ABSTRACT
La evaluación de la marcha en cinta caminadora puede resultar relevante para la toma de decisiones clínicas. No obstante, factores demográficos como la edad y el IMC pueden alterar la interpretación de los resultados. Nuestro objetivo fue obtener variables espacio- temporales, energéticas y costo de transporte durante la velocidad autoseleccionada en cinta caminadora para una muestra representativa de adultos uruguayos (n=28) y evaluar si diferentes rangos de edades e IMC pueden ser factores a tener en cuenta en pruebas clínicas donde se consideren dichas variables. Participaron 17 hombres y 11 mujeres (39,3 ± 14,8 años, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Se realizó una reconstrucción 3D del movimiento en forma sincronizada con el consumo energético. Se obtuvieron valores de referencia y luego de agrupar los participantes según su IMC y rango de edad se compararon los datos mediante test de t (p≤0.05). Los resultados revelaron discrepancias significativas en las medidas espacio-temporales y energéticas de los adultos uruguayos al caminar en cinta con respecto a la literatura. La marcha difiere entre adultos jóvenes y de mediana edad en su velocidad autoseleccionada (p=0,03), longitud de zancada (p=0,01), trabajo mecánico externo (<0,001) y recuperación de energía mecánica (0,009), destacando la importancia de considerar la edad en evaluaciones clínicas. El IMC no influyó significativamente en estas variables. Estos hallazgos subrayan la necesidad de ajustar las interpretaciones de las pruebas clínicas de la marcha sobre cinta caminadora en adultos uruguayos de mediana edad (45 a 65 años).
Treadmill gait assessment can be relevant for clinical decision-making. However, demographic factors such as age and BMI may alter result interpretation. Our aim was to obtain spatiotemporal, energetic, and cost of transport variables during self-selected treadmill walking speed for a representative sample of Uruguayan adults (n=28) and to assess if different age ranges and BMI could be factors to consider in clinical tests involving these variables. Seventeen men and eleven women participated (39.3 ± 14.8 years, 75.9 ± 12.5 kg, 1.74 ± 0.09 m, BMI 25.2 ± 4.06). A synchronized 3D motion reconstruction was performed with energy consumption. Reference values were obtained and data were compared using t-tests (p≤0.05), after grouping participants by BMI and age range. Results revealed significant discrepancies in spatiotemporal and energetic measures of Uruguayan adults walking on the treadmill, compared to the literature. Gait differed between young and middle-aged adults in their self-selected speed (p=0.03), stride length (p=0.01), external mechanical work (p<0.001), and mechanical energy recovery (0.009), emphasizing the importance of considering age in clinical evaluations. BMI did not significantly influence these variables. These findings underscore the need to adjust interpretations of treadmill gait clinical tests in middle-aged Uruguayan adults (45 to 65 years).
A avaliação da marcha na esteira pode ser relevante para a tomada de decisões clínicas. No entanto, fatores demográficos como idade e IMC podem alterar a interpretação dos resultados. Nosso objetivo foi obter variáveis espaço-temporais, energéticas e custo de transporte durante a velocidade de caminhada autoselecionada na esteira para uma amostra representativa de adultos uruguaios (n = 28) e avaliar se diferentes faixas etárias e IMC podem ser fatores a serem considerados em testes clínicos que envolvam essas variáveis. Dezessete homens e onze mulheres participaram (39,3 ± 14,8 anos, 75,9 ± 12,5 kg, 1,74 ± 0,09 m, IMC 25,2 ± 4,06). Foi realizada uma reconstrução tridimensional do movimento sincronizada com o consumo de energia. Foram obtidos valores de referência e os dados foram comparados usando testes t (p≤0,05), após agrupar os participantes por IMC e faixa etária. Os resultados revelaram discrepâncias significativas nas medidas espaço-temporais e energéticas dos adultos uruguaios ao caminhar na esteira, em comparação com a literatura. A marcha diferiu entre adultos jovens e de meia-idade em sua velocidade autoselecionada (p=0,03), comprimento da passada (p=0,01), trabalho mecânico externo (<0,001) e recuperação de energia mecânica (0,009), destacando a importância de considerar a idade em avaliações clínicas. O IMC não influenciou significativamente essas variáveis. Esses achados destacam a necessidade de ajustar as interpretações dos testes clínicos de marcha na esteira em adultos uruguaios de meia- idade (45 a 65 anos).
