Effect of Reverse Nordic Exercise on Countermovement in Youth Soccer Players

Preliminary Effects of Reverse Nordic Exercise on Countermovement Jump Performance in Youth Soccer Players: A Pilot Randomized Controlled Trial

This pilot randomized controlled trial aims to evaluate the preliminary effects and feasibility of a four-week Reverse Nordic Exercise program on countermovement jump performance in youth soccer players during the competitive season. Participants are randomly allocated to either a Reverse Nordic Exercise group, which performs a progressive eccentric quadriceps training program in addition to regular soccer training, or a control group that continues usual training. Countermovement jump performance is assessed before and after the intervention to estimate potential treatment effects and inform the design of a future fully powered randomized controlled trial.

Study Overview

• Status: Completed
• Conditions: Strength Training Effects
• Intervention / Treatment: Procedure: Nordic Reverse Protocol

• Study Type: Interventional
• Enrollment (Actual): 18
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Spain
  • Murcia
    • Murcia, Murcia, Spain, 30107
      • Universidad Católica San Antonio de Murcia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: Yes

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental: Nordic Reverse Protocol; 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; 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.
No Intervention: No Intervention : Usual Training Sessions; 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?

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.

Collaborators and Investigators

• Sponsor: Universidad de Murcia

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2021
• Primary Completion (Actual): March 4, 2022
• Study Completion (Actual): April 4, 2022

Study Registration Dates

• First Submitted: July 19, 2026
• First Submitted That Met QC Criteria: July 22, 2026
• First Posted (Actual): July 27, 2026

Study Record Updates

• Last Update Posted (Actual): July 27, 2026
• Last Update Submitted That Met QC Criteria: July 22, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: Soccer; eccentric training; Countermovement jump; Reverse Nordic Exercise
• Other Study ID Numbers: CE012205

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No