How does the treadmill affect gait in Parkinson’s disease?

[Abstract] Parkinson’s disease (PD) is clinically characterized by symptoms of akinesia, rigidity, and resting tremor, which are related to a dopaminergic deficiency of the nigrostriatal pathway. Disorders of gait are common symptoms of PD that affect the quality of life in these patients. One of the main focuses of physical rehabilitation in PD is to improve the gait deficits in the patients. In the last decade, a small number of studies have investigated the use of the treadmill for the rehabilitation of gait in PD patients. Although, the results of these studies are promising, the mechanisms underlying the therapeutic effect of the treadmill in PD are still largely unknown. This paper reviews 10 years of investigation of treadmill training in PD, focusing on the possible mechanisms involved in the therapeutic effect of the treadmill. Understanding these mechanisms may improve the prescription and design of physical therapy programs for PD patients.Ministerio de Ciencia e Innovación; PSI2008-03175Xunta de Galicia; 2009/00

A simple procedure using auditory stimuli to improve movement in Parkinson´s disease: a pilot study

[Abstract] It has been suggested that sequential movements in Parkinsonian patients might be improved by the effects of external rhythmic cues, either visual or acoustic, acting as a sort of timekeeper. In lin e with that idea, we have developed a portable system which allows the patient suffe ring from bradykinesia and rigidity to initiate appropriate auditory stimulation when he/she is not able to move . Here we present data from six Parkinson’s Disease (PD) patients studied with surface electromyography, while walking along an 8.5m walkway . All showed remarkable improvement in the EMG parameters studied while using the device. The results are consistent with prior reports on rhythmic auditory facilitation in Parkinson’s disease gait, and suggest that this repr esents a novel and inexpensive tool to help people afflicted by PD in daily motor performance

Efectos de un programa de intervención basado en la imposición de ritmos sonoros en pacientes con la enfermedad de Parkinson

[Resumen] En un primer estudio se evaluó en quince pacientes diagnosticados de Enfermedad de Parkinson (EP) idiopática (ocho hombres y siete mujeres, edad media 61.67 SD 5,22 y 31.07 puntos en la UPRDS) y en quince sujetos sanos (11 hombres y cuatro mujeres: edad media 63.14 SD 4.28) la marcha a su velocidad preferida y el golpeo del dedo índice a su frecuencia preferida. En ambas pruebas el grupo de EP mostró en su ejecución una estabilidad temporal (Coeficientes de Variación entre pasos y Coeficientes de Variación entre golpes) significativamente peor que el grupo control ("t"=2.059 p=0.049 para el CV de la marcha y "t"=3.218, p=0.003 para el CV del golpeo con el dedo). Posteriormente, los pacientes con EP participaron en un programa de intervención basado en la realización de diferentes tareas con presencia de ritmos sonoros. El programa constaba de 20 sesiones (5 sesiones a la semana con una duración de 1h cada sesión) y consistía básicamente en la realización de diversas tareas combinadas con la utilización de diferentes cadencias rítmicas sonoras. Finalmente y tras una nueva evaluación, los resultados indicaron que los pacientes con EP mejoraron significativamente su estabilidad temporal en ambas pruebas ("t"=2.950, p=0.011 para la marcha y "t"= 3.057, p=0.009 para el golpeo del dedo), y sus nuevos valores no diferían del grupo control ("t"=3.873, p=0.391 para la marcha y "t"=1.468, p=0.154 para el golpeo del dedo). En un segundo estudio con los datos obtenidos en una muestra seleccionada de cinco pacientes, mostramos los cambios obtenidos mediante Tomografía por Emisión de Positrones (PET) utilizando FDG. Hemos comparado los registros PET obtenidos antes y después de la intervención rítmica que se describe en el primer estudio. Los registros fueron obtenidos con cinco meses de diferencia y durante ese período los pacientes realizaron su vida normal y no sufrieron modificaciones en su medicación

Transcranial magnetic stimulation over dorsolateral prefrontal cortex in Parkinson’s disease

