Squat Jump Performance and Chiropractic Ankle Manipulation

The Effects of Chiropractic Ankle Manipulation on Athletic Performance of College-Aged Recreational Athletes: Randomized Controlled Trial

The goal of this clinical trial is to learn if chiropractic ankle manipulation can improve squat jump performance. It will also learn about the relationship among chiropractic ankle manipulation, ankle range of motion, and squat jump performance. The main questions it aims to answer are:

• Does chiropractic ankle manipulation increase squat jump height?
• Is there a relationship among chiropractic ankle manipulation, ankle range of motion, and squat jump performance?

Researchers will compare squat jump performance between subjects who receive chiropractic ankle manipulations with control subjects to see if ankle chiropractic manipulation works to improve squat jump performance.

Participants will:

• Visit the research laboratory for one testing session to measure ankle range of motion and squat jump performance, before and after their randomly assigned intervention arm
• Receive either a chiropractic ankle manipulations or rest quietly as the control condition during the testing session.

Study Overview

• Status: Not yet recruiting
• Conditions: Athletic Performance; Lower Limb; Neuromuscular Adaptations; Chiropractic Manipulation
• Intervention / Treatment: Other: Manual Therapy Procedure: Chiropractic Ankle Manipulation

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Jeanmarie R Burke, PhD; Phone Number: 315 568-3869; Email: jburke@northeastcollege.edu

Study Locations

• United States
  • New York
    • Seneca Falls, New York, United States, 13148
      • Biomechanics Laboratory at Northeast College of Health Sciences
      • Contact: Jeanmarie R Burke, PhD; Email: jburke@northeastcollege.edu

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria

• age range from 18 to 35 years old; and
• participating in recreational exercise, three times a week for at least 30 minutes. Recreational exercise includes ball sports (e.g. soccer, basketball, volleyball, etc.), racket sports (e.g. tennis, pickle ball, racket ball, etc.), strength/combat sports (e.g. weight lifting, boxing, martial arts, kickboxing, etc.), endurance sports (running, cycling, rock climbing, etc.), snow/ice sports (downhill or cross-county skiing, snow shoeing, hockey, etc.), interval training (e.g., high-intensity interval training), sprint interval training, repeated sprint training etc.) or moderate-intensity aerobic activities (step classes, dance classes, hiking, etc.)

