Bench Press and Machine Chest Press Elicit Distinct Acute Mechanical Responses in the Pectoralis Major: A Randomized Controlled Study
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 16
- 试验地点
- 1
- 主要终点
- Change in pectoralis major muscle stiffness measured by MyotonPRO
研究概览
简要总结
This randomized controlled study aims to compare the acute effects of bench press (BP) and machine chest press (MCP) exercises on the mechanical properties of the pectoralis major muscle in resistance-trained bodybuilders. Sixteen male athletes are randomly assigned to BP or MCP groups. Both groups perform four sets of ten repetitions at 80% of one-repetition maximum with equalized volume load. Muscle mechanical properties, including oscillation frequency, stiffness, decrement, relaxation time, and creep, are measured using MyotonPRO before and immediately after exercise. The study hypothesizes that BP will induce greater stiffness due to higher stabilization demands, whereas MCP will produce greater increases in oscillation frequency due to more isolated loading.
详细描述
Exercise selection is a key determinant of acute neuromuscular responses during resistance training. Bench press (BP) and machine chest press (MCP) are widely used exercises targeting the pectoralis major, but they differ biomechanically in stabilization demands and load distribution. While BP requires multi-joint stabilization and increased neuromuscular coordination, MCP provides a guided movement pattern that isolates the pectoralis major.
Despite similar muscle activation reported in previous electromyographic studies, the acute mechanical responses of muscle tissue to these exercises have not been directly compared. Muscle mechanical properties, including oscillation frequency, stiffness, decrement, relaxation time, and creep, provide objective insights into neuromuscular function and fatigue.
In this randomized controlled trial, sixteen male bodybuilders with at least five years of resistance training experience are assigned to BP or MCP groups. Both groups perform four sets of ten repetitions at 80% 1RM. MyotonPRO is used to assess mechanical properties of the pectoralis major before and immediately after exercise.
The primary aim is to determine whether biomechanical differences between BP and MCP produce distinct acute mechanical responses in muscle tissue.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Single (Outcomes Assessor)
盲法说明
The outcome assessor and data analyst were blinded to group allocation. Participants and care providers were not blinded due to the nature of the exercise interventions.
入排标准
- 年龄范围
- 20 Years 至 40 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Male participants
- •Aged between 20 and 40 years
- •Minimum of 5 years of regular resistance training experience
- •Competitive bodybuilding athletes
排除标准
- •History of musculoskeletal injury affecting the pectoralis major, shoulder, or upper extremity within the last 12 months
- •History of upper extremity surgery
- •Use of anabolic steroids or performance-enhancing substances within the last 12 months
研究组 & 干预措施
Bench Press Group
Participants performed a single-session resistance training protocol consisting of four sets of ten repetitions at 80% of one-repetition maximum using barbell bench press with 2-minute rest intervals between sets.
干预措施: Bench Press Exercise (Behavioral)
Machine Chest Press Group
Participants performed a single-session resistance training protocol consisting of four sets of ten repetitions at 80% of one-repetition maximum using a machine chest press with 2-minute rest intervals between sets.
干预措施: Machine Chest Press Exercise (Behavioral)
结局指标
主要结局
Change in pectoralis major muscle stiffness measured by MyotonPRO
时间窗: Baseline and immediately post-exercise (within 90 seconds)
Muscle stiffness (N/m) of the pectoralis major was measured using MyotonPRO before and immediately after the exercise protocol.
Change in oscillation frequency (muscle tone) of the pectoralis major measured by MyotonPRO
时间窗: Baseline and immediately post-exercise (within 90 seconds)
Muscle stiffness (N/m) and oscillation frequency (Hz), representing muscle tone, were measured using MyotonPRO before and immediately after the exercise protocol.
次要结局
未报告次要终点
研究者
Nihat Sarıalioğlu
Assistant Professor
Giresun University