MUSCLE - Nordic Walking in MUltiple SCLErosis (MUSCLE)

MUSCLE - Nordic and Free Walking in People With Multiple Sclerosis: Clinical-functional, Motor Control, and Gait Analysis Findings: a Randomized Controlled Multicentre Clinical Trials

The aim of the study is to analyze the effects of Nordic Walking and free walking in the clinical-functional, postural balance, motor control, muscular echographic quality, and gait analysis (pendulum gait mechanism), in people with Multiple Sclerosis.

Objective: Analyze the effects of Nordic Walking and free walking in the clinical-functional parameters, postural balance, muscular echography quality, pendulum gait mechanism, in people with Multiple sclerosis. Experimental Design: Randomized controlled multicenter clinical trial with translational study characteristics. Search Location: Exercise Research Laboratory at the School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Brazil, and University of Pavia, on Department of Public Health, Experimental Medicine and Forensic Sciences, Pavia, Italy. Participants: 60 patients from the Unified Health System (UHS) of both sexes, from 20 to 75 years old, diagnosed with multiple sclerosis, sedentary. Interventions: In this research, four groups of patients with multiple sclerosis will receive intervention during 4 months of different physical therapy programs (Nordic walking and free walking), who will receive telephone guidance for performing home-based exercises. The training programs will have a duration of 3 months and will be periodized so that the duration of the sessions is matched between them. The intensity of the interval training will be manipulated by the subjective effort scale (Borg) and by the heart rate, with predetermined series durations. All training programs will have a frequency of two sessions per week and a duration of 60 minutes. To evaluate the effects of the training, evaluations will be performed before and after the training period: 1) Basal (month 0): initial pre-training evaluation; 2) month 4: Evaluation 48h after the last training session. Outcomes: clinical-functional parameters, postural balance, muscular echography quality, pendulum gait mechanism, and biochemistry. Data Analysis: Data will be described by average values and standard deviation values. The comparisons between and within groups will be performed using a Generalized Estimating Equations (GEE) analysis, adopting a level of significance (α) of 0.05. Expected Results: The intervention groups of the Nordic walking are expected to be more effective in all outcomes analyzed, especially improving functional mobility when compared to the control group of unsupervised home exercises. In addition, it is expected that the results of the research will be expandable and the possibility of future developments in the scientific, technological, economic, social, and environmental fields and that they will be implemented in the Unified Health System (UHS).

Multiple Sclerosis, Chronic Progressive, Multiple Sclerosis, Multiple Sclerosis, Primary Progressive, Multiple Sclerosis, Secondary Progressive

Mobility, Functionality, Movement disorders, Rehabilitation, Locomotion, Gait kinematics, Electromyographic activity, Quality of life

Study Type: Interventional, Randomized controlled multicenter clinical trial In this research, four groups of patients with Parkinson's disease will receive intervention during 4 months of different physical therapy programs (Nordic walking) and free walking, who will receive telephone guidance for performing home-based exercises. The training programs will have a duration of 4 months and will be periodized so that the duration of the sessions is matched between them. The intensity of the interval training will be manipulated by the subjective effort scale (Borg) and by the heart rate, with predetermined series durations. All training programs will have a frequency of two sessions per week and a duration of 60 minutes. In order to evaluate the effects of the training, evaluations will be performed before and after the training period: 1) Basal (month 0): initial pre-training evaluation; 2) month 4: Evaluation 48h after the last training session.

The Nordic Walk program consists of 3 moments: warm-up, walk, and stretch. They will do a brief free walking warm-up for 3 minutes in the Self-selected walking speed - SSWS (3 'SSWS), then walk according to the training cycle, the intensity will be between 60 to 80% of the Heart of Ratio reserve. In addition, the intensity of the classes will be measured in each phase by the Borg Scale of Perceived Exertion.

The free walking program consists of 3 moments: warm-up, walk, and stretch. They will do a brief free walking warm-up for 3 minutes in the Self-selected walking speed - SSWS (3 'SSWS), then walk according to the training cycle, the intensity will be between 60 to 80% of the Heart of Ratio reserve. In addition, the intensity of the classes will be measured in each phase by the Borg Scale of Perceived Exertion. Intervention administered: 24 sessions will be held twice a week, with each session taking an average of 60 minutes.

The control group will receive orientation and carry out the "Health Education" program and will have a duration of 3 months.

The control group will receive orientation and carry out the "Health Education" program and will have a duration of 3 months.

Test Timed Up and Go: This test evaluates the mobility functional in three meters of self-selected speed (TUGSS) or at forced speed (TUGFS) [Time Frame: Change from baseline at 12 weeks]

The Locomotor Rehabilitation Index is a method of determining how close is the SSW compared to the Optimum Speed (Vopt).

Optimal Walking Speed (OPT) This outcome will be measure through of the registered image movement analysis using the three-dimensional motion analysis system (VICON) of the walking test on treadmill.

Quality of life (QoL) The quality of life will be estimated using the World Health Organization Quality of Life. (WHOQOL-short domains: physical, psychological, social relationships, environment, and general quality of life) and (WHOQOL-Long domains: sensory abilities, autonomy, Past. Present and Future Activities, social participation, death and dying, intimacy, and general quality of life).

This outcome will be measure for the Geriatric Depression Scale - 15 item. The scale consists of 15 dichotomous questions in which participants are asked to answer yes or no in reference to how they felt over the past week (for instance, "Do the patient feel that their life is empty?," Do the patient feel that their situation is hopeless?). Scores range from 0 to 15 with higher scores indicating more depressive symptoms.