[Abstract] Objective Several studies have shown that repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) is effective in the treatment of depression in patients with Parkinson disease (PD). However, since research into the effect of this type of rTMS regime on motor function is limited, we studied the effect of rTMS over the DLPFC on the motor functions in PD patients. Methods Thirteen patients were randomly assigned into 2 groups, one receiving real-rTMS (90% of resting motor threshold, 10 Hz, 450 pulses-day for 10 consecutive days) over the DLPFC contralateral to the more affected side, and the other group receiving sham-rTMS. Assessment included a clinical motor evaluation using part III of the Unified Parkinson’s Disease Rating Scale (UPDRS), and several motor tasks. The UPDRS was applied before and after 10 days of rTMS. Finger tapping, reach movement, grip movement and gait were measured in each session before and after the rTMS over the 10 day period. Results Statistical analysis (ANOVA for repeated measures; group ∗ day ∗ side ∗ rTMS) only showed a significant effect for finger tapping, reach movement and gait for the factor day. No significant change was reported for the UPDRS in any group. Conclusions Application of rTMS over the DLPFC as a 10 day course had no significant effect on motor functions and clinical motor status, and the improvement in performance of motor tasks can be attributed to the effects of practice. Significance rTMS over the DLPFC did not lead to any motor improvement in PD patients

Mechanisms Involved in Treadmill Walking Improvements in Parkinson's Disease

[Abstract] Patients with Parkinson's disease (PD) improve gait after treadmill training and while they are walking over the treadmill. However, the mechanisms of these improvements have not been addressed. We designed a treadmill simulator without a belt that could move on a walkway in a constant speed, in order to explore the mechanism underlying treadmill walking improvements in PD. All subjects were tested in three different sessions (treadmill, simulatorassisted and simulatornot assisted). In each session, subjects first walked overground and then walked using the treadmill or simulator with the hands over the handrails (simulatorassisted) or with the hands free (simulatornot assisted). Step length, cadence, double support time, swing time, support time and the coefficient of variation (CV) of step time and double support time were recorded. Over the treadmill PD patients increased their step length and reduced significantly their cadence and CV of double support time in comparison with overground walking. In the simulatorassisted condition PD patients reduced significantly the CV of double support time in comparison with overground walking. With the simulatornot assisted both groups decreased their step length and increased their cadence and CV of double support time, compared with walking overground. These findings suggest that the step length improvement observed in PD patients, walking over a treadmill, is due to the proprioceptive information generated by the belt movement, since no improvement was reported when patients using a treadmill simulator.Ministerio de Ciencia e Innovación; PSI2008-03175Xunta de Galicia; 2009/00

Neuromechanical adaptation induced by jumping on an elastic surface

Jumping on an elastic surface produces a number of sensory and motor adjustments. This effect caused by jumping on the trampoline has been called “trampoline aftereffect”. The objective of the present study was to investigate the neuromuscular response related with this effect. A group of 15 subjects took part in an experimental session, where simultaneous biomechanical and electromyographic (EMG) recordings were performed during the execution of maximal countermovement jumps (CMJs) before and after jumping on an elastic surface. We assessed motor performance (leg stiffness, jump height, peak force, vertical motion of center of mass and stored and returned energy) and EMG activation patterns of the leg muscles. The results showed a significant increase (p ⩽ 0.05) of the RMS EMG of knee extensors during the eccentric phase of the jump performed immediately after the exposure phase to the elastic surface (CMJ1), and a significant increase (p ⩽ 0.05) in the levels of co-activation of the muscles crossing the ankle joint during the concentric phase of the same jump. Results related with motor performance of CMJ1 showed a significant increase in the leg stiffness (p ⩽ 0.01) due to a lower vertical motion of center of mass (CoM) (p ⩽ 0.005), a significant decrease in jump height (p ⩽ 0.01), and a significantly smaller stored and returned energy (p ⩽ 0.01). The changes found during the execution of CMJ1 may result from a mismatch between sensory feedback and the efferent copy.Actividad Física y Deport

Evaluation of the effect of training using auditory stimulation on rhythmic movement in Parkinsonian patients—a combined motor and [18F]-FDG PET study

