Acute Effects of Static Stretching in Warm-up on Muscular Performance of Football Players
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 19
- 试验地点
- 2
- 主要终点
- Muscle Performance
研究概览
简要总结
In this study the investigators want to address acute effects of warm-up and static stretching on short-term muscular performance of football players. Static stretching exercises are often used in the first part of a training session or before a football match in order to increase sports performance and to decrease risk of injuries. Since there is a lot of scientific evidence that demonstrates static stretching can improve short-term muscle performance, the aim of researchers is to discover the size and the duration of negative effects and, additionally, whether these effects can be eliminated with activation exercises. Nineteen 14 years old football players will be included in a cross-over study design.
In the control condition the participants will perform 5 minutes of aerobic warm-up (stepping on the stair) and then 7 series of 20-seconds static stretching of quadriceps femoris, hamstrings, hip adductors and triceps surae.
Maximal power and jump height of the countermovement jump will be tested in between every series. Thus, parameters of countermovement jump will be monitored at the beginning, after warm-up, after each series of static stretching, 7.5 minutes after 7th static stretching series and 15 minutes after 7th static stretching series.
Parameters of dynamometry (relative maximal torque [Nm/kgBM] and rate of torque developement [Nm/s/kgBM] will be monitored at the beginning, after warm up, 7.5 minutes after last series of static stretching and 15 minutes after last series of static stretching.
Maximal range of motion will be monitored at the beginning, after warm up, during every series of static stretching, after last series of static stretching, 7.5 minutes after last series of static stretching and 15 minutes after last series of static stretching.
In the second condition (experimental) all the tasks are the same, the only difference is that the subjects must perform post-activation potentiation exercises after last series of static stretching.
We hypothesize that muscular performance will be impaired to a statistically significant level after 7th series of static stretching. Second hypothesis is that negative effects will not last longer than 15 minutes and the last hypothesis is that static stretching induced negative effects can be nullified with activation exercises.
详细描述
Stretching exercises are often used in warm-up to increase footballer's performance and to decrease risk of injury. The main aim of these exercises is to increase maximal active range of motion. Different types of stretching exercises are being used: ballistic, dynamic, static, eccentric flexibility training and proprioceptive neuromuscular facilitation. All of them are usually used in football training sessions in order to increase short-term range of motion and to decrease associated risk of injuries. Simic, Sarabon and Markovic (2013) in their meta-analysis reported that static stretching can have negative acute effects, which is not in line with general thinking, that static stretching in warm-up can have positive effects on sports performance.
Post-activation potentiation is a phenomenon, which is induced by loading the muscle to increase the recruitment of motor units. Since static stretching can have negative effects on muscle performance (maximal strength, power) the researchers hypothesize, that the effects can be eliminated with this type of activation exercises.
In this study the researchers want to measure acute effects of warm-up and static stretching on maximal range of motion, maximal torque and maximal rate of torque of adductors (dynamometer) and maximal power and height of countermovement jump (force plate) of football players. Since there is many scientific evidence that shows that static stretching can improve short-term muscle performance, our aim is to discover the size and the duration of negative effects and if they can be eliminated with post-activation potentiation exercises. In the cross-over study design 19 football players of age 14 will be included.
In the first condition (control) the participants will perform 5 minutes of aerobic warm-up (stepping on the stair) and then 7 series of 20-seconds bilateral static stretching of hamstrings, adductors and triceps surae (with knee extended). Quadriceps femoris will be stretched unilaterally, each muscle 20 seconds. Summary of all stretches in one series is 80 seconds. Maximal range of motion of hip abduction and hip flexion (seat and reach test) and dorsal flexion will be measured at the beginning, after warm up, during each series of static stretching, after last series of static stretching, 7.5 minutes after last series of static stretching and 15 minutes after last series of static stretching.
Maximal power [W/kg] and height [m] of the countermovement jump will be monitored with force plate at the beginning, after warm up, after each series of static stretching, 7.5 minutes after last series of static stretching and 15 minutes after last series of static stretching.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- None
入排标准
- 年龄范围
- 12 Years 至 15 Years（Child）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •football players, man
排除标准
- •injuries, last 12 months
研究组 & 干预措施
Experimental condition
7 series of static stretching will be conducted in the experimental condition. Activation exercises will be performed after 7th series of static stretching.
干预措施: Activation exercise (Other)
Experimental condition
7 series of static stretching will be conducted in the experimental condition. Activation exercises will be performed after 7th series of static stretching.
干预措施: 7 series of static stretching (Other)
Control
7 series of static stretching will be conducted in the control condition.
干预措施: 7 series of static stretching (Other)
结局指标
主要结局
Muscle Performance
时间窗: 1 week
Maximal and explosive strength of adductors, maximal power during countermovement jump
次要结局
- Jump Height(1 week)
- Rate of torque developement (Nm/s/kgBM)(1 week)
- Maximal power during countermovement jump(1 week)
- Relative maximal torque of adductors on dynamometer (Nm/kgBM)(1 week)
- Maximal range of motion (cm)(1 week)
研究者
Nejc Sarabon
Assoc. Prof. Dr. Sc.
University of Primorska