Trial Outcomes & Findings for How do the Neck Muscles Influence Head Acceleration During Sport-associated Impact Events in High School Athletes? (NCT NCT03883165)
NCT ID: NCT03883165
Last Updated: 2025-06-24
Results Overview
The linear component of head acceleration was measured with a sensor attached to the head, while a device applied force to the head. The data is reported where higher values represent greater acceleration per amount of force delivered (zero represents no acceleration and greater numbers higher acceleration).
Recruitment status
COMPLETED
Study phase
NA
Target enrollment
48 participants
Primary outcome timeframe
4 weeks, 8 weeks, 12 weeks
Results posted on
2025-06-24
Participant Flow
Enrollment indicates participants who consented. Prior to randomization 5 participants were lost (2 withdrew, 2 lost to follow-up and 1 no longer eligible).
Participant milestones
| Measure |
Control Group
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
High-intensity Neck Strengthening Group
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
|---|---|---|
|
Overall Study
STARTED
|
24
|
19
|
|
Overall Study
Follow-Up Visit 1
|
21
|
19
|
|
Overall Study
Follow-Up Visit 2
|
21
|
18
|
|
Overall Study
Follow-Up Visit 3
|
20
|
16
|
|
Overall Study
COMPLETED
|
20
|
16
|
|
Overall Study
NOT COMPLETED
|
4
|
3
|
Reasons for withdrawal
| Measure |
Control Group
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
High-intensity Neck Strengthening Group
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
|---|---|---|
|
Overall Study
Withdrawal by Subject
|
4
|
3
|
Baseline Characteristics
How do the Neck Muscles Influence Head Acceleration During Sport-associated Impact Events in High School Athletes?
Baseline characteristics by cohort
| Measure |
High-intensity Neck Strengthening Group
n=19 Participants
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
Control Group
n=24 Participants
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
Total
n=43 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
15.11 years
STANDARD_DEVIATION 1.10 • n=5 Participants
|
15.75 years
STANDARD_DEVIATION 1.54 • n=7 Participants
|
15.47 years
STANDARD_DEVIATION 1.39 • n=5 Participants
|
|
Sex: Female, Male
Female
|
8 Participants
n=5 Participants
|
8 Participants
n=7 Participants
|
16 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
11 Participants
n=5 Participants
|
16 Participants
n=7 Participants
|
27 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
3 Participants
n=5 Participants
|
2 Participants
n=7 Participants
|
5 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
16 Participants
n=5 Participants
|
22 Participants
n=7 Participants
|
38 Participants
n=5 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
American Indian or Alaska Native
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Asian
|
1 Participants
n=5 Participants
|
1 Participants
n=7 Participants
|
2 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Black or African American
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
White
|
15 Participants
n=5 Participants
|
19 Participants
n=7 Participants
|
34 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
More than one race
|
3 Participants
n=5 Participants
|
2 Participants
n=7 Participants
|
5 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Other
|
0 Participants
n=5 Participants
|
2 Participants
n=7 Participants
|
2 Participants
n=5 Participants
|
|
Race/Ethnicity, Customized
Unknown or Not Reported
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
19 Participants
n=5 Participants
|
24 Participants
n=7 Participants
|
43 Participants
n=5 Participants
|
PRIMARY outcome
Timeframe: 4 weeks, 8 weeks, 12 weeksPopulation: For the high-intensity group 3 subjects withdrew from follow-up visit 1 to Follow-Up Visit 3. For the control group 4 subjects withdrew from the baseline visit to follow-up visit 3.
The linear component of head acceleration was measured with a sensor attached to the head, while a device applied force to the head. The data is reported where higher values represent greater acceleration per amount of force delivered (zero represents no acceleration and greater numbers higher acceleration).
Outcome measures
| Measure |
High-intensity Neck Strengthening Group
n=19 Participants
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
Control Group
n=24 Participants
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
|---|---|---|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Linear Motion.
Baseline
|
.895 meters per second per joule
Standard Deviation .378
|
1.069 meters per second per joule
Standard Deviation .501
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 1 (4 weeks)
|
.873 meters per second per joule
Standard Deviation .398
|
.903 meters per second per joule
Standard Deviation .491
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 2 (8 weeks)
|
.893 meters per second per joule
Standard Deviation .44
|
.937 meters per second per joule
Standard Deviation .404
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 3 (12 weeks)
|
.839 meters per second per joule
Standard Deviation .392
|
.793 meters per second per joule
Standard Deviation .386
|
PRIMARY outcome
Timeframe: 4 weeks, 8 weeks, 12 weeksPopulation: For the high-intensity group 3 subjects withdrew from follow-up visit 1 to Follow-Up Visit 3. For the control group 4 subjects withdrew from the baseline visit to follow-up visit 3.
The angular component of head acceleration was measured with a sensor attached to the head, while a device applied force to the head. The data is reported where higher values represent greater acceleration per amount of force delivered (zero represents no acceleration and greater numbers higher acceleration).
Outcome measures
| Measure |
High-intensity Neck Strengthening Group
n=19 Participants
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
Control Group
n=24 Participants
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
|---|---|---|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Angular Motion.
Baseline
|
.057 radians per second per joule
Standard Deviation .040
|
.069 radians per second per joule
Standard Deviation .047
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 1 (4 weeks)
|
.054 radians per second per joule
Standard Deviation .036
|
.058 radians per second per joule
Standard Deviation .043
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 2 (8 weeks)
|
.056 radians per second per joule
Standard Deviation .037
|
.063 radians per second per joule
Standard Deviation .039
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Direct Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 3 (12 weeks)
|
.05 radians per second per joule
Standard Deviation .039
|
.049 radians per second per joule
Standard Deviation .035
|
SECONDARY outcome
Timeframe: 4 weeks, 8 weeks, 12 weeksPopulation: For the high-intensity group 3 subjects withdrew from follow-up visit 1 to Follow-Up Visit 3. For the control group 4 subjects withdrew from the baseline visit to follow-up visit 3.