Subject(s)
Humans , Male , Female , Adolescent , Adult , Middle Aged , Young Adult , Body Composition/physiology , Walking/physiology , Exercise Test/statistics & numerical data , Body Mass Index , Age DistributionABSTRACT
As we age, reliance on the ankle musculature for push-off during walking reduces and increased reliance on the hip musculature is observed. It is unclear how joint pathology like osteoarthritis may affect this distal-to-proximal redistribution of propulsion. Here, we revisited a proof-of-concept study to study the effect of split-belt treadmill training, designed to reduce step length asymmetry, on forward propulsion during walking. Eleven women with hip osteoarthritis and five age-matched control participants walked on an instrumented split-belt treadmill at their preferred speed (hip osteoarthritis: 0.73 ± 0.11 m/s; controls: 0.59 ± 0.26 m/s). Women with hip osteoarthritis had less ankle power and propulsive force than controls, and greater hip contributions to forward propulsion on their involved limb. Following split-belt treadmill training, propulsive force increased on the involved limb. Five of 11 participants experienced a change in redistribution ratio that was greater than the minimal clinically meaningful difference. These "responders" had greater variability in pre-training redistribution ratio compared to non-responders. Women with hip osteoarthritis had poorer propulsive gait mechanics than controls yet split-belt treadmill training improved propulsive force. Redistribution ratio also changed in participants with high baseline variability. Our results suggest that split-belt treadmill training may be beneficial to people with hip osteoarthritis who have high variability in walking parameters. Further, the age-related shift to increased hip contributions to propulsion across populations of older adults may be due to increased variability during walking.
ABSTRACT
BACKGROUND: This study examined (i) adaptations in muscle activity following perturbation-based balance training (PBT) using treadmill belt-accelerations or PBT using walkway trips and (ii) whether adaptations during treadmill PBT transfer to a walkway trip. METHODS: Thirty-eight older people (65+ years) undertook two PBT sessions, including 11 treadmill belt-accelerations and 11 walkway trips. Surface electromyography (EMG) was measured bilaterally on the rectus femoris (RF), tibialis anterior (TA), semitendinosus (ST) and gastrocnemius medial head (GM) during the first (T1) and eleventh (T11) perturbations. Adaptations (within-subjects - 1st vs 11th perturbations for treadmill and walkway PBT) and their transfer (between-subjects - 1st walkway trip after treadmill PBT vs 1st walkway trip with no prior training) effects were examined for the EMG parameters. RESULTS: Treadmill PBT reduced post-perturbation peak muscle activation magnitude (left RF, TA, ST, right RF, ST, GM), onset latency (right TA), time to peak (right RF) and co-contraction index (knee muscles) (P < 0.05). Walkway PBT reduced post-trip onset latencies (right TA, ST), peak magnitude (left ST, right GM), time to peak (right RF, ST) and pre-perturbation muscle activity (right TA) (P < 0.05). Those who undertook treadmill PBT were not different to those without prior training during the first walkway trip (P > 0.05). CONCLUSIONS: Both treadmill and walkway PBT induced earlier initiation and peak activation of right limb muscles responsible for the first recovery step. Treadmill PBT also reduced co-contraction of the knee muscles. Adaptations in muscle activity following treadmill PBT did not transfer to a walkway trip.
ABSTRACT
Stroke rehabilitation interventions require multiple training sessions and repeated assessments to evaluate the improvements from training. Biofeedback-based treadmill training often involves 10 or more sessions to determine its effectiveness. The training and assessment process incurs time, labor, and cost to determine whether the training produces positive outcomes. Predicting the effectiveness of gait training based on baseline minimum foot clearance (MFC) data would be highly beneficial, potentially saving resources, costs, and patient time. This work proposes novel features using the Short-term Fourier Transform (STFT)-based magnitude spectrum of MFC data to predict the effectiveness of biofeedback training. This approach enables tracking non-stationary dynamics and capturing stride-to-stride MFC value fluctuations, providing a compact representation for efficient processing compared to time-domain analysis alone. The proposed STFT-based features outperform existing wavelet, histogram, and Poincaré-based features with a maximum accuracy of 95%, F1 score of 96%, sensitivity of 93.33% and specificity of 100%. The proposed features are also statistically significant (p < 0.001) compared to the descriptive statistical features extracted from the MFC series and the tone and entropy features extracted from the MFC percentage index series. The study found that short-term spectral components and the windowed mean value (DC value) possess predictive capabilities regarding the success of biofeedback training. The higher spectral amplitude and lower variance in the lower frequency zone indicate lower chances of improvement, while the lower spectral amplitude and higher variance indicate higher chances of improvement.
