The goal of this clinical trial is to learn if a micro-dosed plyometric training program works as well as a traditional plyometric program for improving speed and explosive abilities in elite under-19 soccer players during the pre-season.

The main questions are:

1. Does micro-dosed training improve explosive and speed abilites, such as jumping and sprinting, as much as traditional training?
2. Does it improve reactivity and change-of-direction ability ?

Researchers will compare two groups:

• Traditional Training Group: 2 sessions per week, about 40 minutes each.
• Micro-dosed Group: 3-4 shorter sessions per week, about 20 minutes each. Both groups will complete the same total weekly training volume.

Participants will:

• Take part in an 8-week plyometric training program during pre-season.
• Complete performance tests (CM jump tests, a 30-meter sprint, and a 15-0-5 change-of-direction test, broad jump test, drop jump test) before and after 8-week plyometric intervention, .

This study will help coaches and players understand if shorter, more frequent plyometric training sessions can be a good alternative to traditional longer sessions when weekly training load is matched.

Inclusion Criteria:

• Active membership in a U19 elite soccer club during the intervention.
• Medical fitness to participate in plyometric training and testing.
• Attendance at ≥75% of training sessions.
• Completion of all mandatory pre- and post-tests.
• Previous experience with plyometric training and testing procedures.

Exclusion Criteria:

• Medical limitations preventing safe participation in training or testing.
• Attendance lower than 75% of scheduled intervention sessions.
• Failure to complete mandatory baseline or follow-up testing.
• Injury preventing completion of the intervention.

De-identified individual participant data (IPD), including pre- and post-intervention performance outcomes (e.g., jump height, reactive strength index, sprint performance, change-of-direction test results), will be shared. No personally identifying information will be included. Data will be shared through an open repository such as OSF (Open Science Framework) or Zenodo. The link will be provided upon availability.

Data and supporting information will be available beginning 12 months after article publication. Data will remain available for at least 5 years after publication.

Qualified researchers will be able to request access to the de-identified dataset and supporting materials by contacting the corresponding author. Access will be granted for scientific purposes only and in accordance with institutional and ethical guidelines.

Masking was not feasible due to the visible differences in training frequency and scheduling.