The Expanded Disability Status Scale is the most appropriate to assess evolution and point to a new relapse. The Expanded Disability Status Scale has been the most commonly used. It has twenty items with scores ranging from 0 to 10, with the score increasing by half a point according to the patient's degree of disability, giving more focus on the patient's ability to walk (especially in scores above 4.0).

Balance Dynamics: This outcome will be evaluated using Berg Balance Scale (BBS). This scale assessment of the individual's balance in 14 situations, representative of activities of the day to day, such as: stand up, get up, walk, to lean forward, to move, to turn, among others. The maximum score of a being reached of 56 points and each item has an ordinal scale of five alternatives ranging from 0 to 4 points, according to the degree of difficulty.

Stride Length (in meters). This outcome will be measure through of the registered image movement analysis using the three-dimensional motion analysis system (VICON) of the walking test on treadmill at different speed of walking (SSWS, below and above of the SSWS), 3 minutes at each speed (in kilometers/hours).

This outcome is calculated as the inter-strides variation in terms of coefficient of variation of stride frequency.

This outcome is measure is the mean amplitude (in millivolts) of the muscles: vastus lateralis (VL), biceps femoris (BF), anterior tibial (AT) and medial gastrocnemius (MG) This outcome will be measured through Measuring the electromyographic activation during treadmill walking tests using an electromyograph. In of the walking test on treadmill at different speed of walking (SSWS, below and above of the SSWS), 3 minutes at each speed.

During the gait initiation, the investigators will evaluate the anticipatory postural adjustments. The electromyograph will be used to obtain electromyographic activity data of the spinal erector muscles, internal oblique, gluteus medius, rectus femoris, femoral biceps, medial gastrocnemius and tibialis anterior (in mV). All these parameters will be measured before and after Nordic and free walking interventions.

Muscular activation:Muscular activation during phases of the gait cycle of people with Parkinson's disease through the electromyographic evaluation of the muscles of the spinal erector, internal oblique, gluteus medius, rectus femoris, femoral biceps, anterior tibialis and medial gastrocnemius during treadmill running. All participants will walk on a treadmill at selected walking speed. To identify electromyographic activity during the different gait cycles, the electromyograph will be synchronized with VICON (Vicon Motion Capture System - Oxford - USA, 1984). All these parameters will be measured before and after Nordic and free walking interventions.

The internal work is the mechanical energy fluctuations of the movement of limbs relative to the center of body mass (Wint, in Joules). This outcome will be measured through the registered image movement analysis using the three-dimensional motion analysis system VICON of the walking test on the treadmill. All these parameters will be measured before and after Nordic and free walking interventions.

The external work is energy fluctuations of the center of body mass with respect to the external environment or surroundings (Wext, in Joules). This outcome will be measured through the registered image movement analysis using the three-dimensional motion analysis system VICON of the walking test on the treadmill. All these parameters will be measured before and after Nordic and free walking interventions.

The total mechanical work (Wtot =Wext + Wint) produced by a body during activity. These outcomes are measured by composite for:(external, internal mechanical work, in Joules). This outcome will be measured through the registered image movement analysis using the three-dimensional motion analysis system VICON of the walking test on the treadmill. All these parameters will be measured before and after Nordic and free walking interventions.

The mechanical energy exchange of the center of mass is quantified by the calculation of the percentage of reconversion of mechanical energy, called Recovery (R), which counts the form that the mechanical energy is saved through the pendulum mechanism of the locomotion. This outcome will be measured through the registered image movement analysis using the three-dimensional motion analysis system VICON of the walking test on the treadmill. This parameter will be measured before and after Nordic and free walking interventions.

The scapular girdle movement in angles will be measure, pelvic girdle in angles will be measure. The scapular girdle movement in angles will be aggregated to pelvic girdle in angles to arrive at continuous phases relation in angle. This parameter will be measured before and after Nordic and free walking interventions.

Range of motion (in degrees) of the following segments and joints: Tilt pelvic, sagittal flexion of trunk, hip flexion, knee flexion, ankle flexion, shoulder flexion, shoulder abduction, elbow flexion. All these parameters will be measured before and after Nordic and free walking interventions.

This variable will be measure by the Brunel Mood Scale (BRUMS) that was developed to provide a quick assessment of mood states adult populations. The BRUMS has been demonstrated to have Cronbach alpha values above 0.70 and is a reliable tool used to measure the mood of Brazilian athletes. The instrument consisted of 24 items and six subscales assessing mood: tension, depression, anger, vigor, fatigue and confusion. Each item was rated on a Likert scale ranging from nothing (0) to extremely (4), where the respondent indicated how they were feeling at that moment. The results were calculated using the mean of the items in each subscale.

The PSQI consists of 24 questions or items to be rated (0-3 for 20 items while 4 items are open-ended), 19 of which are self-reported and 5 of which require secondary feedback from a room or bed partner. Only the self-reported items (15 rated as 0-3 while 4 open-ended) are used for quantitative evaluation of sleep quality as perceived by the patient. The open-ended items are also finally scored as structured categorical values (rated at 0-3) as per the range of values reported for them by the patient. These 19 self-reported items are used to generate categorical scores representing the PSQI's 7 components. The individual component scores each assess a specific feature of sleep. Finally, the scores for each component are summed to get a total score, also termed the global score (range: 0 to 21). This score provides a summary of the respondent's sleep experience and quality for the past month.

Inclusion Criteria: volunteers aged over 20 years; of both sexes; with a clinical diagnosis of multiple sclerosis. Exclusion Criteria: severe heart diseases, uncontrolled hypertension, myocardial infarction within a period of less than one year, being a pacemaker; stroke or other associated neurological diseases; insanity; prostheses in the lower limbs; without ambulation conditions.

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