ABSTRACT
PURPOSE: We investigated the effects of manipulating running velocity and hypoxic exposure on vastus lateralis muscle oxygenation levels during treadmill running. METHODS: Eleven trained male distance runners performed 7 randomized runs at different velocities (8, 10, 12, 14, 16, 18, and 20 km·h-1), each lasting 45 seconds on an instrumented treadmill in normoxia (fraction of inspired oxygen [FiO2] = 20.9%), moderate hypoxia (FiO2 = 16.1%), high hypoxia (FiO2 = 14.1%), and severe hypoxia (FiO2 = 13.0%). Continuous assessment of Tissue Saturation Index (TSI) in the vastus lateralis muscle was conducted using near-infrared spectroscopy. Subsequently, changes in TSI (ΔTSI) data over the final 20 seconds of each run were compared between velocities and conditions. RESULTS: There was a significant velocity × condition interaction for ΔTSI% (P < .001, ηp2=.19), with a smaller ΔTSI% decline in normoxia compared with high hypoxia and severe hypoxia at 8 km·h-1 (g = 1.30 and 1.91, respectively), 10 km·h-1 (g = 0.75 and 1.43, respectively), and 12 km·h-1 (g = 1.47 and 1.95, respectively) (pooled values for all conditions: P < .037). The ΔTSI% decline increased with each subsequent velocity increment from 8 km·h-1 (-9.2% [3.7%]) to 20 km·h-1 (-22.5% [4.1%]) irrespective of hypoxia severity (pooled values for all conditions: P < .048). CONCLUSIONS: Running at slower velocities in conjunction with high and severe hypoxia reduces vastus lateralis muscle oxygenation levels. Muscle ΔTSI% proves to be a sensitive indicator, underscoring the potential use of near-infrared spectroscopy as a reference index of internal load during treadmill runs.
ABSTRACT
PURPOSE: Parkinson's disease creates an inability to perform previous learned autonomic tasks, such as walking, which worsens with disease progression. Recommendations to incorporate exercise at moderate to high intensities for this population has been established but there is limited knowledge about its impact on clinical based outcomes. The purpose of this research is to investigate the effectiveness of a 6-week intensity-driven walking program on clinical-based outcomes in individuals with PD. MATERIALS/METHODS: Five individuals with PD were recruited for this single-subject withdrawal design (A-B-A-B) study. 6-minute walk performance and other core neurological measures of gait were collected. Intervention phases incorporated a 30-minute individualized intensity-driven treadmill walking program practiced at 65% or more of ones maximum heart rate. Increased treadmill speed, incline, and resistance were manipulated to reach the target heart rate zone. RESULTS: 6-minute walk test within condition visual analysis demonstrated a therapeutic change during intervention phases and a countertherapeutic change during withdraw periods for all 5 individuals. An abrupt therapeutic effect was demonstrated for all individuals between conditions with the percent of nonoverlapping data ranging from 70-90%. Band method analysis revealed a range of 9-19 sessions two standard deviations above baseline mean performances for all individuals. CONCLUSION: To achieve sufficient walking performance, gait practiced at higher intensity levels may provide the optimal solution as an adjunct to standard care for individuals with PD who want to improve their walking.
Parkinson's disease creates an inability to perform previous learned autonomic tasks, such as walking, which worsens with disease progression.Exercise practiced at higher levels of intensity has been recommended to improve clinical based outcomes for the neurological population.Walking practice at higher intensity levels can provide a solution to improve gait endurance for individuals with Parkinson's disease.
