Isometric vs. Dynamic Squat Pre-Loading: Acute PAPE Responses (IPP vs DPP)
2026年7月6日 更新者：Neslihan AKÇAY、Karabuk University
Acute Post-Activation Performance Responses to Isometric and Dynamic Squat Pre-Loading Protocols: A Randomized Crossover Trial
This randomized crossover study compared the acute post-activation performance responses to isometric and dynamic squat-based preconditioning protocols performed with and without electromyostimulation (EMS).
Participants completed five randomized experimental conditions: maximal voluntary isometric contraction (MVIC), dynamic contraction (DC), MVIC+EMS, DC+EMS, and EMS only (O-EMS).
Baseline and post-intervention assessments included countermovement jump (CMJ), countermovement jump with arm swing (CMJWH), zig-zag agility, and shooting speed, with post-tests conducted after a 4-minute recovery period.
Perceptual responses, including ratings of perceived exertion (RPE), perceived discomfort (RPD), and fatigue (VAS), were recorded immediately after each protocol.
All sessions were conducted between 14:00 and 16:00 under standardized conditions, with protocol order randomized and participants instructed to avoid strenuous exercise and food intake before testing.
研究概览
地位
尚未招聘
详细说明
This study aimed to compare the acute post-activation performance responses to isometric and dynamic squat-based preconditioning protocols, with and without EMS.
All testing sessions were conducted between 14:00 and 16:00 to minimize the potential effects of circadian rhythms and fatigue on performance.
The study was conducted using a randomized, crossover design.
On the remaining five experimental days, the order of the protocols was randomized for each participant using a computer-generated randomization sequence (randomizer.org)
to reduce order effects.
During the first session, participants' anthropometric measurements were recorded, their one-repetition maximum (1RM) back squat loads were determined, and they were familiarized with the equipment and testing procedures.
Participants completed five separate experimental sessions consisting of the following conditions: [A] Isometric Contraction + EMS (MVIC-EMS), [B] Dynamic Contraction + EMS (DC-EMS), [C] Dynamic Contraction (DC), [D] Isometric Contraction (MVIC), and [E] Only EMS (O-EMS).
Before each experimental protocol, baseline measurements were obtained using countermovement jump (CMJ), CMJ with hands (CMJWH), zig-zag agility test, and shooting speed assessments.
After each protocol, all tests were repeated after a 4-minute rest period (Chen et al., 2023).
Under all conditions, the electrodes were placed identically by the same experienced researcher.
Subsequently, players' shooting speeds were measured using a radar gun, with two trials performed and the highest value recorded.
Immediately after each experimental protocol, ratings of perceived exertion (RPE), perceived discomfort (RPD), and perceived fatigue level were assessed using a visual analog scale (VAS) and recorded.
Participants were instructed to refrain from food intake for 1.5 hours before testing, to avoid resistance training throughout the study period, and were verbally encouraged during all testing sessions.
研究类型
介入性
注册 (估计的)
22
阶段
- 不适用
联系人和位置
本节提供了进行研究的人员的详细联系信息，以及有关进行该研究的地点的信息。
学习联系方式
- 姓名：Neslihan Akçay, Doctorate
- 电话号码：+905468426671
- 邮箱：neslihanozcan@karabuk.edu.tr
研究联系人备份
- 姓名：Neslihan Akçay, Doctorate
学习地点
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Turkey
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Karabük、Turkey、土耳其（türkiye）、78200
- Karabuk University
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接触：
- Neslihan Akçay, Doctorate
- 电话号码：+905468426671
- 邮箱：neslihanozcan@karabuk.edu.tr
-
首席研究员：
- Neslihan Akçay, Doctorate
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副研究员：
- Cem Sofuoğlu
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副研究员：
- Wolfgang Kemmler, Prof.Dr.
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副研究员：
- Andre Filipovic, Prof.Dr.
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副研究员：
- Metehan Yana, Doctorate
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副研究员：
- Erşan Arslan, Prof.Dr.
