WHOLE-BODY VIBRATION IN PARKINSON DISEASE

EFFECTS OF WHOLE-BODY VIBRATION AT DIFFERENT FREQUENCIES ON BALANCE, GAIT, COGNITIVE FUNCTIONS, AND DUAL-TASK PERFORMANCE IN PATIENTS WITH PARKINSON'S DISEASE: A RANDOMIZED CONTROLLED TRIAL

The aim of this study is to evaluate the effects of different frequencies of Whole Body Vibration (WBV) application on balance, gait, cognitive functions, and dual-task performance in patients with Parkinson's disease.

Study Hypotheses:

H0.1 - There is no effect of different frequencies of WBV application on balance performance in patients with Parkinson's disease.

H1.1 - There is an effect of different frequencies of WBV application on balance performance in patients with Parkinson's disease.

H0.2 - There is no effect of different frequencies of WBV application on gait performance in patients with Parkinson's disease.

H1.2 - There is an effect of different frequencies of WBV application on gait performance in patients with Parkinson's disease.

H0.3 - There is no effect of different frequencies of WBV application on cognitive functions in patients with Parkinson's disease.

H1.3 - There is an effect of different frequencies of WBV application on cognitive functions in patients with Parkinson's disease.

H0.4 - There is no effect of different frequencies of WBV application on dual-task performance in patients with Parkinson's disease.

H1.4 - There is an effect of different frequencies of WBV application on dual-task performance in patients with Parkinson's disease.

H0.5 - There is no effect of different frequencies of WBV application on reaction time in patients with Parkinson's disease.

H1.5 - There is an effect of different frequencies of WBV application on reaction time in patients with Parkinson's disease.

H0.6 - There is no significant difference between medium-frequency and low-frequency WBV in terms of balance performance in patients with Parkinson's disease.

H1.6 - There is a significant difference between medium-frequency and low-frequency WBV in terms of balance performance in patients with Parkinson's disease.

H0.7 - There is no significant difference between medium-frequency and low-frequency WBV in terms of gait performance in patients with Parkinson's disease.

H1.7 - There is a significant difference between medium-frequency and low-frequency WBV in terms of gait performance in patients with Parkinson's disease.

H0.8 - There is no significant difference between medium-frequency and low-frequency WBV in terms of cognitive functions in patients with Parkinson's disease.

H1.8 - There is a significant difference between medium-frequency and low-frequency WBV in terms of cognitive functions in patients with Parkinson's disease.

H0.9 - There is no significant difference between medium-frequency and low-frequency WBV in terms of dual-task performance in patients with Parkinson's disease.

H1.9 - There is a significant difference between medium-frequency and low-frequency WBV in terms of dual-task performance in patients with Parkinson's disease.

H0.10 - There is no significant difference between medium-frequency and low-frequency WBV in terms of reaction time in patients with Parkinson's disease.

H1.10 - There is a significant difference between medium-frequency and low-frequency WBV in terms of reaction time in patients with Parkinson's disease.

Study Overview

• Status: Active, not recruiting
• Conditions: Parkinson's Disease; Cognitive Function; Gait; Reaction Time; Balance; Dual-Task Performance
• Intervention / Treatment: Behavioral: Functional Exercise Based Physiotherapy; Device: Whole Body Vibration (WBV) Therapy

Detailed Description

Parkinson's disease is the second most common neurodegenerative disorder after Alzheimer's disease and affects approximately 10 million people worldwide. Each year, more than 60,000 new cases are diagnosed in the United States alone, and this number is reported to be increasing globally. With the aging population, the prevalence of Parkinson's disease is also rising; in particular, it is reported that the prevalence among individuals over 65 years of age ranges between 1 and 2 per 1,000 people. Therefore, Parkinson's disease represents a significant health and social care burden at both individual and societal levels.

Recent studies emphasize that Parkinson's disease is a multidimensional condition and that the changes occurring during its course play a key role in disease progression.

