreement, and Lin's concordance correlations were used to examine the validity of parameters from markerless tracking compared to parameters calculated from gait event methods using force plates and marker-based tracking. Gait speed, stride length, step length, cycle time, and step time from the markerless system all showed strong agreement with the force plate method. Other markerless-determined parameters were not as accurate. Differences in stride width are attributable to inconsistencies in foot segment definitions between models; while differences in stance time, swing time, and double limb support time were influenced by gait event methods. Mean differences in gait parameters were smaller than meaningful clinical differences in Parkinson's disease patients and within ranges of reference values for elderly subjects. Further studies are needed to determine the validity across other patient groups, but results support the continued development of markerless systems for over-ground gait analysis.

Age-related focal thinning of the ganglion cell-inner plexiform layer in a healthy population.

Background: Given the aging of the population worldwide, to learn the underlying age-related biological phenomena is important to improve the understanding of the ageing process. Neurodegeneration is an age-associated progressive deterioration of the neuron. Retinal neurodegeneration during aging, such as the reduction in thickness of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) measured by optical coherence tomography (OCT), has been reported, but no studies have provided their specific alteration patterns with age. Therefore, this study is to provide visualization of the evolution of various tomographic intraretinal layer thicknesses during aging and to document age-related changes in focal thickness. Methods: A total 194 healthy subjects were included in this cross-sectional study. The subjects were divided into four age groups: G1, <35 years; G2, 35-49 years; G3, 50-64 years; and G4 ≥65 years. One eye of each subject was imaged using a custom-built ultrahigh-resolution optical coherence tomography (UHR-OCT). Volumetric data centered on the fovea were segmented to obtain the thickness maps of six intraretinal layers, including the macular retinal nerve fiber layer (mRNFL) and GCIPL. Results: There were alterations visualized in thickness maps in these intraretinal layers. The GCIPL showed a thickness reduction localized in the inner annulus in elder subjects (G4). Within the inner annulus, the most profound alteration in G4, an oval zone (length 0.76 mm and width 0.52 mm), appeared to be in the inferior sector about 0.61 mm below the fovea, named "A zone". The average thickness reduction of the A zone was 14.4 µm in the elderly group (G4). Age was significantly related to the GCIPL thickness of the inner annulus (ρ =-0.48; P<0.001) and of the A zone (ρ =-0.39, P<0.001). Conclusions: This is the first study to apply UHR-OCT for visualizing the age-related alteration of intraretinal layers in a general population. The most profound change of the optic nerve fiber is an oval-like focal thinning in GCIPL, which occurred in the inferior sector within the inner annulus and was strongly related to increased age.

Monitoring joint mechanics in anterior cruciate ligament reconstruction using depth sensor-driven musculoskeletal modeling and statistical parametric mapping.

The incidence of anterior cruciate ligament injury and reconstruction (ACLR) may set the stage for the development of early onset osteoarthritis in these patients. Development of accessible quantitative motion capture methodologies for recurrent monitoring of knee joint loading during daily activities following ACLR is necessary. This study aimed to compare lower extremity kinetics between ACLR affected limbs, ACLR unaffected limbs, and dominant limbs of healthy control subjects during over-ground gait and stair ascent using a single depth sensor-driven musculoskeletal modeling approach. No meaningful differences were found between groups during over-ground gait in any kinetic variables. When subjected to a stair ascent task, both ACLR limbs showed greater hip extension and internal rotation moments compared to control subjects at approximately 72-79% stance. This was coincident with greater knee flexion moments in both ALCR limbs compared to control. The absence of differences during over-ground gait but presence of compensatory strategies during stair ascent, suggests task dependent recovery in this cohort who were tested at least 1-year following surgery. Importantly, this was determined using a portable low-cost motion capture method which may be attractive to professionals in sports medicine for recurrent monitoring following ACLR.