ABSTRACT
BACKGROUND: Gait disturbances are exacerbated in people with Parkinson's disease (PD) during dual-task walking (DTW). Transcranial direct current stimulation (tDCS) has been shown to exert beneficial effects on gait performance and cortical excitability in PD; however, its combined effects with treadmill training (TT) remain undetermined. OBJECTIVE: To investigate the effects of tDCS followed by TT on DTW performance and cortical excitability in individuals with PD. METHODS: Thirty-four PD participants were randomized to dorsal lateral prefrontal cortex (DLPFC) tDCS and TT group (DLPFC tDCS + TT group) or sham tDCS and TT group (sham tDCS + TT group) for 50 minutes per session (20 minutes tDCS followed by 30 minutes TT), 12 sessions within 5 weeks (2-3 sessions each week). Outcome measures included cognitive dual-task walking (CDTW), motor dual-task walking (MDTW), usual walking performance, cortical excitability, functional mobility, cognitive function, and quality of life. RESULTS: The DLPFC tDCS + TT group exerted significantly greater improvement in CDTW velocity (P = .046), cadence (P = .043), and stride time (P = .041) compared to sham tDCS + TT group. In addition, DLPFC tDCS + TT group demonstrated a significant increase in resting motor threshold of stimulated hemisphere compared with sham tDCS + TT group (P = .026). However, no significant differences between groups were found in MDTW performance and other outcomes. CONCLUSION: Twelve-session DLPFC tDCS followed by TT significantly improved CDTW performance and decreased cortical excitability more than TT alone in individuals with PD. Applying DLPFC tDCS prior to TT could be suggested for gait rehabilitation in individuals with PD. CLINICAL TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trials Registry ACTRN12622000101785.
ABSTRACT
We studied the effect of N1-(2,3,4-trimethoxybenzyl)-N2-{2-[(2,3,4-trimethoxybenzyl)amino]ethyl}-1,2-ethanediamine (compound ALM-802) on the physical performance of mice after acute fatigue. The animals' performance was assessed on a treadmill. The criterion for assessing exercise tolerance was the length of the distance passed when running on a treadmill until complete fatigue. To assess the actoprotective activity of compound ALM-802, we used a method of stepwise increase in load with an initial running speed of 42 cm/sec and its subsequent increase by 5 cm/sec every 5 min. The maximum speed of movement of the treadmill belt is 77 cm/sec. Animals that received compound ALM-802 (2 mg/kg intraperitoneally), 1 day after acute fatigue, ran a distance to complete fatigue that exceeded that of control mice by 68% (387.9±60.5 and 230.6±29.6 m, respectively, p=0.023). The reference drug trimetazidine (30 mg/kg, intraperitoneally) did not have a significant effect on the distance traveled. Compound ALM-802 helps restore physical performance, i.e. exhibits significant actoprotective activity.
Subject(s)
Fatigue , Animals , Mice , Male , Fatigue/drug therapy , Exercise Tolerance/drug effects , Physical Conditioning, Animal , Physical Functional Performance , Diamines/chemistry , Diamines/pharmacologyABSTRACT
OBJECTIVE: The goal of this study was to compare the accuracy of kinematic measurements obtained using the 2-D video-based kinematic motion analysis (KMA) software Kinovea (version 0.9.5; http://www.kinovea.org) with 3-D KMA in healthy dogs. METHODS: In this prospective study, 3-D marker-based KMA (VICON-Nexus, version 2.12.1, and Procalc, version 1.6; VICON Motion Systems Ltd) was performed on healthy dogs (body weight ≥ 20 kg; height at withers > 50 cm) walking on a treadmill (study period: November 2022). Simultaneously, dogs were video recorded by 1 smartphone (iPhone SE; Apple Inc) at a 1.50-m distance perpendicular to the shoulder (60 frames per second; 1,920 X 1,080 pixels) for KMA using Kinovea. Joint angle and joint angle velocity of the shoulder, elbow, carpus, hip, stifle, and tarsus were calculated for 6 synchronized gait cycles. Each gait cycle was divided into 10 increments. The difference between 3-D KMA and Kinovea was assessed for each parameter using robust linear mixed-effects models. RESULTS: 34 dogs were included. The estimated joint angle difference between 3-D KMA and Kinovea was less than 2° for all shoulder and elbow gait cycle increments. For the carpus, hip, stifle, and tarsus, the difference was less than 2° in 9, 5, 4, and 4 out of 10 gait cycle increments, respectively. CONCLUSIONS: Kinovea provides accurate kinematic data for the shoulder and elbow of healthy dogs. Carpal, hip, stifle, and tarsal kinematics were less accurate. CLINICAL RELEVANCE: The use of Kinovea for clinical and research purposes remains limited. Future Kinovea-based studies are needed to investigate the accuracy of carpal, hip, stifle, and tarsal kinematics.