Balance impairment and postural control deficits are among the most common problems in Parkinson's disease. Research has shown that the risk of falls is significantly increased in this patient group, with approximately 60% of patients exhibiting a tendency to fall. Balance disorders not only threaten physical safety but also restrict individuals' independence and participation in activities of daily living. Therefore, balance is considered one of the primary targets for improvement in Parkinson's rehabilitation.

Gait disturbances are another prominent functional limitation in Parkinson's disease. Reduced walking speed, shortened step length, and irregular gait rhythm lead to significant limitations in daily living activities. Loss of gait performance reduces mobility and makes independent living more difficult. For this reason, gait is considered one of the most critical targets in physiotherapy and rehabilitation programs.

Cognitive impairments are also commonly observed in patients with Parkinson's disease. These impairments typically occur in the domains of attention, executive functions, and memory. Cognitive deficits reduce independence in daily activities, limit social participation, and decrease quality of life. In addition, cognitive impairments may negatively affect the sustainability of gains achieved through motor rehabilitation.

One of the important challenges faced by Parkinson's patients is impaired dual-task performance. In daily life, individuals often need to perform both motor and cognitive tasks simultaneously. However, in Parkinson's disease, significant performance declines are observed in such tasks due to attention deficits, executive dysfunction, and motor control problems. Impairments in dual-task performance represent a critical area where cognitive and motor limitations intersect.

Another important parameter in Parkinson's disease is prolonged reaction time. It is one of the prominent effects of the disease on motor and cognitive functions. Delayed motor responses to sensory stimuli lead to reduced performance in situations requiring quick decision-making and rapid movements in daily life. Prolonged reaction times increase the risk of falls and negatively affect balance and gait performance during dual-task activities. Therefore, reaction time is considered an important functional parameter that should be assessed and improved in Parkinson's rehabilitation programs.

In recent years, Whole Body Vibration (WBV) has attracted attention in studies on non-invasive physical interventions in patients with Parkinson's disease. WBV enhances proprioceptive feedback by stimulating muscle contractions through mechanical vibration, thereby contributing to improvements in motor performance and postural control. This stimulation activates spinal reflexes, supporting rapid and coordinated muscle contractions, and also helps regulate muscle tone and postural control. In addition, WBV increases neuronal activity in cortical motor areas, strengthens neuromuscular coordination, and supports motor learning processes.

Studies have reported that WBV has positive effects on balance, postural control, and gait. However, the literature regarding its effects on cognitive functions and dual task performance remains limited. Most existing studies have been conducted with small sample sizes; there is heterogeneity in intervention protocols in terms of frequency, duration, and number of sessions, and frequencies have not been comparatively examined. Furthermore, there are no studies evaluating cognitive parameters and dual task performance in this context, which limits the generalizability of the findings. These gaps highlight the need for studies investigating the frequency dependent effects of WBV on balance, gait, cognitive functions, and dual-task performance in patients with Parkinson's disease.

The aim of study is to evaluate the effects of different frequencies of WBV on balance, gait, cognitive functions, and dual-task performance in patients with Parkinson's disease.

This study is the first to comparatively examine the frequency-dependent effects of WBV on balance, gait, cognitive functions, and dual-task performance in patients with Parkinson's disease. The findings are expected to contribute to the development of physiotherapy and rehabilitation models tailored to Parkinson's patients, focusing on targeted outcomes and individualized needs by considering the frequency dependent effects of WBV.

Study was designed as a randomized controlled, single-blind trial. In accordance with this aim, all assessments and interventions will be conducted at the Izmir Bakırçay University Physiotherapy and Rehabilitation Practice and Research Center. Patients diagnosed with Parkinson's disease who have been followed up or are currently being followed at the Neurology Department of Çiğli Training and Research Hospital, Izmir Bakırçay University, and who are referred to the Izmir Bakırçay University Physiotherapy and Rehabilitation Practice and Research Center, and who meet the inclusion and exclusion criteria, will be included in the study. Written informed consent will be obtained from all participants prior to enrollment.

