The Effect of BWSTT on Neuroendocrine Profile and Functional Recovery in Stroke Patients

Jagiellonian University40 enrolled

Overview

The purpose of this study is to evaluate the impact of intensive Body Weight Support Treadmill Training (BWSTT) on the neuroendocrine system and functional recovery in patients during the subacute phase of ischemic stroke. The investigators aim to determine how structured locomotor training influences the concentration of selected neurohormones and how these changes correlate with improvements in gait and balance. Participants undergo a 3-week intensive rehabilitation program, with assessments performed before and after the intervention to identify biomarkers of recovery.

A randomized controlled trial (RCT) was conducted to compare the effects of Body Weight Support Treadmill Training (BWSTT) with traditional overground gait training in patients in the subacute phase of ischemic stroke (2-6 weeks post-stroke). Both groups received 15 gait training sessions (5 sessions per week over 3 weeks) in addition to standard neurorehabilitation. Assessments were performed at baseline and after completion of the 3-week program. The analysis included: Biochemical parameters: plasma concentrations of cortisol, melatonin, serotonin, and β-endorphins. Functional variables: static and dynamic balance, mobility, risk of falls, gait speed, and walking capacity. Quality of life and the degree of disability/independence. Additionally, a long-term follow-up was conducted via telephone interviews at 6, 12, 18 months, and 5 years post-intervention to assess social participation, functional status, and long-term health outcomes (mortality and stroke recurrence). A further 10-year follow-up is planned to evaluate the long-term sustainability of the intervention effects. Experimental Group (BWSTT): Participants underwent 15 sessions (30 minutes each, 5 days/week for 3 weeks) of Body Weight Support Treadmill Training (BWSTT) using the Parestand device. A constant 25% dynamic body-weight unloading was applied. Training intensity was monitored to maintain 40-85% of Heart Rate Reserve (HRR) and a perceived exertion of \< 4 on the Modified Borg Scale (0-10). Sessions included a 3-minute warm-up and cool-down. Physical therapists provided manual facilitation of the pelvis and paretic limb as needed. In the morning (08:00-10:00), all participants received a standardized 90-minute neurorehabilitation session (NDT-Bobath/PNF) to ensure motor priming. Control Group (Overground Training): Participants underwent 15 sessions (30 minutes each, 5 days/week for 3 weeks) of traditional overground gait training. To ensure comparability, sessions were matched in duration and intensity (40-85% HRR, Modified Borg \< 4). Training focused on manual gait correction, balance exercises, and fall prevention on natural surfaces. Like the experimental group, all control participants received the same standardized 90-minute morning neurorehabilitation (NDT-Bobath/PNF).

Interventions

Body Weight Support Treadmill Training (BWSTT)DEVICE

BWSTT was performed 15 times (30 min, 5 days/week, 3 weeks) using the Parestand device with 25% dynamic body weight support. Intensity was set at 40-85% HRR (Karvonen formula) and monitored via HR, SpO2 (\>94%), and Borg scale (\<4). Sessions followed AHA/ASA guidelines: 3-min warm-up, incremental main phase, and 3-min cool-down. The physiotherapist provided manual facilitation (pelvic stabilization, knee control) and auditory stimulation (motor priming) to improve gait symmetry. Progression involved increasing speed and duration based on tolerance. Safety criteria for termination included pain, dyspnea, SpO2 \<94%, or Borg scale \>7/10. In the morning (08:00-10:00), all participants received a standardized 90-min neurorehabilitation session (NDT-Bobath/PNF) focusing on muscle tone normalization and postural control. This combined approach ensured motor priming prior to the gait-specific intervention.

Overground TrainingBEHAVIORAL

Overground gait training was performed 15 times (30 min, 5 days/week, 3 weeks). Intensity was matched to the experimental group using the Karvonen formula (40-85% HRR) and Borg scale (\<4). Sessions followed an identical structure (3-min warm-up/cool-down) and progression rules. Patients ambulated independently or with orthopedic aids. The physiotherapist supervised each session, correcting the gait pattern using neurophysiological techniques (hip approximation, manual resistance) to facilitate motor activity and ensure safety against falls. In the morning (08:00-10:00), all participants received the same standardized 90-min neurorehabilitation session (NDT-Bobath/PNF) focusing on muscle tone normalization and postural control to ensure motor priming. This baseline therapy was identical for both groups, with the gait training environment (overground vs. treadmill with BWS) being the primary differentiating factor.