ABSTRACT
BACKGROUND: Gait training programs are commonly used to improve gait in children with cerebral palsy (CP). OBJECTIVE: To compared the effects of robotic-gait assistant training (RAGT) and conventional body weight support treadmill training (CBWSTT) on gait parameters among ambulatory children with CP. METHODS: The study is a randomized controlled trial of 36 children (17 in the RAGT group and 19 in the CBWSTT group) aged 5 to 14. Gait training involved 30-to 35-minute sessions three times per week over eight weeks. RESULTS: Mixed ANCOVA showed no main effect of time or group on all gait parameters (Pâ>â.05). Gross motor function measure dimensions D (GMFM D) and E (GMFM E) show main effects on step width. Stride length, step length, speed, swing phase, and double support phase interacted with GMFM D and E. There was a negative correlation between motor function level and the change from baseline. Children with lower motor function show a greater change from baseline. CONCLUSION: There were no significant differences between CBWSTT and RAGT for children with CP; however, with gait training interventions, the level of motor function should be considered.
Subject(s)
Cerebral Palsy , Exercise Therapy , Gait Disorders, Neurologic , Robotics , Humans , Cerebral Palsy/rehabilitation , Cerebral Palsy/physiopathology , Child , Male , Female , Robotics/methods , Adolescent , Child, Preschool , Exercise Therapy/methods , Gait Disorders, Neurologic/rehabilitation , Gait Disorders, Neurologic/etiology , Gait/physiology , Treatment OutcomeABSTRACT
To navigate complex environments, walking animals must detect and overcome unexpected perturbations. One technical challenge when investigating adaptive locomotion is measuring behavioral responses to precise perturbations during naturalistic walking; another is that manipulating neural activity in sensorimotor circuits often reduces spontaneous locomotion. To overcome these obstacles, we introduce miniature treadmill systems for coercing locomotion and tracking 3D kinematics of walking Drosophila. By systematically comparing walking in three experimental setups, we show that flies compelled to walk on the linear treadmill have similar stepping kinematics to freely walking flies, while kinematics of tethered walking flies are subtly different. Genetically silencing mechanosensory neurons altered step kinematics of flies walking on the linear treadmill across all speeds. We also discovered that flies can maintain a forward heading on a split-belt treadmill by specifically adapting the step distance of their middle legs. These findings suggest that proprioceptive feedback contributes to leg motor control irrespective of walking speed and that the fly's middle legs play a specialized role in stabilizing locomotion.
ABSTRACT
Repeated exposure to water treadmill (WT) exercise could elicit kinematic responses reflecting adaptation to WT exercise. The study's aim was to compare the responses of a group of sport horses to a standardised WT exercise test (WTSET) carried out at three time points, week 0 (n = 48), week 20 (n = 38), and week 40 (n = 29), throughout a normal training programme incorporating WT exercise. Horses were recruited from the existing client populations of two commercial water treadmill venues for the purpose of this longitudinal, observational study. Limb, back, poll, wither, and pelvic kinematics were measured during the WTSET using videography, optical motion capture, and inertial motion sensors. Forelimb and hindlimb protraction increased (p < 0.001 for both), and forelimb and hindlimb retraction decreased (p < 0.001 for both) at week 40 compared to week 0. Caudal thoracic flexion-extension and lateral bend ranges of movement were greater at week 40 compared to week 0 (p < 0.001 and p = 0.009, respectively). Increased training speed was associated with increased craniocaudal poll movement (p = 0.021), decreased forelimb protraction (p = 0.008), and increased forelimb retraction (p = 0.021). In addition to characteristic changes in kinematics due to increasing water depth, regular WT exercise resulted in kinematic adaptation to movement in water. Factors such as the frequency of WT sessions and the type of session used with respect to depth and speed were seen to influence the nature of the adaptation. The results suggest that WT exercise sessions could be designed in accordance with specific training goals when used within a normal sport horse training programme.
