Core Stability Training and Breaststroke Performance in University Students Learning to Swim

NCT07853235 | Completed

• 1 other identifier: CQYTXY2026011501
• Study Type: interventional
• Target: 136
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study was to find out whether adding core stability exercises to regular swimming lessons could improve breaststroke performance in university students learning to swim. These exercises involve holding the body in set positions to train muscles that help maintain posture and stability. The study included 136 university students aged 18 to 20 years. Participants were assigned by chance to one of two groups. Both groups attended the same 90-minute breaststroke lesson each week. After each lesson, one group completed 30 minutes of core stability exercises, while the other group completed 30 minutes of low-intensity stretching and relaxation activities. These additional sessions took place once a week for 14 weeks. The main comparison was the time needed to swim 25 meters using breaststroke after the training period. Other assessments measured kicking performance, the number of swimming strokes, distance traveled per stroke, and muscle endurance during exercises performed on land.

Conditions

Athletic Performance

Keywords

Swimming; Breaststroke; Core Stability; Isometric Exercise; Muscular Endurance; Novice Swimmers; University Students

Outcome Measures

Primary Outcomes (1)

• 25-Meter Breaststroke Swimming Time

  The fastest valid time, in seconds, to complete a 25-meter swim using coordinated breaststroke after the intervention. Lower values indicate better swimming performance.

  Postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

Secondary Outcomes (9)

• 25-Meter Breaststroke Kick-Only Swimming Time

  Postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

• Breaststroke Stroke Count Over 25 Meters

  Postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

• Derived Breaststroke Stroke Length

  Postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

• Wall-Sit Hold Time

  Baseline during course Weeks 1-2 and postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

• Side-Bridge Hold Time

  Baseline during course Weeks 1-2 and postintervention at course Week 16, with prespecified makeup testing at Week 17 if needed.

Study Arms (2)

Isometric Core-Stability Training

EXPERIMENTAL

Participants attended a 90-minute beginner breaststroke lesson once weekly within a 16-week university swimming course. In addition, they completed 30 minutes of isometric core-stability training immediately after each lesson during Weeks 2 through 15, for a total of 14 supplementary sessions.

Behavioral: Isometric Core-Stability Training

Stretching and Relaxation

ACTIVE COMPARATOR

Participants attended the same 90-minute beginner breaststroke lesson once weekly within a 16-week university swimming course. In addition, they completed 30 minutes of low-intensity stretching, breathing relaxation, and cool-down activities immediately after each lesson during Weeks 2 through 15, for a total of 14 time-matched supplementary sessions.

Behavioral: Low-Intensity Stretching and Relaxation

Interventions

Isometric Core-Stability Training BEHAVIORAL

A 30-minute supplementary exercise session delivered once weekly for 14 weeks during Weeks 2 through 15, immediately after the routine breaststroke lesson. The program comprised six isometric exercises: wall sit, side bridge, dead bug hold, single-leg glute bridge hold, Bulgarian split squat hold, and standard plank.

Isometric Core-Stability Training

Low-Intensity Stretching and Relaxation BEHAVIORAL

A 30-minute supplementary session of low-intensity stretching, breathing relaxation, and cool-down activities delivered once weekly for 14 weeks during Weeks 2 through 15, immediately after the routine breaststroke lesson. Session frequency and duration were matched to those of the experimental group.

Stretching and Relaxation

Eligibility Criteria

• Age: 18 Years - 20 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• University students aged 18 to 20 years enrolled in the compulsory swimming course at Chongqing College of Mobile Communication.
• Beginner breaststroke swimmers or non-swimmers with no history of systematic swimming training.
• In good health, with no disease or injury that would prevent participation in regular physical education, swimming lessons, or low- to moderate-intensity land-based isometric exercise.
• Able to understand the study information and willing to provide written informed consent.
• Available to participate in the intervention during course Weeks 2 through 15 and the scheduled assessments in Week 16.

You may not qualify if:

• Recent bone, joint, muscle, or ligament injury, or another condition that makes aquatic activity or land-based support exercises unsuitable.
• Participation in additional swimming-specific training at least twice per week, or membership on a university or departmental sports team.
• A chronic disease or acute health condition for which a physician has explicitly advised avoiding swimming or resistance/isometric exercise.

Sponsors & Collaborators

• Rongxuan Hu: lead
• Chongqing College of Mobile Communication: collaborator

Study Sites (1)

Chongqing College of Mobile Communication

Chongqing, Chongqing Municipality, 401420, China

Location

Study Officials

• Rongxuan Hu

  Chongqing College of Mobile Communication

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Outcome assessors were blinded to group assignment. Data analysts received coded datasets and remained blinded to intervention identity until the primary analyses were completed. Participants and the instructor delivering the sessions were not blinded.
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Physical Education Teacher

Model Details: Single-center, two-arm, parallel-group randomized controlled trial. Participants were individually randomized in a 1:1 ratio, stratified by sex, to supplementary isometric core-stability training or time-matched low-intensity stretching and relaxation. Both groups received the same routine breaststroke instruction.

Study Record Dates

• First Submitted: September 26, 2026
• First Posted: October 1, 2026
• Study Start: February 27, 2026
• Primary Completion: June 24, 2026
• Study Completion: June 24, 2026
• Last Updated: October 1, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ANALYTIC CODE
• Time Frame: Beginning 6 months after publication of the main study results and continuing for 5 years thereafter.
• Access Criteria: Researchers may request access through the ScienceDB dataset page by submitting a research proposal describing the study objectives, requested variables, and planned analyses. Requests will be reviewed by the study investigators and the institution for scientific merit, compatibility with participant consent, and applicable ethical and confidentiality requirements. Approved applicants must sign a data use agreement prohibiting reidentification and unauthorized redistribution. Access will be limited to the data necessary for the approved analyses.

Locations

CN (1)