The linear component of head acceleration was measured with a sensor attached to the head, while a simulated body check was administered. The data is reported where higher values represent greater acceleration (zero represents no acceleration and greater numbers higher acceleration).
Outcome measures
| Measure |
High-intensity Neck Strengthening Group
n=19 Participants
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
Control Group
n=24 Participants
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
|---|---|---|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Linear Motion.
Baseline
|
1.007 meters per second
Standard Deviation 0.417
|
1.105 meters per second
Standard Deviation 0.432
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 1 (4 weeks)
|
1.007 meters per second
Standard Deviation 0.418
|
0.943 meters per second
Standard Deviation 0.403
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 2 (8 weeks)
|
0.999 meters per second
Standard Deviation 0.367
|
0.973 meters per second
Standard Deviation 0.323
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Linear Motion.
Follow-Up Visit 3 (12 weeks)
|
0.938 meters per second
Standard Deviation 0.367
|
1.007 meters per second
Standard Deviation 0.397
|
SECONDARY outcome
Timeframe: 4 weeks, 8 weeks, 12 weeksPopulation: For the high-intensity group 3 subjects withdrew from follow-up visit 1 to Follow-Up Visit 3. For the control group 4 subjects withdrew from the baseline visit to follow-up visit 3.
The angular component of head acceleration was measured with a sensor attached to the head, while a simulated body check was administered. The data is reported where higher values represent greater acceleration (zero represents no acceleration and greater numbers higher acceleration).
Outcome measures
| Measure |
High-intensity Neck Strengthening Group
n=19 Participants
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
Control Group
n=24 Participants
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
|---|---|---|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Angular Motion.
Baseline
|
0.020 radians per second
Standard Deviation 0.010
|
0.020 radians per second
Standard Deviation 0.008
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 1 (4 weeks)
|
0.02 radians per second
Standard Deviation 0.011
|
0.018 radians per second
Standard Deviation 0.01
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 2 (8 weeks)
|
0.02 radians per second
Standard Deviation 0.008
|
0.019 radians per second
Standard Deviation 0.008
|
|
Mean Area Under the Net Head Acceleration vs. Time Curve During Indirect Loading, With Anticipatory Bracing - Angular Motion.
Follow-Up Visit 3 (12 weeks)
|
0.019 radians per second
Standard Deviation 0.009
|
0.019 radians per second
Standard Deviation 0.009
|
Adverse Events
Control Group
Serious events: 1 serious events
Other events: 15 other events
Deaths: 0 deaths
High-intensity Neck Strengthening Group
Serious events: 1 serious events
Other events: 11 other events
Deaths: 0 deaths
Serious adverse events
| Measure |
Control Group
n=24 participants at risk
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
High-intensity Neck Strengthening Group
n=19 participants at risk
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
|---|---|---|
|
Gastrointestinal disorders
Nausea
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Gastrointestinal disorders
vomiting
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Gastrointestinal disorders
Diarrhea
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Eye disorders
conjunctivitis
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
Other adverse events
| Measure |
Control Group
n=24 participants at risk
Control group: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting only the chest, shoulders, back, upper and lower extremities, and core, without resistance exercises specifically targeting the neck.
|
High-intensity Neck Strengthening Group
n=19 participants at risk
high-intensity neck strengthening: All subjects will exercise 2 days per week for 12 weeks under the direct supervision of a study-assigned strength coach with a minimum of 1 day of rest between exercise sessions.
Participants will perform a standardized set of general resistance exercises targeting the chest, shoulders, back, upper and lower extremities, and core. Additionally, they will also perform a higher number of repetitions of manual resistance neck strengthening exercises in sagittal plane flexion and extension, coronal plane lateral flexion in both directions, and axial plane rotation in both directions,as well as dumbbell shoulder shrugs.
|
|---|---|---|
|
General disorders
Back pain
|
8.3%
2/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Minor hand injury
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
General disorders
Headache
|
8.3%
2/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Gastrointestinal disorders
Nausea
|
8.3%
2/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Surgical and medical procedures
Wisdom teeth removal surgery
|
8.3%
2/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
General disorders
Sore throat
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Gastrointestinal disorders
Vomiting
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Musculoskeletal and connective tissue disorders
Calf cramping
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Nervous system disorders
Bilateral nerve pain in arms
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Musculoskeletal and connective tissue disorders
Shoulder pain
|
4.2%
1/24 • Up to four months
|
10.5%
2/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Ankle injury
|
4.2%
1/24 • Up to four months
|
15.8%
3/19 • Up to four months
|
|
Infections and infestations
Cold/flu symptoms
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Musculoskeletal and connective tissue disorders
Hip pain
|
4.2%
1/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Infections and infestations
COVID
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Musculoskeletal and connective tissue disorders
Knee discomfort
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
General disorders
Back spasms
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
General disorders
Fatigue after extensive exertion
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
General disorders
Neck pain
|
0.00%
0/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Knee injury
|
4.2%
1/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Toe injury
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Suspected concussion
|
4.2%
1/24 • Up to four months
|
5.3%
1/19 • Up to four months
|
|
Injury, poisoning and procedural complications
Confirmed concussion
|
4.2%
1/24 • Up to four months
|
0.00%
0/19 • Up to four months
|
Additional Information
James T Eckner, MD, MS
University of Michigan Medical School
Phone: 734-647-5568
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place