In the study, participants' demographic and clinical characteristics, balance, gait, cognitive functions, dual task performance, and reaction time will be assessed using standardized evaluation tools. Demographic and clinical data will be collected using a structured assessment form and will include age, sex, height, weight, body mass index, educational status, marital status, smoking and alcohol use, medical history, and Parkinson's disease related clinical characteristics (Onset Date, Disease Duration, and Disease Stage), as well as Unified Parkinson's Disease Rating Scale (UPDRS) scores and comorbidity information. Comorbidity status will be evaluated using the Charlson Comorbidity Index. Balance will be assessed using the Mini Balance Evaluation Systems Test (Mini-BESTest), while gait performance will be measured using the 10 Meter Walk Test. Cognitive functions will be evaluated using the Verbal Fluency Test, Digit Span Test, Trail Making Test, and Stroop Color and Word Test. Dual-task performance will be assessed using the Dual Task Walking Test and the Dual-Task Timed Up and Go Test, and reaction time will be measured using the Ruler Drop Test. All assessments will be conducted according to standardized protocols, and all data will be recorded systematically.

Participants will be allocated to the intervention and control groups using a stratified randomization method to ensure that the three groups are homogeneous in terms of demographic and clinical characteristics. The intervention group will then be further randomly divided into two subgroups according to the applied frequency levels: Low Frequency (3-10 Hz) and Medium Frequency (12-20 Hz). In both groups, the interventions will be conducted for a total of 8 weeks, two days per week, in a hospital setting under appropriate safety conditions. Participants in the intervention group will perform the same functional exercise based physiotherapy program as the control group, with equal duration and intensity. In addition to the control intervention, the intervention group will receive a 20 minute Whole Body Vibration (WBV) application, which will be integrated at different frequencies (Low or Medium) depending on the assigned subgroup.

• Study Type: Interventional
• Enrollment (Actual): 66
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Izmir, Turkey (Türkiye), 35610
    • Izmir Bakircay University Cigli Training and Research Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria

• Individuals aged 30-80 years with a clinical diagnosis of Parkinson's disease. Hoehn and Yahr stages 1-3.
• Stable medical treatment (no changes in medication for the past 4 weeks).
• Willingness to participate and provision of written informed consent.
• Score of 24 or higher on the Standardized Mini Mental State Examination (SMMSE).

Exclusion Criteria

• Advanced stage Parkinson's disease (Hoehn and Yahr stage >3) or presence of severe motor complications.
• History of surgical interventions or other neurological/vestibular disorders that may affect balance and gait (E.G., stroke, epilepsy, peripheral neuropathy).
• Presence of severe cardiovascular or respiratory conditions that may affect stability (E.G., heart failure, uncontrolled hypertension, advanced COPD).
• Conditions contraindicating whole-body vibration (WBV) application (E.G., severe osteoporosis, active thrombosis).
• Psychiatric disorders or major depression that may interfere with treatment participation.
• Significant communication or language impairments affecting participation.