Eligibility

Sex: ALLMin age: 45 YearsMax age: 85 Years

Medical Language ↔ Plain English

Inclusion Criteria: * First-ever unilateral ischemic stroke (right or left hemisphere) confirmed by MRI. * Subacute phase of stroke (between 2 and 6 weeks post-incident). * Age between 45 and 85 years. * Balance: A score of ≥ 21/56 points on the Berg Balance Scale (BBS), ensuring the ability to safely maintain a standing position. * Mobility: Baseline gait speed ≥ 0.4 m/s (classified as Limited Community Ambulation). * Permitted Aids: Use of orthopedic aids (quadripod, cane, walker) and foot stabilization (e.g., Thera-Band). * Physical Capacity: Ability to complete the 6-Minute Walk Test (6MWT) without requiring rest breaks. * Cognitive Status: MMSE score ≥ 23 (ensuring the ability to understand and follow instructions). * Informed, written patient consent provided in accordance with the Declaration of Helsinki. Exclusion Criteria: * Neurological Profile: Hemorrhagic stroke, recurrent stroke, bilateral stroke, or lesions localized in the cerebellum or brainstem. * Functional Dependence: Requirement for constant, hands-on physical assistance from third parties to maintain upright gait (despite the use of orthopedic aids). Medical Contraindications: Cardiorespiratory instability (e.g., uncontrolled hypertension, cardiac arrhythmia), recent fractures, or advanced degenerative joint changes preventing safe verticalization. * Pharmacological Interference: Use of Selective Serotonin Reuptake Inhibitors (SSRIs) or other medications significantly affecting the neuroendocrine profile (e.g., hormone replacement therapy, corticosteroids). * Communication \& Cognitive Barriers: Global or profound sensory aphasia, or severe cognitive impairment (MMSE \< 23) preventing effective cooperation. * Co-morbidities: Any neurologic (e.g., Parkinson's disease, multiple sclerosis), orthopedic, rheumatological, or internal conditions (including active malignancy, severe systemic infections, or untreated metabolic disorders) that could interfere with the intervention's safety or the integrity of hormonal and functional assays. * Consent: Withdrawal of consent or lack of voluntary, written consent to participate in the study.

Outcomes

Primary Outcomes

Neuroendocrine Profile: Plasma Cortisol Level

Blood samples (5ml) were collected between 08:00-08:30 AM from the antecubital vein into K3EDTA vacuum tubes with aprotinin (50 KIU/ml). Samples were centrifuged (10 min, 3500 rpm), partitioned into Eppendorf tubes, and stored at -80°C. Only hemolysis- and lipemia-free plasma was analyzed. Concentrations were determined via ELISA using a BioTek ELx808IU reader. Methodology: Kits utilized: Cortisol ELISA (DiaMetra, Italy). Normal range: 60-230 ng/ml. All procedures followed manufacturer protocols via Gen5 software. This is part of the exploratory assessment of the neurohormonal response to Body Weight Support Treadmill Training (BWSTT). Unit of Measure: Nanograms per milliliter

Time frame: Baseline samples were collected on Day 2 of admission, and post-intervention samples were collected during the final week (Day 21), following 15 sessions of training

Functional Walking Capacity (6-Minute Walk Test)

The 6MWT assesses functional exercise capacity and endurance. Patients are instructed to walk as far as possible for 6 minutes on a flat, hard surface at a self-selected pace. Clinical Significance: A change of 37 to 66 meters is considered a clinically significant improvement for stroke patients (Perera S. 2006). The distance covered reflects the patient's cardiovascular and muscular adaptation to physical effort in daily activities. Higher values (greater distance in meters) indicate better functional exercise capacity.

Time frame: Baseline (Day 2) and Post-intervention (Day 21, after 15 training sessions).

