Effect of Reverse Nordic Exercise on Vertical Jump in Youth Soccer Players

Study Overview
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Brief Summary
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BACKGROUNDː The reverse nordic hamstring exercise is developed for the eccentric work of the rectus femoris. After performing Nordic exercise protocol (its original), the relationship between increased eccentric hamstring strength, improvements in sprint capacity and reduced incidence of injuries can be confirmed. The review of evidence, led us propose the relationship and the possible benefits that could exist in the performance of four weeks of reverse nordic exercise protocol and the vertical jump, measured with countermovement jump test (CMJ) on a platform of jump. METHODSː An open randomized controlled trial was conducted, with an intervention and control group, to which they were randomly assigned. The sample was made of 19 players from the San Antonio de Murcia Catholic University Team in the youth A category, aged between 16 and 18 years old. The experimental group (n=10) performed the reverse nordic hamstring exercise protocol for four weeks, in addition to the usual training that they shared with the control group (n=9). Data collection for the CMJ test was done before starting the protocol and immediately after finishing it for all participants. Statistical analysis was carried out with the SPSS program.

Official Title
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Effect of Reverse Nordic Exercise on Vertical Jump in Youth Soccer Players: Randomized Controlled Trial

Conditions
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Strength

Intervention / Treatment
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* Procedure: Nordic Reverse Protocol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Between 16 and 18 years old Soccer Players Exclusion Criteria: Pathologies or Musculoskeletal Injuries in the last 6 months Surgical Interventions in the lower extremities in the last 6 months

Ages Eligible for Study
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Minimum Age: 16 Years
Maximum Age: 18 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Randomized Controlled Trial
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Nordic Reverse Protocol<br>The intervention group performed the reverse Nordic exercise or quadriceps drop protocol for four weeks in their training sessions. Participants assigned to the intervention group warm up for approximately 15/20 minutes, consisting of five minutes of continuous running at low speed (approximately 10 km/h), followed by 3 minutes of stretching the lower extremities and three separate progressive sprints. between them with two minutes of rest to finish, then they will carry out the corresponding series and repetitions of the protocol and continue with their usual training. | Procedure: Nordic Reverse Protocol<br>* The participant begins on their knees, with the trunk upright and fully aligned. At this moment, the soccer player slowly leans back, maintaining the starting position by means of a controlled flexion of the knees. This fall is executed at the lowest speed possible to maximize muscle load in the eccentric phase and reach the point of maximum flexion.<br>|
| No Intervention: Usual Training Sessions<br>The control group did not have any intervention, the participants randomly assigned to this group continued with their usual training sessions. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Flight Time | Chronojump Boscosystem® contact platform (Barcelona), to measure the vertical jump (CMJ and Abalakov) and the Chronojump Boscosystem® Software version 1.7.1 | It was performed 3 days after completing the 4-week reverse Nordic exercise protocol. | 
| Jump Height | Chronojump Boscosystem® contact platform (Barcelona), to measure the vertical jump (CMJ and Abalakov) and the Chronojump Boscosystem® Software version 1.7.1 | It was performed 3 days after completing the 4-week reverse Nordic exercise protocol. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Soccer, Eccentric Force, Quadriceps, Reverse Nordic Hamstring Exercise, Vertical Jump