ABSTRACT
Post-stroke gait asymmetry leads to inefficient gait and a higher fall risk, often causing limited home and community ambulation. Two types of treadmills are typically used for training focused on symmetry: split-belt and single belt treadmills, but there is no consensus on which treadmill is superior to improve gait symmetry in individuals with stroke. To comprehensively determine which intervention is superior, we considered multiple spatial and temporal gait parameters (step length, stride time, swing time, and stance time) and their symmetries. Ten individuals with stroke underwent a single session of split-belt treadmill training and single belt treadmill training on separate days. The changes in step length, stride time, swing time, stance time and their respective symmetries were compared to investigate which training improves both spatiotemporal gait parameters and symmetries immediately after the intervention and after 5 min of rest. Both types of treadmill training immediately increased gait velocity (0.08 m/s faster) and shorter step length (4.15 cm longer). However, split-belt treadmill training was more effective at improving step length symmetry (improved by 27.3%) without sacrificing gait velocity or step length. However, this step length symmetry effect diminished after a 5-min rest period. Split-belt treadmill training may have some advantages over single belt treadmill training, when targeting step length symmetry. Future research should focus on comparing the long-term effects of these two types of training and examining the duration of the observed effects to provide clinically applicable information.
ABSTRACT
BACKGROUND: This study was designed to evaluate the effect of using maximal cadence criteria cut points established during overground and treadmill walking, on intensity outputs measured during community ambulation. The second aim was to establish the relationship between cardiovascular fitness (predicted VO2 max capacity) and community ambulation intensity performance, in typically developing individuals. RESEARCH QUESTION: What is the effect on intensity measures when using cadence cut point criteria derived from overground and treadmill walking and does predicted VO2 max correlate with exercise related community activity in a typically developing population? METHODS: A group of 37 typically developing participants between 8 and 27 years of age, underwent a graded submaximal VO2 testing protocol followed by a typical week of community ambulation, recorded with a step activity monitor. Maximum cadence criteria established during overground and treadmill walking were applied and the data were compared. The weekly step activity variables included: total steps, total ambulatory time, intensity, duration, and volume. Predicted VO2 Max was calculated, and correlations calculated to step activity outputs. RESULTS: Results showed significant differences (p<0.001) between cadence cut point criteria across all intensity measures except in the amount of time spent in the 30-60â¯% intensity category (p=0.182). Predicted VO2 max did not significantly correlate with step activity outputs related to exercise (moderate+ intensity and long duration ambulatory bouts; p>0.277). SIGNIFICANCE: This study illustrates the importance of close consideration in applying recommended cut off criteria when assessing intensity outputs from step activity data. Cadence from both overground and treadmill walking were collected in a controlled lab setting, but the influence of the treadmill mechanical and forced cadence criteria must be considered when selecting intensity cut points.
Subject(s)
Exercise Test , Oxygen Consumption , Walking , Humans , Child , Male , Female , Oxygen Consumption/physiology , Adolescent , Walking/physiology , Adult , Young Adult , Cardiorespiratory Fitness/physiologyABSTRACT
Moderate-to-vigorous-intensity physical activity decreases the risk of breast cancer. The muscle-derived cytokine (myokine), oncostatin M (OSM), has been shown to decrease breast cancer cell proliferation. We hypothesized that OSM is involved in physical activity-induced breast cancer prevention, and that OSM antibody (Anti-OSM) administration would mitigate the effect of physical activity in a rat model of mammary carcinoma. Female Sprague Dawley rats were injected with 50 mg/kg N-methyl-N-nitrosourea to induce mammary carcinogenesis. During the 20-week study, rats were exercise trained (EX) or remained sedentary (SED). Additional groups were treated with Anti-OSM antibody (SED + Anti-OSM and EX + Anti-OSM) to explore the impact of OSM blockade on tumor latency. Exercise training consisted of treadmill acclimation and progressive increases in session duration, speed, and grade, until reaching 30 min/day, 20 m/min at 15% incline. Experimentally naïve, age-matched, female rats also completed an acute exercise test (AET) with time course blood draws to evaluate OSM plasma concentrations. Relative tumor-free survival time was significantly longer in EX animals (1.36 ± 0.39) compared to SED animals (1.00 ± 0.17; p = 0.009), SED + Anti-OSM animals (0.90 ± 0.23; p = 0.019), and EX + Anti-OSM animals (0.93 ± 0.74; p = 0.004). There were no significant differences in relative tumor latency between SED, SED + Anti-OSM, or EX + Anti-OSM animals. Following the AET, OSM plasma levels trended higher compared to baseline OSM levels (p = 0.080). In conclusion, we observed that exercise-induced delay of mammary tumor development was mitigated through Anti-OSM administration. Thus, future studies of the OSM mechanism are required to lay the groundwork for developing novel chemo-prevention strategies in women who are unable or unwilling to exercise.
