TuJugling: Comparing Two Juggling Learning Methods in College Students (TuJugling)

TuJugling: a Cluster-randomized Cross-over Trial Comparing Two Juggling Learning Methods in College Students

This study will compare two ways of learning juggling in university students during a regular practical course: (A) juggling based on throwing the balls in the air and (B) juggling based on bouncing the balls off the floor. The study will also examine whether the order in which students learn these methods (A then B vs. B then A) influences how their performance improves over time.

Students will follow two 4-week practice periods separated by a 1-week break, and juggling performance will be assessed at three time points (baseline, after period 1, and after period 2). Performance will be scored from video recordings using anonymized study identifiers. Questionnaires about mood and flow experience will be collected at each assessment, and handgrip strength and brief computerized cognitive tasks will be assessed at baseline and the final evaluation in an exploratory manner.

The main comparison of training methods will focus on results after the first period to reduce the influence of prior practice, while results after the second period will be used to describe learning trajectories, order effects, and transfer to different execution conditions.

Study Overview

• Status: Recruiting
• Conditions: Motor Skill Learning; Juggling Performance
• Intervention / Treatment: Other: Intervention A Throwing-Based Juggling Training; Other: Intervention B Bouncing-Based Juggling Training

• Study Type: Interventional
• Enrollment (Estimated): 200
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: JAVIER Fernández-Ortega, PhD Student, Sports Science; Phone Number: +34 616 39 57 85; Email: fernandezortegaj@ugr.es
• Study Contact Backup: Name: Andrés B. Fernández-Revelles, Sport Sciences; Phone Number: +34 616 39 57 85; Email: abfr@ugr.es

Study Locations

• Spain
  • GRANADA
    • Granada, GRANADA, Spain
      • Recruiting
      • Faculty of Sports Science
      • Contact: JAVIER Fernández-Ortega, PhD Student; Phone Number: +34 616 39 57 85; Email: fernandezortegaj@ugr.es
      • Principal Investigator: Andrés Bernardo Fernández-Revelles, Sport Science

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Enrolled in the Motor Games course.
• Aged ≥18 years and able to understand and provide informed consent.
• Provide explicit agreement to participate in the study assessments.

Exclusion Criteria:

• Injury or medical condition that prevents safe participation in juggling, based on self-report prior to baseline assessment.
• Uncorrected or insufficiently corrected visual impairment that prevents seeing and tracking the balls during practice and assessments.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Intervention A: Throwing-based juggling; Intervention A consists of throwing-based juggling tasks performed according to the block-structured progression defined in the official course video tutorials	Other: Intervention A Throwing-Based Juggling Training; The program comprises two 4-week intervention periods (period 1 and period 2) separated by a 1-week separation interval. Training will be primarily self-directed and supported by standardized official video tutorials that progress from lower to higher motor complexity in structured blocks, and by a per-session log. A session will be considered valid when the student practices juggling for 20 minutes. Three frontennis balls (standard course equipment) will be used. Training may be conducted wherever the student prefers (e.g., home or university facilities). Students will advance to the next pattern when they achieve 20 consecutive successful catches in the current pattern (applicable to one-hand and two-hand patterns). Intervention A consists of throwing-based juggling tasks performed according to the block-structured progression defined in the official course video tutorials
Experimental: Intervention B consists of bouncing-based juggling tasks (ball rebounding off the floor); Intervention B consists of bouncing-based juggling tasks (ball rebounding off the floor) performed according to the block-structured progression defined in the official course video tutorials.	Other: Intervention B Bouncing-Based Juggling Training; The program comprises two 4-week intervention periods (period 1 and period 2) separated by a 1-week separation interval. Training will be primarily self-directed and supported by standardized official video tutorials that progress from lower to higher motor complexity in structured blocks, and by a per-session log. A session will be considered valid when the student practices juggling for 20 minutes. Three frontennis balls (standard course equipment) will be used. Training may be conducted wherever the student prefers (e.g., home or university facilities). Students will advance to the next pattern when they achieve 20 consecutive successful catches in the current pattern (applicable to one-hand and two-hand patterns). Intervention B consists of bouncing-based juggling tasks (ball rebounding off the floor) performed according to the block-structured progression defined in the official course video tutorials.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Juggling Performance	Juggling performance will be assessed using a study-specific standardized battery of juggling tasks. The raw outcome is the number of successful catches in a single continuous attempt, two attempts per participant. Tasks have different raw caps depending on execution type (unimanual vs bimanual). Higher scores indicate better performance. Unimanual tasks: 0-30 catches. Bimanual tasks: 0-60 catches → normalized score = raw score ÷ 2 (0-30). *Air-throw and Bounce tasks* One ball, right & left Two balls in simultaneous columns (one per hand) Two balls with alternating throws, switching hands Two-ball cycle, right & left Three-ball task using both hands *Training-specific progression patterns* RA - Active Bounce RB - Passive Bounce RC - Imperative Bounce A - Standard Cascade C - Cascade with Cycle CH - Successive Columns	Baseline and 4 weeks.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Juggling performance in different surface conditions	Juggling performance will be assessed using a study-specific standardized battery of juggling tasks. Support surface conditions: Floor (stable) and BOSU® balance trainer (unstable). The raw outcome is the number of successful catches in a single continuous attempt, two attempts per participant. Tasks have different raw caps depending on execution type (unimanual vs bimanual). Higher scores indicate better performance. Unimanual tasks: 0-30 catches. Bimanual tasks: 0-60 catches → normalized score = raw score ÷ 2 (0-30). Here the participant performs the same battery on stable and unstable condition *Air-throw and Bounce tasks* One ball, right & left Two balls in simultaneous columns (one per hand) Two balls with alternating throws, switching hands Two-ball cycle, right & left Three-ball task using both hands *Training-specific progression patterns* RA - Active Bounce RB - Passive Bounce RC - Imperative Bounce A - Standard Cascade C - Cascade with Cycle CH - Successive Columns	Baseline and 8 weeks.
Positive and Negative Affect Schedule (PANAS) - Positive Affect Subscale.	Description: The Positive Affect subscale of the PANAS questionnaire measures the degree to which a person feels enthusiastic, active, and alert. It consists of 10 items, each rated on a 5-point Likert scale (1 = very slightly or not at all; 5 = extremely). Unit of Measure: units on a scale. Scale Information: Minimum Value: 10 Maximum Value: 50 Higher scores mean a better outcome	Baseline and week 4 and week 8.
Brief Inventory of Optimal Experiences (Flow)	Flow experience during the juggling activity will be assessed using the Brief Inventory of Optimal Experiences (Flow), a validated 9-item Spanish questionnaire with a 5-point Likert scale (Strongly disagree to Strongly agree).	Baseline and week 4 and week 8.
Handgrip Strength Measured by Digital Dynamometer	Description: Handgrip strength will be assessed using a calibrated (Jamar) digital dynamometer. Participants will perform two maximum effort trials with each hand, with 60 seconds of rest between attempts. The maximum value recorded (the peak force) from the dominant hand will be used for analysis. Unit of Measure: Kilograms (kg) Scale Information: Higher scores mean a better outcome.	Baseline and week 8
Matrix Rotation Task: accuracy (%)	Visuospatial processing and mental rotation ability will be assessed using a computerized Matrix Rotation Task administered via the Psychology Experiment Building Language (PEBL) platform. Participants judge whether rotated matrices match a target configuration. The primary outcome is accuracy (% correct responses). Reaction time (median of correct trials) will also be recorded for descriptive purposes. Scores range from 0% to 100%, with higher values indicating better performance.	Baseline and week 8
Corsi Block-Tapping Test (forward): maximum span	Visuospatial working memory will be assessed using the computerized Corsi Block-Tapping Test (forward condition) administered via PEBL. Participants reproduce sequences of spatial locations in the same order presented. The primary outcome is maximum span length (longest correctly reproduced sequence). Total score may also be recorded descriptively. The span score is an integer value, with higher scores indicating better working memory performance.	Baseline and week 8
Go/No-Go Task: commission errors	Inhibitory control and sustained attention will be assessed using a computerized Go/No-Go task administered via PEBL. Participants respond to frequent Go stimuli and withhold responses to infrequent No-Go stimuli. The primary outcome is number of commission errors (responses to No-Go stimuli). Omission errors and median reaction time for correct Go trials may also be recorded descriptively. The number of commission errors ranges from 0 to the total number of No-Go trials, with lower values indicating better inhibitory control.	Baseline and week 8

Collaborators and Investigators

• Sponsor: Universidad de Granada
• Investigators: Principal Investigator: Andrés B. Fernández-Revelles, Sport Science, Universidad de Granada

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2026
• Primary Completion (Estimated): June 15, 2026
• Study Completion (Estimated): July 1, 2026

Study Registration Dates

• First Submitted: February 18, 2026
• First Submitted That Met QC Criteria: April 7, 2026
• First Posted (Actual): April 14, 2026

Study Record Updates

• Last Update Posted (Actual): April 14, 2026
• Last Update Submitted That Met QC Criteria: April 7, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Motor learning; Educational intervention; Motor performance; Juggling
• Other Study ID Numbers: #6000

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data (IPD) that underlie the results reported in future publications, including the primary outcome measures and demographic information, will be made available to qualified researchers. Data will be shared upon reasonable request to support further scientific research or meta-analysis, provided that the requestor presents a methodologically sound proposal and signs a data access agreement to ensure participant confidentiality. This access will be available starting 6 months after the primary study results are published.
• IPD Sharing Time Frame: This access will be available starting 6 months after the primary study results are published.
• IPD Sharing Access Criteria: To obtain access, requestors (researchers) must submit their proposal and a signed Data Use Agreement to the Principal Investigator at fernandezortegaj@ugr.es. The request will be reviewed by the research team to ensure ethical and scientific compliance.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE

Drug and device information, study documents

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