Exclusion Criteria

• professional or amateur ranked athlete;
• participation in water sports (swimming, water aerobics, kayaking, water skiing, etc.) to meet the recreational exercise inclusion criteria
• acute or chronic musculoskeletal injury / condition of the feet, ankles, knees, and/or hips;
• acute or chronic musculoskeletal injury / condition of the spine;
• pregnancy or there is a possibility of pregnancy.
• any diagnosed medical condition; and
• any prescribed medications with the exceptions of birth control, anxiety, or attention-deficit/hyperactivity disorder (ADHD) medications.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Chiropractic Ankle Manipulation; LEM - Lower Extremity Manipulation: Subjects assigned to the LEM Intervention Group will receive a short lever, high velocity, low-amplitude distractive (caudal) thrust directed at the talocrural joint. The treating chiropractor will deliver the LEM to the right ankle then the left ankle. LEM is an adjustment for long axis distraction of the tibiotalar joint with the goal to improve dorsiflexion of the ankle joint.	Other: Manual Therapy Procedure: Chiropractic Ankle Manipulation; The lower extremity manipulation (LEM) procedure is a short lever, high velocity, low-amplitude distractive (caudal) thrust directed at the talocrural joint. The treating chiropractor will deliver the LEM to the right ankle then the left ankle. LEM is an adjustment for long axis distraction of the tibiotalar joint with the goal to improve dorsiflexion of the ankle joint.; Other Names: Lower Extremity Manipulation
No Intervention: Control; Subjects assigned to the Control Group will rest quietly, supine (face up), on the chiropractic treatment table for five (5) minutes.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Squat Jump Height	Subjects will be instructed to jump upwards from the starting squat position as high as possible. Subjects will perform 3 to 6 jumps with 3 consecutive jump heights being within 5% of each other to ensure maximum jump height is achieved. There will be a one-minute rest between jumps.; Starting position. Subjects will assume the starting squat position with their hips at 90°, knees at 120°, and ankles at 85° as positioned by the PI. An adjustable plyometric jump box will be used to standardize the starting position. Hands will be resting across their chest with the trunk and head positioned straight ahead.; Squat Jump: Subjects will be instructed to jump as high as possible and land in a comfortable position. Hands will remain across the chest for the duration of The Optojump photoelectric cell system (OptoJump) will be used to record jump height. OptoJump demonstrates strong concurrent validity and excellent test-retest reliability for the estimation of vertical jump height	Baseline on Day 1 to Immediately after Intervention on Day 1
Range of Motion of Ankle Dorsiflexion	Knee-to-wall ankle dorsiflexion test: Ankle dorsiflexion ROM (distance from wall - cm) is the maximum distance of the big toe from the wall while maintaining contact between the wall and the knee with the heel on the ground.; The subject will repeat the Knee-to-wall ankle dorsiflexion test three times at this maximum distance to allow the PI to record three goniometer measurements of ankle dorsiflexion ROM (degrees°).	Baseline on Day 1 to Immediately after Treatment on Day 1 and at End of Test Session on Day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Leg Muscle Power (W/Kg)	Squat Jump Muscle Parameter: The Optojump will calculate an estimate of leg muscle power (W/Kg). The reliability and concurrent validity of OptoJump to measure jump height suggests that the evidence-base biomechanical formula to calculate the estimate of leg muscle power by OptoJump is reliable with face validity.	Baseline on Day 1 to Immediately after Intervention on Day 1
Contraction Velocity of Leg Muscles (mm/s), Force-Velocity Curve	Squat Jump Muscle Parameter: The Gyko inertial sensor system (Gyko) will measure the velocity of the jump to calculate an estimate of the contraction velocity of leg muscles, force-velocity curve. The reliability and concurrent validity of Gyko to measure jump height and in-turn estimate muscle function parameters is limited in the literature. The control group in the current study will allow us to address concurrent validity and reliability of Gyko to measure jump height. Jump height measured by Optojump is the gold-standard field base device. Comparison of Gyko to Optojump measurements of jump heights will determine concurrent validity of Gyko to estimate jump height. The use of evidence-base biomechanical formulas to calculate an estimate of contraction velocity of leg muscles during SQJ's depends on recording reliable and valid measurements of jump heights; and in turn, establish the reliability and face validity of Gyko to estimate muscle function parameters.	Baseline on Day 1 to Immediately after Intervention on Day 1
Rate of Force Development of Leg Muscles (N/s), Slope of the Force - Velocity Curve	Squat Jump Muscle Parameter: The Gyko inertial sensor system (Gyko) will measure the velocity of the jump to calculate an estimate of the rate of force development of leg muscles, slope of the force - velocity curve The reliability and concurrent validity of Gyko to measure jump height and in-turn estimate muscle function parameters is limited in the literature. The control group in the current study will allow us to address concurrent validity and reliability of Gyko to measure jump height. Jump height measured by Optojump is the gold-standard field base device. Comparison of Gyko to Optojump measurements of jump heights will determine concurrent validity of Gyko to estimate jump height. The use of evidence-base biomechanical formulas to calculate an estimate of the rate of force development of leg muscles during SQJ's depends on recording reliable and valid measurements of jump heights; and in turn, establish the reliability and face validity of Gyko to estimate muscle function.	Baseline on Day 1 to Immediately after Intervention on Day 1

Collaborators and Investigators

• Sponsor: Northeast College of Health Sciences

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): May 1, 2027
• Study Completion (Estimated): May 1, 2027

Study Registration Dates

• First Submitted: May 31, 2026
• First Submitted That Met QC Criteria: June 7, 2026
• First Posted (Actual): June 11, 2026

Study Record Updates

• Last Update Posted (Actual): June 11, 2026
• Last Update Submitted That Met QC Criteria: June 7, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: ankle; manipulation; chiropractic; athletic performance; squat jump
• Other Study ID Numbers: 26-02

Drug and device information, study documents

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