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参与标准
研究人员寻找符合特定描述的人，称为资格标准。这些标准的一些例子是一个人的一般健康状况或先前的治疗。
资格标准
适合学习的年龄
- 成人
接受健康志愿者
是的
描述
Inclusion Criteria:
- Being healthy
- Male volleyball athletes
- Willing to maintain the intervention for all sessions
Exclusion Criteria:
- Being under 18 years old
- Having a chronic disease
- Contraindications for exercise
学习计划
本节提供研究计划的详细信息，包括研究的设计方式和研究的衡量标准。
研究是如何设计的？
设计细节
- 主要用途：治疗
- 分配：随机化
- 介入模型：交叉作业
- 屏蔽：单身的
武器和干预
参与者组/臂 |
干预/治疗 |
|---|---|
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实验性的：Condition 1
Dynamic contraction
|
Participants performed a dynamic back squat conditioning protocol on a Smith machine consisting of five sets of one repetition at 90% of one-repetition maximum (1RM), with 1 min of passive recovery between sets.
Each repetition included a controlled descent to approximately 90° of knee flexion, an explosive concentric phase, a 2-s isometric hold at full knee extension, and a slow, controlled eccentric phase (Pincivero et al.).
All repetitions were supervised to ensure proper technique.
The protocol was selected based on previous evidence supporting high-intensity resistance exercise as an effective conditioning activity for inducing PAPE responses (Dobbs et al.).
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实验性的：Condition 2
isometric contraction
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The isometric contraction protocol was conducted as described by Koźlenia and Domaradzki (2023) and Lim and Kong (2013).
Participants assumed a squat position in a squat rack with the barbell fixed in place and the knee joint positioned at approximately 90° of flexion (Profitness 1030, Türkiye).
The barbell was secured to the rack using safety pins, and participants were instructed to exert maximal force against the immovable bar to produce a MVIC.
Each contraction lasted 3 seconds, and a total of 3 repetitions were performed with 2 min of rest between repetitions (Koźlenia & Domaradzki, 2023; Lim & Kong, 2013).
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实验性的：Condition 3
Dynamic + EMS contraction
|
Participants performed a dynamic back squat conditioning protocol on a Smith machine consisting of five sets of one repetition at 90% of one-repetition maximum (1RM), with 1 min of passive recovery between sets.
In the DC-EMS condition, electromyostimulation (EMS) was applied simultaneously throughout the conditioning protocol.
Each repetition included a controlled descent to approximately 90° of knee flexion, an explosive concentric phase, a 2-s isometric hold at full knee extension, and a slow, controlled eccentric phase (Pincivero et al.).
All repetitions were supervised to ensure proper technique.
The protocol was selected based on previous evidence supporting high-intensity resistance exercise as an effective conditioning activity for inducing PAPE responses (Dobbs et al.).
|
|
实验性的：Condition 4
Isometric + EMS Contraction
|
The isometric contraction protocol was conducted as described by Koźlenia and Domaradzki (2023) and Lim and Kong (2013).
Participants assumed a squat position in a squat rack with the barbell fixed in place and the knee joint positioned at approximately 90° of flexion (Profitness 1030, Türkiye).
The barbell was secured to the rack using safety pins, and participants were instructed to exert maximal force against the immovable bar to produce an MVIC.
Each contraction lasted 3 seconds, and a total of three repetitions were performed with 2 min of rest between repetitions (Koźlenia & Domaradzki, 2023; Lim & Kong, 2013).
In the MVIC-EMS condition, electromyostimulation (EMS) was applied simultaneously during each maximal voluntary isometric contraction.
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实验性的：Condition 5
EMS contraction
|
EMS was delivered bilaterally to the quadriceps using a portable stimulator (Compex Rehab 400, Compex Medical SA, Switzerland) with a biphasic symmetrical rectangular waveform (75 Hz, 450 μs).
Four self-adhesive electrodes were placed over the vastus medialis and vastus lateralis muscles of both legs.
Participants remained seated for 10 min with the knees flexed at approximately 90° and the hips flexed at approximately 110°, while receiving EMS without performing any voluntary contractions.
