Effects of spinal manipulation on lower limb strength and endurance in adolescent athletes: a randomized controlled trial
| ISRCTN | ISRCTN16848241 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN16848241 |
- Submission date
- 25/07/2025
- Registration date
- 28/07/2025
- Last edited
- 28/07/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Ongoing
- Condition category
- Musculoskeletal Diseases
Plain English summary of protocol
Background and study aims
This study is looking at whether a chiropractic technique called spinal manipulation can help teenage athletes get stronger and perform better. Many young athletes have small joint or muscle issues that might affect how well they move or increase their risk of injury. The researchers want to see if spinal manipulation can support strength development during a short training program.
Who can participate?
Healthy teenage athletes aged 15 to 17 years can take part, as long as they’ve been cleared by a doctor for physical activity and haven’t had spinal manipulation before.
What does the study involve?
Participants will be randomly placed into one of two groups. Both groups will do the same four-week strength training program. One group will also receive spinal manipulation once a week. Before and after the program, everyone will do tests to measure leg strength, balance, and how confident and tired they feel during exercise.
What are the possible benefits and risks of participating?
Taking part might help improve strength, balance, and body awareness. The risks are very low and similar to those of regular exercise. Spinal manipulation is commonly used and is considered safe for healthy teens when done by trained professionals.
Where is the study run from?
Caozhou Wu School in Heze, Shandong Province, China.
When is the study starting and how long is it expected to run for?
Recruitment began in August 2025, and the researchers expect to finish collecting data by September 2025.
Who is funding the study?
Investigator initiated and funded
Who is the main contact?
Qian Zhang, lemon28@icloud.com
Contact information
Scientific, Principal Investigator
Hui Long Guan, Xin Long Cheng
Beijing
100096
China
 ORCID ID |
0000-0002-4493-3916 |
|---|---|
| Phone | +86 15178028548 |
| qian.zhang@palmer.edu |
Public
No.48 Information Rd
Beijing
100084
China
| Phone | +86 13733112288 |
|---|---|
| zhangxuyang2456@126.com |
Study information
| Study design | Prospective randomized controlled trial with two parallel groups |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised parallel trial |
| Study setting(s) | Built environment/local authority, Community |
| Study type | Prevention, Quality of life, Treatment |
| Participant information sheet | 47728 Participant Information Sheet.pdf |
| Scientific title | A randomized controlled trial evaluating the effects of spinal manipulation on lower extremity strength and functional performance in adolescent athletes |
| Study objectives | To evaluate the effects of spinal manipulation on lower extremity strength and functional performance in adolescent athletes. The study aims to determine whether spinal manipulation can enhance lower-limb power, endurance, and agility when compared to a control group undergoing physical training alone. |
| Ethics approval(s) |
Approved 11/07/2025, Sports Science Experiment Ethics Committee of Beijing Sport University (No. 48, Information Road, Haidian District, Beijing, 100084, China; +86 10-62989306; bsulb@bsu.edu.cn), ref: 2025325H |
| Health condition(s) or problem(s) studied | Musculoskeletal performance deficits, including suboptimal lower-limb strength and endurance, in adolescent athletes |
| Intervention | The experimental group received lumbopelvic spinal manipulation (SM) once a week for four weeks, targeting segmental dysfunction identified through motion palpation. The control group continued routine physical training without manual intervention. All participants underwent pre- and post-assessment of lower-limb strength, power, and endurance. Participants were randomly assigned to the experimental or control group using a computerized random number generator created in Microsoft Excel. The RAND() function was used to generate a random number for each participant, which was then sorted to determine group allocation. An independent researcher—who was not involved in participant recruitment, intervention, or data analysis—managed the sequence and prepared sealed, opaque envelopes to conceal allocation. This process ensured both randomisation integrity and allocation concealment. |
| Intervention type | Other |
| Primary outcome measure | Lower-limb strength measured using 40 kg squat repetitions to fatigue and 1RM squat test (kg) at baseline and after 4 weeks (post-intervention) |
| Secondary outcome measures | 1. Agility measured using the two-point agility test (s) at baseline and post-intervention (week 4) 2. Static balance measured using single-leg balance test (s) at baseline and post-intervention (week 4) 3. Perceived exertion and confidence measured using Session RPE and SRQ immediately after each training session |
| Overall study start date | 01/06/2025 |
| Completion date | 10/09/2025 |
Eligibility
| Participant type(s) | Healthy volunteer, Learner/student |
|---|---|
| Age group | Child |
| Lower age limit | 15 Years |
| Upper age limit | 17 Years |
| Sex | Both |
| Target number of participants | 70 |
| Total final enrolment | 66 |
| Key inclusion criteria | 1. Medically cleared for physical activity 2. Participating in a structured physical training program 3. No musculoskeletal injuries within the past 3 months 4. No prior exposure to spinal manipulation 5. Provided signed informed consent (by participant and legal guardian) |
| Key exclusion criteria | 1. Acute or chronic musculoskeletal injuries 2. Neurological or cardiovascular conditions affecting exercise performance 3. Current use of medications affecting neuromuscular function 4. History of spinal surgery 5. Refusal or inability to provide informed consent |
| Date of first enrolment | 02/08/2025 |
| Date of final enrolment | 05/08/2025 |
Locations
Countries of recruitment
- China
Study participating centre
HeZe
274000
China
Sponsor information
University/education
No.48 Information Rd, Haidian District
Beijing
100084
China
| Phone | +86 1062989244 |
|---|---|
| wsc@bsu.edu.cn | |
| Website | http://en.bsu.edu.cn/ |
"ROR" |
https://ror.org/03w0k0x36 |
Funders
Funder type
Other
No information available
Results and Publications
| Intention to publish date | 01/12/2025 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Planned publication in a peer-reviewed journal specializing in sports science, physical therapy, or chiropractic research. We also intend to present the findings at national and international academic conferences in the fields of sports medicine and adolescent athletic development. |
| IPD sharing plan | The datasets generated during the current study will be available upon reasonable request from the lead researcher, Dr. Qian Zhang (qian.zhang@palmer.edu). The data shared will include de-identified individual performance scores and questionnaire results. Data will be available from December 2025 for up to 5 years. Access will be granted to academic researchers for non-commercial use, subject to ethical approval and data-sharing agreement. Data will be anonymised prior to release to ensure participant confidentiality. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | 28/07/2025 | No | Yes | ||
| Protocol file | 28/07/2025 | No | No |
Additional files
Editorial Notes
25/07/2025: Trial's existence confirmed by Sports Science Experiment Ethics Committee of Beijing Sport University.
