Neuronal Mechanisms Underlying H-Reflex Suppression During Mechanical Loading: The Role of Bone Myoregulation Reflex in Standing Humans
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 10
- 试验地点
- 1
- 主要终点
- H-reflex Amplitude
研究概览
简要总结
This study aims to investigate how standing posture and mechanical loading affect reflex responses in the lower limb. Specifically, it focuses on the H-reflex-a type of spinal cord reflex-and how it changes during quiet standing and whole-body vibration. Ten healthy adult volunteers will participate. Researchers will record electrical responses from the calf muscle (soleus) while participants stand still or are exposed to gentle vibration. The goal is to better understand how the nervous system and skeletal system interact in regulating balance and movement.
详细描述
This study investigates the neural mechanisms responsible for suppression of the H-reflex-a spinal monosynaptic reflex-during mechanical loading in the standing position. Previous research has shown that H-reflex amplitude decreases with increasing postural demand, such as during walking or standing compared to lying down. One hypothesis suggests that this suppression may be mediated not only by vestibular and cutaneous afferents, but also by a bone-derived reflex mechanism called the Bone Myoregulation Reflex (BMR).
In this study, 10 healthy adult volunteers will undergo H-reflex measurements while standing in various loading conditions, including quiet standing and during whole-body vibration (WBV). Participants will stand with one foot isolated from vibration while the other foot is on a vibrating platform. H-reflexes will be recorded from the soleus muscle using standard surface electromyography.
The primary aim is to determine whether BMR contributes to H-reflex suppression during loading. The findings may provide insight into the interaction between skeletal loading and spinal reflex modulation, with potential relevance to balance, gait, and rehabilitation science.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 20 Years 至 45 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Healthy adults aged 20 to 45 years
- •Able to stand independently for at least 10 minutes
- •No known neurological, orthopedic, or balance disorders
- •Willingness to participate and provide informed consent
排除标准
- •History of spinal cord injury, peripheral neuropathy, or muscle disease
- •Recent lower limb surgery or musculoskeletal trauma
- •Current use of medications affecting neuromuscular function
- •Pregnancy
- •Any contraindications to exposure to mechanical vibration
研究组 & 干预措施
Postural Loading and Vibration Arm
Participants in this arm will undergo a sequence of experimental conditions involving postural and mechanical loading. The protocol includes standing quietly on both feet, standing on one foot (right or left), and standing during whole-body vibration (WBV). H-reflex recordings will be obtained from the soleus muscle during each condition to assess changes in spinal reflex excitability.
干预措施: Whole-Body Vibration (WBV) (Procedure)
结局指标
主要结局
H-reflex Amplitude
时间窗: Day 1 (single-session, during each experimental condition)
The amplitude of the H-reflex recorded from the soleus muscle, evoked at 15% Mmax stimulation level, will be measured during each condition (quiet standing, one-leg stance, and whole-body vibration). The primary aim is to assess changes in spinal excitability due to mechanical loading.
次要结局
- Background EMG Activity(Day 1 (450 ms window prior to stimulation))
研究者
Selim Sezikli
Specialist in Physical Medicine and Rehabilitation
Istanbul Physical Medicine Rehabilitation Training and Research Hospital