Short-distance Gait Speed (10-Meter Walk Test)

Measurement of walking speed at a comfortable pace. Patients walk a total of 14 meters, while the time is recorded for the central 10 meters to allow for acceleration and deceleration. Calculation: The time taken to walk the central 10 meters is recorded, and the average speed is calculated in meters per second (m/s). Clinical Significance: A change in gait speed of 0.15 - 0.25 m/s (Flansbjer U.B 2005) is considered a clinically significant improvement for stroke patients. Some studies suggest that in the subacute phase, an improvement of 0.08 - 0.14 m/s (Perera S. 2006) may already be clinically meaningful. It is assumed that achieving a speed of 0.8 m/s provides the patient with satisfactory independence (Perry J. 1995), and above 0.8 m/s - independence (Ada L. 2003). Higher values indicate better functional mobility. Unit of Measure: Meters per second

Time frame: Baseline (Day 2) and Post-intervention (Day 21, after 15 training sessions).

Neuroendocrine Profile: Plasma Serotonin Level

Blood samples (5ml) were collected between 08:00-08:30 AM from the antecubital vein into K3EDTA vacuum tubes with aprotinin (50 KIU/ml). Samples were centrifuged (10 min, 3500 rpm), partitioned into Eppendorf tubes, and stored at -80°C. Only hemolysis- and lipemia-free plasma was analyzed. Concentrations were determined via ELISA using a BioTek ELx808IU reader. Methodology: Kits utilized: Serotonin ELISA (DLD Diagnostika, Germany). Normal range: 70-270 ng/ml. All procedures followed manufacturer protocols via Gen5 software. This is part of the exploratory assessment of the neurohormonal response to Body Weight Support Treadmill Training (BWSTT). Unit of Measure: Nanograms per milliliter

Time frame: Baseline samples were collected on Day 2 of admission, and post-intervention samples were collected during the final week (Day 21), following 15 sessions of training

Neuroendocrine Profile: Plasma Melatonin Level

Blood samples (5ml) were collected between 08:00-08:30 AM from the antecubital vein into K3EDTA vacuum tubes with aprotinin (50 KIU/ml). Samples were centrifuged (10 min, 3500 rpm), partitioned into Eppendorf tubes, and stored at -80°C. Only hemolysis- and lipemia-free plasma was analyzed. Concentrations were determined via ELISA using a BioTek ELx808IU reader. Methodology: Kits utilized: Human Melatonin ELISA (BT Lab, China). Normal range: 10-40 ng/l. All procedures followed manufacturer protocols via Gen5 software. This is part of the exploratory assessment of the neurohormonal response to Body Weight Support Treadmill Training (BWSTT). Unit of Measure: Nanograms per liter

Time frame: Baseline samples were collected on Day 2 of admission, and post-intervention samples were collected during the final week (Day 21), following 15 sessions of training

Neuroendocrine Profile: Plasma β-endorphin Level

Blood samples (5ml) were collected between 08:00-08:30 AM from the antecubital vein into K3EDTA vacuum tubes with aprotinin (50 KIU/ml). Samples were centrifuged (10 min, 3500 rpm), partitioned into Eppendorf tubes, and stored at -80°C. Only hemolysis- and lipemia-free plasma was analyzed. Concentrations were determined via ELISA using a BioTek ELx808IU reader. Methodology: Kits utilized: Human β-endorphin ELISA (BT Lab, China). Normal range: 10-50 ng/l. All procedures followed manufacturer protocols via Gen5 software. This is part of the exploratory assessment of the neurohormonal response to Body Weight Support Treadmill Training (BWSTT). Unit of Measure: Nanograms per liter

Time frame: Baseline samples were collected on Day 2 of admission, and post-intervention samples were collected during the final week (Day 21), following 15 sessions of training

Secondary Outcomes

Static and Dynamic Balance (Berg Balance Scale - BBS)

The BBS is used to objectively determine the patient's ability to safely balance during a series of 14 specified tasks. Scoring: Each item is scored on a 5-point scale ranging from 0 to 4. Total scores range from 0 to 56. 0-20: wheel chair bound 21-40: walking with assistance 41-56: independent. Higher scores indicate better balance and functional mobility. Clinical Significance: For this study, the threshold for a clinically detectable change is set at a minimum of 6.9 points, following the criteria for early-stage stroke patients (Stevenson, 2001).