Withdrawal Criteria

• Voluntary withdrawal from the study.
• Development of health problems during the intervention that prevent completion of the study (E.G., unexpected acute illness or temporary medical condition).
• Changes in medication or medical status during the study that may affect participation or performance.
• Non-adherence to the protocol (attendance rate below 80% of sessions).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control Group; Participants, will receive a functional exercise based physiotherapy program in a hospital setting. The program will be supervised and conducted twice per week for 8 weeks.	Behavioral: Functional Exercise Based Physiotherapy; A supervised functional exercise-based physiotherapy program will be conducted in a hospital setting twice per week for 8 weeks.
Experimental: Low Frequency Whole Body Vibration (WBV) Group; Participants will receive a functional exercise based physiotherapy program in a hospital setting, conducted twice per week for 8 weeks. In addition, Whole Body Vibration (WBV) will be applied for 20 minutes per session at a low frequency range (3-10 Hz).	Behavioral: Functional Exercise Based Physiotherapy; A supervised functional exercise-based physiotherapy program will be conducted in a hospital setting twice per week for 8 weeks.; Device: Whole Body Vibration (WBV) Therapy; Whole Body Vibration (WBV) will be applied as an adjunct to a functional exercise based physiotherapy program. The intervention will be conducted over 8 weeks, twice per week, in a hospital setting, with each session lasting 20 minutes. WBV will be administered at different frequency ranges according to group allocation: Low Frequency (3-10 Hz) and Medium Frequency (12-20 Hz).
Experimental: Medium Frequency Whole Body Vibration (WBV) Group; Participants will receive a functional exercise based physiotherapy program in a hospital setting, conducted twice per week for 8 weeks. In addition, Whole Body Vibration (WBV) will be applied for 20 minutes per session at a medium frequency range (12-20 Hz).	Behavioral: Functional Exercise Based Physiotherapy; A supervised functional exercise-based physiotherapy program will be conducted in a hospital setting twice per week for 8 weeks.; Device: Whole Body Vibration (WBV) Therapy; Whole Body Vibration (WBV) will be applied as an adjunct to a functional exercise based physiotherapy program. The intervention will be conducted over 8 weeks, twice per week, in a hospital setting, with each session lasting 20 minutes. WBV will be administered at different frequency ranges according to group allocation: Low Frequency (3-10 Hz) and Medium Frequency (12-20 Hz).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mini Balance Evaluation Systems Test (Mini-BESTest)	Participants will be assessed while standing on a flat and firm surface. During the test, appropriate safety precautions will be taken if necessary to ensure participant safety. The assessment includes 4 subcomponents and 14 items: anticipatory postural adjustments, reactive postural control, sensory orientation, and dynamic gait. Each subcomponent represents different aspects of balance control and evaluates specific components of the postural control system. In each section of the assessment, participants will be asked to perform various functional tasks, and their performance will be observed during these tasks. The tasks include sit-to-stand and stand-to-sit transitions, standing balance, forward reach, backward stepping, standing with eyes closed, and turning while walking. Each item is scored on a 0-2 scale (0 = Severe İmpairment, 1 = Moderate İmpairment, 2 = Normal/No İmpairment), with a total score ranging from 0 to 28.	Baseline and 8 weeks
10 Meter Walk Test (10MWT)	Participants will be assessed while standing on a flat, firm, and non-slip surface. Participants will be asked to walk a 14 meter walkway, with the central 10 meter section used for timing. Walking speed will be recorded over this 10 meter distance. The test will be performed under two conditions: comfortable walking speed and maximum walking speed, with two trials for each condition. Completion time will be measured using a stopwatch, and walking speed will be calculated and expressed as meters per second (m/s) based on the average of the trials.	Baseline and 8 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Verbal Fluency Test	The test will be administered in two conditions: Semantic (Category) Fluency and Phonemic (Letter) Fluency. In the semantic fluency task, participants will be asked to generate as many words as possible belonging to a specific category (E.g., "Animals") within a given time period. In the phonemic fluency task, participants will be asked to produce as many words as possible beginning with a specific letter (E.g., "K") within a given time period. Each correct word that meets the criteria will be scored as 1 point. Repetitions, proper nouns, and responses that do not meet the specified criteria will be excluded from the scoring.	Baseline and 8 weeks
