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 |
| ClinicalTrials.gov (NCT) | Nil known |
| Clinical Trials Information System (CTIS) | Nil known |
| Protocol serial number | Nil known |
| Sponsor | Beijing Sport University |
| Funder | Investigator initiated and funded |
- Submission date
- 25/07/2025
- Registration date
- 28/07/2025
- Last edited
- 02/09/2025
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- 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?
June 2025 to August 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
| Primary study design | Interventional |
|---|---|
| Study design | Prospective randomized controlled trial with two parallel groups |
| Secondary study design | Randomised parallel trial |
| 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(s) |
Lower-limb strength measured using 40 kg squat repetitions to fatigue and 1RM squat test (kg) at baseline and after 4 weeks (post-intervention) |
| Key secondary outcome measure(s) |
1. Agility measured using the two-point agility test (s) at baseline and post-intervention (week 4) |
| Completion date | 28/08/2025 |
Eligibility
| Participant type(s) | Healthy volunteer, Learner/student |
|---|---|
| Age group | Child |
| Lower age limit | 15 Years |
| Upper age limit | 17 Years |
| Sex | All |
| Target sample size at registration | 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
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request |
| 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 | ||
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
| Protocol file | 28/07/2025 | No | No |
Additional files
- 47728 Study Protocol.pdf
- Protocol file
- 47728 Participant Information Sheet.pdf
- Participant information sheet
Editorial Notes
02/09/2025: The completion date was changed from 10/09/2025 to 28/08/2025.
25/07/2025: Trial's existence confirmed by Sports Science Experiment Ethics Committee of Beijing Sport University.