Stimulation intensity was gradually increased to the highest level tolerated by each participant and maintained throughout the intervention (Paillard et al., 2008; Sofuoğlu et al., 2025).
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研究衡量的是什么？
主要结果指标
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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Countermovement Jump (CMJ) Height
大体时间：aseline and 4 minutes after each experimental condition
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Change in countermovement jump (CMJ) height (cm) from baseline to 4 minutes after each conditioning protocol, measured using a jump assessment system.
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aseline and 4 minutes after each experimental condition
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Countermovement Jump with Arm Swing (CMJWH) Height
大体时间：Baseline and 4 minutes after each experimental condition
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Change in countermovement jump with arm swing (CMJWH) height (cm) from baseline to 4 minutes after each conditioning protocol.
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Baseline and 4 minutes after each experimental condition
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Zig-Zag Agility Performance
大体时间：Baseline and 4 minutes after each experimental condition
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Change in zig-zag agility performance time (s) from baseline to 4 minutes after each conditioning protocol.
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Baseline and 4 minutes after each experimental condition
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Shooting Speed
大体时间：Baseline and 4 minutes after each experimental condition
|
Change in maximal shooting speed (km/h) from baseline to 4 minutes after each conditioning protocol, measured using a radar gun.
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Baseline and 4 minutes after each experimental condition
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次要结果测量
结果测量 |
措施说明 |
大体时间 |
|---|---|---|
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Rating of Perceived Exertion (RPE)
大体时间：Immediately after each experimental condition
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Rating of perceived exertion assessed immediately after each conditioning protocol using the Borg CR-10 scale.
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Immediately after each experimental condition
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Rating of Perceived Discomfort (RPD)
大体时间：Immediately after each experimental condition
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Rating of perceived discomfort assessed immediately after each conditioning protocol using the Borg CR-10 scale.
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Immediately after each experimental condition
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Perceived Fatigue
大体时间：Immediately after each experimental condition
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Perceived fatigue assessed immediately after each conditioning protocol using a visual analog scale (VAS).
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Immediately after each experimental condition
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合作者和调查者
在这里您可以找到参与这项研究的人员和组织。
调查人员
- 学习椅：Neslihan Akçay, Doctorate、Karabuk University
出版物和有用的链接
负责输入研究信息的人员自愿提供这些出版物。这些可能与研究有关。
一般刊物
- Keskin K, Akcay N, Ozmen T, Contarli N, Yildiz KC, Sofuoglu C, Kamis O, Rolnick N, de Queiros VS, Montoye A. Effects of different pre-exercise strategies on jumping performance in female volleyball players. J Sports Med Phys Fitness. 2025 Jan;65(1):59-68. doi: 10.23736/S0022-4707.24.16196-8. Epub 2024 Oct 3.
- Sofuoglu C, Fujita RA, Keskin K, Kamis O, Akcay N. Acute electrical muscle stimulation effects on strength and anaerobic power in soccer players. Int J Sports Med. 2025 Jun;46(7):501-509. doi: 10.1055/a-2563-9289. Epub 2025 Mar 20.
研究记录日期
这些日期跟踪向 ClinicalTrials.gov 提交研究记录和摘要结果的进度。研究记录和报告的结果由国家医学图书馆 (NLM) 审查，以确保它们在发布到公共网站之前符合特定的质量控制标准。
研究主要日期
学习开始 (估计的)
2026年8月1日
初级完成 (估计的)
2026年8月30日
研究完成 (估计的)
2026年9月5日
研究注册日期
首次提交
2026年7月6日
首先提交符合 QC 标准的
2026年7月6日
首次发布 (实际的)
2026年7月10日
研究记录更新
最后更新发布 (实际的)
2026年7月10日
上次提交的符合 QC 标准的更新
2026年7月6日
最后验证
2026年7月1日
更多信息
与本研究相关的术语
其他相关的 MeSH 术语
其他研究编号
- UKarabuk-6
计划个人参与者数据 (IPD)
计划共享个人参与者数据 (IPD)？
未定
药物和器械信息、研究文件
研究美国 FDA 监管的药品
不
研究美国 FDA 监管的设备产品
不
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