Forward-Backward Digit Span Test	Participants will be presented with sequences of numbers with increasing length and will be asked to repeat them in the correct order (Forward) and in reverse order (Backward). In both sections, the number sequences will progressively increase in length (E.G., starting with 3 digits, then 4 digits, then 5 digits, etc.). If the participant makes an error, the trial will be terminated or the sequence length will be recorded as a failure for that level. Scoring will be based on the correctly reproduced digit sequences in forward and backward conditions or the longest correctly recalled sequence. Each correct response will be scored as 1 point, and both correct and incorrect responses will be recorded.	Baseline and 8 weeks
Trail Making Test (TMT)	The test will be administered in two parts: Part A and Part B. In Part A, participants will be asked to connect numbers from 1 to 25 in ascending order as quickly as possible. In Part B, participants will be required to alternately connect numbers (1-13) and letters (A-L) in sequence (E.G., 1-A, 2-B, 3-C, etc.) as quickly and accurately as possible. For both parts, completion time, the difference between Part B and Part A (B-A), the B/A ratio, and the number of errors will be recorded.	Baseline and 8 weeks
Stroop Color and Word Test	The test will be administered in three conditions: Stroop Part 1 (Word Reading), Stroop Part 2 (Color Naming), and Stroop Part 3 (Incongruent Word-Color Condition). In Part 1, participants will be presented with a list of color words and asked to read the words aloud. In Part 2, participants will be shown colored squares and asked to name the colors. In Part 3, participants will be presented with color words printed in incongruent ink colors and asked to name the ink color rather than reading the word. For all three parts, completion time, number of correct responses, and number of incorrect responses will be recorded.	Baseline and 8 weeks
Dual-Task Gait Test	The test will be administered under three conditions: cognitive dual-task, motor dual-task, and mixed dual-task. Participants will perform the test while walking on a flat, firm, and non-slip surface. Initially, participants will be asked to walk at a normal pace. Subsequently, dual-task conditions will be introduced, requiring participants to perform an additional task while walking. In the cognitive dual-task condition, a cognitive task will be added during walking. In the motor dual-task condition, an additional motor task will be performed while walking. In the mixed dual-task condition, an additional task will be performed during turning while walking. Test duration (Seconds) will be recorded using a stopwatch. Dual-Task Cost (DTC) will be calculated using the following formula: DTC (%) = [(single-task performance - dual-task performance) / single-task performance] × 100.	Baseline and 8 weeks
Dual-Task Timed Up and Go (TUG) Test	The test will be administered under three conditions: cognitive dual-task TUG, motor dual-task TUG, and mixed dual-task TUG. Participants will perform the test while seated on a standard chair placed on a flat, firm, and non-slip surface. In the standard condition, participants will be instructed to stand up from a chair, walk a set distance, turn around, walk back, and sit down again. Subsequently, dual-task conditions will be applied by adding an additional task during the TUG procedure. In the cognitive dual-task TUG, a cognitive task will be added during the test. In the motor dual-task TUG, an additional motor task will be included. In the mixed dual-task TUG, both cognitive and motor tasks will be performed simultaneously or task difficulty will be increased.Test completion time (Seconds) will be recorded using a stopwatch. Dual-Task Cost (DTC) will be calculated using the following formula: DTC (%) = [(single-task performance - dual-task performance) / single-task perform	Baseline and 8 weeks
Ruler Drop Test	The test will be administered under three conditions: simple, selective, and dual-task. Participants will be seated with the forearm supported on a table and the elbow flexed at 90 degrees. In the simple condition, participants will be instructed to catch a falling ruler as quickly as possible when it is released. In the selective condition, participants will be required to catch the ruler only when a specific stimulus is presented. In the dual-task condition, participants will perform an additional task simultaneously while attempting to catch the ruler. The distance between the point of ruler release and the point of catch will be recorded. A total of three trials will be performed, and both the best and mean values will be recorded.	Baseline and 8 weeks

Collaborators and Investigators

• Sponsor: Izmir Bakircay University
• Investigators: Principal Investigator: Gülbin Ergin, Prof. Dr, Izmir Bakircay University

Study record dates

Study Major Dates

• Study Start (Actual): January 20, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: June 25, 2026
• First Submitted That Met QC Criteria: June 25, 2026
• First Posted (Actual): July 1, 2026

Study Record Updates

• Last Update Posted (Actual): July 1, 2026
• Last Update Submitted That Met QC Criteria: June 25, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Rehabilitation; Balance; Gait; Parkinson's Disease; Cognitive Function; Reaction Time; Neurology; Postural Control; Dual-Task Performance; Whole Body Vibration (WBV); Neuromuscular Coordination
• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease; Therapeutics
• Other Study ID Numbers: 2593; TEZ.2025.009 (Other Grant/Funding Number: Izmir Bakırçay University Scientific Research Projects Coordination Unit (BAP))

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No