ABSTRACT
The purpose of this study is to evaluate the efficacy of repetitive transcranial magnetic stimulation (rTMS) combined with body weight-support treadmill training (BWSTT) for improving walking function of individuals with chronic incomplete spinal cord injury (iSCI). A 4-week, double-blinded, randomized, sham-controlled pilot study involved 12 sessions of real (10 Hz, 1800 pulses) or sham rTMS combined with BWSTT (15-20 min, moderate intensity). Walking independence was assessed using the Walking Index for Spinal Cord Injury II (WISCI-II). Lower extremity motor function (lower extremity motor score [LEMS]) and spasticity, sensory function, functional independence (Spinal Cord Injury Measure III [SCIM-III]), and quality of life were also assessed. Walking independence (WISCI-II) after the 6th session was higher in the BWSTT/rTMS real (n = 7) (median change (IQR): 3 (1.5 to 3.5)) than in the sham group (n = 8) (median change (IQR): 0 (0 to 0.25), but there was no difference between groups after 12th session (BWSTT/rTMS real median change (IQR): 4 (2 to 5); BWSSTT/rTMS sham median change (IQR): 0 (0 to 3.25). Compared to baseline, LEMS and SCIM-III mobility scores were increased after 12 sessions in the BWSTT/rTMS real but not in the sham group. Within- and between-group sensory function, functional independence, and quality of life remained similar. This preliminary result suggests that combining BWSTT with rTMS could lead to earlier gait improvement in patients with chronic iSCI.
ABSTRACT
Cerebral hemodynamics have been quantified during exercise via transcranial Doppler ultrasound, as it has high-sensitivity to movement artifacts and displays temporal superiority. Currently, limited research exists regarding how different exercise modalities and postural changes impact the cerebrovasculature across the cardiac cycle. Ten participants (4 females and 6 males) ages 20-29 completed three exercise tests (treadmill, supine, and upright cycling) to volitional fatigue. Physiological data collected included middle cerebral artery velocity (MCAv), blood pressure (BP), heart rate, and respiratory parameters. Normalized data were analyzed for variance and effect sizes were calculated to examine differences between physiological measures across the three exercise modalities. Systolic MCAv was greater during treadmill compared to supine and upright cycling (p < 0.001, (large) effect size), and greater during upright versus supine cycling (p < 0.017, (large)). Diastolic MCAv was lower during treadmill versus cycling exercise only at 60% maximal effort (p < 0.005, (moderate)) and no differences were observed between upright and supine cycling. No main effect was found for mean and diastolic BP (p > 0.05, (negligible)). Systolic BP was lower during treadmill versus supine cycling at 40% and 60% intensity (p < 0.05, (moderate-large)) and greater during supine versus upright at only 60% intensity (p < 0.003, (moderate)). The above differences were not explained by partial pressure of end-tidal carbon dioxide levels (main effect: p = 0.432). The current study demonstrates the cerebrovascular and cardiovascular systems respond heterogeneously to different exercise modalities and aspects of the cardiac cycle. As physiological data were largely similar between tests, differences associated with posture and modality are likely contributors.
ABSTRACT
AIMS: The aim of the present study was to investigate whether the predictability of fronto-parallel trunk rotations (lateral body sway) could serve as a frame of reference to monitor recovery after total knee arthroplasty (TKA). METHODS: Before surgery, 11 TKA patients were asked to perform a treadmill walking task at three different speeds. In addition, their gait abilities were scored on three standard clinical walking tests. The treadmill walking task was repeated at three different timepoints following surgery, i.e., at 3, 6 and 12 months post-TKA. The movements of the trunk were digitized with an inertial sensor to capture the amplitude and the sample entropy (SEn) of the lateral body sway that were evaluated in separate ANOVAs. RESULTS: Before surgery the TKA group showed larger body sway (P = 0.025) with smaller SEn values (P = 0.038), which both restored to levels of healthy adults in the 12 months following surgery. Systematic correlations between the SEn values and the clinical test scores were found. CONCLUSIONS: The current findings show that movement behavior of the trunk in the fronto-parallel plane was affected by knee osteoarthritis and suggest that the predictability of the lateral body sway may serve as an index of recovery after TKA.