[Abstract] Introduction: A programme of rehabilitation using auditory cues has previously been shown to decrease movement variability in the gait of Parkinsonian patients. Objective and methods: We studied the temporal variability of finger-tapping and gait in 9 patients with Parkinson's disease (PD) before and after they undertook a physical rehabilitation programme. Positron Emission Tomography (PET) using 2-deoxy-2[18F]fluoro-d-glucose (FDG) was performed in these subjects to look for changes in metabolic brain activity after completion of the rehabilitation program. Results: The reduction of variability was seen not only in gait but also other repetitive movements such as finger tapping. Furthermore, here we show differences in resting regional cerebral glucose utilisation in these patients compared to healthy controls (significant hypometabolism—p<0.001—for the PD group in the right parietal and temporal lobes, left temporal and frontal lobes and a hypermetabolism in the left cerebellum) and specific changes following the improvements in repetitive movement abilities (significant metabolic increment—p<0.001—in the PD group in the right cerebellum and in the right parietal and temporal lobes). Conclusions: Although our study does not allow us to draw firm conclusions, it provides new information on the neural basis of auditory stimulation in PD. Our results extend those from previous studies to show improvement in the temporal variability of two types of rhythmic movements after participation by PD patients in a physical rehabilitation programme, along with changes in glucose uptake in several brain areas involved in sensorimotor processing.Xunta de Galicia; PGIDIT02BTF13701P

Chronic neural adaptation induced by long-term resistance training in humans

[Abstract] While it is known that resistance training causes changes in the central nervous system (CNS) in the initial stages of training, there have been few studies of cumulative or sustained neural adaptation to resistance training beyond the initial periods. To further investigate this we compared the electromyographic (EMG) response to transcranial magnetic stimulation (TMS) during voluntary contractions of ten subjects who have been training for more than 2 years, resistance-training (RT) group, and ten subjects that have never participated in resistance training (NT). The active motor threshold for biceps brachii was obtained during voluntary elbow flexion at 10% of maximal voluntary contraction (MVC). TMS was also delivered at 100% of the maximal stimulator output while the participants exerted forces ranging from 10 to 90% of MVC. Evoked force, motor-evoked potential (MEP) amplitude and latency from biceps brachii was recorded for each condition to explore changes in corticospinal excitability. The evoked force was significantly lower in the RT group in comparison with the NT group between 30 and 70% of MVC intensity (P<0.05). At 90% of MVC, nine subjects from the RT group showed an absence in the evoked force while this occurred in only five subjects from the NT group. The MEP amplitude and latency changed significantly (P<0.001) with increasing levels of contraction, without significant difference between groups. These results indicate that changes in the CNS are sustained in the log-term practices of resistance training and permit a higher voluntary activation at several intensities of the MVC.Xunta de Galicia; PGIDIT02BTF13701P

Spatiotemporal parameters of gait during treadmill and overground walking in Parkinson's disease

[Abstract] Despite the increasing number of studies that have examined the therapeutic effect of treadmill training programs in Parkinson's disease (PD), there has been little research to evaluate the modifications of gait induced by treadmill walking. We investigated spatiotemporal differences between treadmill and overground walking in patients with PD. PD patients significantly increased their step length and step height; and reduced their cadence, step width and step width variability on the treadmill in comparison with walking overground. PD patients are able to attenuate their short shuffling steps when walking on a treadmill.Ministerio de Ciencia e Innovación; DEP2011-2246

Differences in the effects of a startle stimulus on rate of force development between resistance-trained rock climbers and untrained individuals: Evidence for reticulospinal adaptations?

The aim of the present cross-sectional study was to determine if chronic rock climbing and climbing-specific resistance training (RT) would modify the reticulospinal tract (RST) efficacy. Sixteen healthy, elite level climbers (CL; n = 16, 5 F; 29.8 ± 6.7 years) with 12 ± 7 years of climbing and climbing-specific RT experience and 15 healthy recreationally active participants (CON; n = 15, 4 F; 24.6 ± 5.9 years), volunteered for the study. We quantified RST efficacy by comparing the effects of a startle stimulus over reaction time (Rtime) and measured rate of force development (RFD) and surface electromyography (sEMG) in representative muscles during powerful hand grip contractions. Both groups performed two Rtime tasks while performing rapid, powerful gripping with the right hand (Task 1) or during 3-s-long maximal voluntary right hand grip contractions in response to an imperative visual signal alone (V), or combined with a auditory-non startle stimulus (A) or/and startling auditory stimulus (S). We also tested the reproducibility of these responses on two separate days in CON. Intersession reliability ranged from 0.34 to 0.96 for all variables. The CL versus CON was 37% stronger (p = 0.003). The S stimulus decreased Rtime and increased RFD and sEMG in both groups during both tasks (all p < 0.001). Rtime was similar between groups in all conditions. However, CL had a greater RFD from 50 to 100 ms compared with CON only after the S stimulus in both tasks (p < 0.05, d = 0.85–0.96). The data tentatively suggest that chronic rock climbing and climbing-specific RT might improve RST efficacy, by increasing RST input to the α-motoneurons13 página