Subject(s)
Arthroplasty, Replacement, Knee , Gait , Osteoarthritis, Knee , Postural Balance , Humans , Arthroplasty, Replacement, Knee/rehabilitation , Male , Female , Aged , Osteoarthritis, Knee/surgery , Osteoarthritis, Knee/physiopathology , Postural Balance/physiology , Gait/physiology , Middle Aged , Recovery of Function , Exercise Test/methods , Walking/physiologyABSTRACT
OBJECTIVE: In vascular dementia (VD), memory impairment caused by the damage of synaptic plasticity is the most prominent feature that afflicts patients and their families. Treadmill exercise has proven beneficial for memory by enhancing synaptic plasticity in animal models including stroke, dementia, and mental disorders. The aim of this study was to examine the effects of treadmill exercise on recognition memory and structural synaptic plasticity in VD rat model. METHODS: Male Sprague-Dawley rats were randomly assigned into four groups: control group (C group, n = 6), vascular dementia group (VD group, n = 6), treadmill exercise and vascular dementia group (Exe-VD group, n = 6), and treadmill exercise group (Exe group, n = 6). Four-week treadmill exercise was performed in the Exe-VD and Exe groups. Then, the common carotid arteries of rats in the VD and Exe-VD groups were identified to establish the VD model. Behavior tests (open-field test and novel recognition memory test) were adopted to evaluate anxiety-like behavior and recognition memory. Transmission electron microscopy and Golgi staining were performed to observe synaptic ultrastructure and spine density in the hippocampus. RESULTS: Our study demonstrated that VD rat exhibited significantly anxiety-like behavior and recognition impairment (p < .01), while treadmill exercise significantly alleviated anxiety-like behavior and improved recognition memory in VD rat (p < .01). Transmission electron microscopy revealed that hippocampal synapse numbers were significantly decreased in the VD group compared to the control group (p < .05). These alterations were reversed by treadmill exercise, and the rats exhibited healthier synaptic ultrastructure, including significantly increased synapse (p < .05). Meanwhile, golgi staining revealed that the spine numbers of the hippocampus were significantly decreased in the VD group compared to the control group (p < .05). When compared with the VD group, hippocampal spine numbers were significantly increased in the Exe-VD group (p < .05). CONCLUSION: The improvement of VD-associated recognition memory by treadmill exercises is associated with enhanced structural synaptic plasticity in VD rat model.
Subject(s)
Dementia, Vascular , Disease Models, Animal , Hippocampus , Memory Disorders , Neuronal Plasticity , Physical Conditioning, Animal , Rats, Sprague-Dawley , Recognition, Psychology , Animals , Neuronal Plasticity/physiology , Male , Hippocampus/physiopathology , Recognition, Psychology/physiology , Rats , Physical Conditioning, Animal/physiology , Memory Disorders/physiopathology , Memory Disorders/etiology , Memory Disorders/therapy , Dementia, Vascular/physiopathology , Dementia, Vascular/therapy , Synapses/physiology , Anxiety/therapy , Anxiety/physiopathologyABSTRACT
AIM: To evaluate the relationship between cardiorespiratory fitness (CRF), expressed as maximal oxygen uptake (ml.kg-1.min-1), metabolic syndrome (MetS), and high-sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation. METHODS: The relationship between CRF, MetS, and hs-CRP was examined in a cohort of 173 men and women. CRF was evaluated using a Bruce protocol treadmill test and measured as estimated maximal oxygen uptake (VO2 max). Participants' physical activity status was self-reported. Plasma hs-CRP levels were measured using a standardized immunoassay, and the diagnostic criteria for MetS were based on guidelines established by the International Diabetes Federation (IDF). RESULTS: An inverse association was observed between hs-CRP levels and estimated VO2 max (p<0.01). Additionally, hs-CRP increased linearly with the number of MetS criteria present (p<0.01), while the estimated VO2 max decreased as the number of MetS criteria increased (p<0.01). Moreover, higher estimated VO2 max correlated with increased self-reported physical activity levels (p<0.01). Notably, participants engaging in two to three hours of exercise per week had hs-CRP levels ≤2.5 mg/L (p=0.018), considered a low-to-moderate risk range. CONCLUSION: Higher CRF, reflected by an estimated VO2 max, ≥45 ml/kg/min, is associated with lower hs-CRP levels and fewer MetS criteria. Additionally, regular physical activity, corresponding to higher VO2 max, appears to reduce systemic inflammation and ameliorate MetS risk factors. These findings support the mechanisms by which improved CRF and exercise may lower the risk of cardiovascular diseases (CVD) and type 2 diabetes (T2DM).