The Neck Extension Strength Test measures how much force a client can produce when pushing the head and neck backward against resistance. It is commonly used to assess cervical extensor force output in a controlled isometric setup.

Neck extension strength can provide useful context for head and neck strength profiling, posture tolerance, contact sport, helmeted sport, occupational demands, progress tracking and comparison with other cervical strength directions. The main contributors include the cervical extensors and upper posterior neck muscles, although trunk position, shoulder position, jaw position, head angle and client confidence can all influence the result.

The Muscle Meter is a handheld dynamometry tool used to measure force output during push, pull and isometric strength assessments. When used on its own, the Muscle Meter primarily measures peak force, which is the highest force value produced during the test. When used with Measurz, Muscle Meter data can be recorded and analysed with a broader set of strength and force-time metrics, including peak force, impulse, torque, rate of torque development, rate of force development, time to peak and fatigue index.

For routine neck extension testing, peak force is usually the main metric. Force as a percentage of body weight may be useful if directly calculated from the client’s test force and body weight, but cervical strength is usually more meaningful when compared with the client’s own baseline, direction-to-direction profile and a matched protocol. Rate of force development and time to peak may be useful when rapid neck force production matters, such as contact sport or high-speed sport contexts. Impulse may be useful if sustained force over a defined time window is intentionally tested. Fatigue index is only relevant if repeated or sustained neck extension efforts are part of the protocol.

The result can support assessment reasoning and progress tracking, but it does not diagnose neck pain, cervical pathology, nerve involvement, headache source, whiplash status, concussion risk or readiness for sport or work on its own.

What Is the Neck Extension Strength Test?

The Neck Extension Strength Test is an isometric cervical strength assessment where the client attempts to push the head and neck backward into the Muscle Meter, strap or fixed setup without visible movement. The device is usually placed against the back of the head or a head strap positioned to capture backward extension force.

The movement direction is cervical extension. The purpose of the test is to measure how much backward head and neck force the client can produce in a specific position.

Consistent setup matters because body position, head position, neck angle, device placement, strap position, trunk stabilisation, jaw position, client effort and symptom response can all affect the result. This test measures force output in a specific setup. It does not fully measure neck endurance, motor control, pain source, cervical joint status, sport contact tolerance, concussion risk or work readiness on its own.

Step-by-Step Protocol / Practice

1. Prepare the client

Explain that the test measures how strongly they can push the head and neck backward into the Muscle Meter. Record baseline neck symptoms, headache, dizziness, visual symptoms, jaw discomfort, shoulder symptoms, arm symptoms, paraesthesia, fatigue, recent contact exposure, recent training load and confidence with maximal effort.

Use at least one submaximal practice trial so the client understands the direction of force and how to build force smoothly without jaw clenching, breath holding, shoulder shrugging or trunk compensation.

2. Set the client position

Neck extension can be tested prone, seated or standing depending on the protocol and available setup. Prone testing can reduce balance demands and allow better trunk control. Seated or standing testing may be more practical but requires careful trunk stabilisation.

Record:

• Prone, seated, standing or other position
• Head and neck start position
• Cervical angle
• Trunk position
• Shoulder position
• Jaw position if relevant
• Device contact point
• Strap or head harness position if used
• Whether the trunk was stabilised
• Whether symptoms were present before testing

For prone testing, the head and neck should start in a neutral position unless another position is intentionally chosen. For seated or standing testing, keep the trunk upright and stable.

3. Set up the device or straps

For a handheld setup, the professional holds the Muscle Meter against the back of the head while the client pushes backward into it. For stronger clients or improved repeatability, a strap-stabilised or fixed setup may be used.

If using a strap or head harness, record:

• Strap or harness position
• Anchor point
• Strap angle
• Strap length
• Device position
• Whether any pre-tension was used
• Whether the anchor or strap moved during testing

Handheld, strap-stabilised, head harness and fixed-frame scores should be recorded separately unless the protocol supports direct comparison.

4. Place the device, strap or handle

Place the Muscle Meter against the back of the head or into the head strap/harness contact point, depending on the chosen protocol. Avoid uncomfortable pressure on sensitive areas and ensure the contact point is repeatable.

The force direction should be cervical extension. The client should push the head and neck backward into the device without shrugging, extending the trunk or clenching the jaw excessively.

5. Stabilise the position

Stabilise the trunk and shoulders so the client does not compensate with thoracic extension, shoulder retraction, shoulder shrugging, jaw clenching or whole-body effort.

The aim is controlled cervical extension force in the chosen position.

6. Give clear instructions

Use consistent instructions such as:

“Push the back of your head into the device as hard as you can and hold.”
“Build up smoothly, then push hard.”
“Keep your shoulders and body still.”
“Keep your jaw relaxed where possible.”
“Keep breathing.”
“Tell me if you feel neck pain, headache, dizziness, tingling, visual symptoms or anything unusual.”

Use the same wording at retest where possible.

7. Record trials

Use 1–2 practice trials, then record 2–3 maximal trials. A common contraction duration is 3 seconds, although 3–5 seconds may be used if it is recorded and repeated consistently. Rest for 30–60 seconds between trials, or longer if symptoms, dizziness, headache, fatigue or apprehension occur.

Record whether the final score uses the best trial or the average of recorded trials. Either approach may be used if it is applied consistently.

8. Identify invalid trials

Repeat or mark a trial as invalid if:

• The trunk extends or moves
• The shoulders shrug or retract strongly
• The head position changes before the effort
• The jaw clenches strongly or changes the setup
• The device slips
• The strap or anchor moves
• The client pushes with the body instead of the neck
• Pain, headache, dizziness or neurological symptoms limit effort
• The client starts before the device is ready
• The client holds their breath excessively
• The professional cannot hold the device steady

9. Record symptoms

Record neck pain, headache, dizziness, visual symptoms, jaw symptoms, shoulder symptoms, arm symptoms, paraesthesia, confidence, apprehension and symptom response after testing. Do not repeatedly test through worsening symptoms, significant dizziness, neurological symptoms or high pain.

For retesting, match the same body position, head position, device placement, strap setup, instructions, contraction duration, rest period, scoring method and symptom recording.

Why It Is Used

The Neck Extension Strength Test is used to quantify cervical extensor force output in a repeatable setup. It may be useful for:

• Baseline neck strength assessment
• Monitoring change over time
• Comparing neck extension with flexion and lateral flexion
• Supporting contact sport and collision sport strength profiling
• Supporting helmeted sport or occupational head-load assessment reasoning
• Tracking symptom response to resisted cervical extension
• General neck strength profiling
• Client education
• Fitness and performance progress tracking

The test should support assessment reasoning. It should not be used as a stand-alone diagnostic, concussion-risk or clearance measure.

What It Measures

The test primarily measures isometric cervical extension force output in the chosen setup. It reflects the client’s ability to produce backward head and neck force while controlling trunk and shoulder position.

It may provide useful information about:

• Cervical extension force capacity
• Direction-to-direction comparison
• Force relative to body weight, if calculated
• Confidence producing neck force
• Symptom response during resisted neck extension
• Change in force over time
• Relationship between neck strength and related tasks

It does not directly measure:

• Cause of neck pain
• Headache source
• Cervical joint status
• Nerve function
• Concussion risk
• Whiplash status
• Neck endurance
• Sport contact readiness
• Work readiness

Understanding the Result, Reference Values and What to Look For

What a higher or lower result may suggest

A higher score may suggest greater cervical extension force output in that specific setup. A lower score may suggest reduced neck extension force output, but the reason should be interpreted carefully.

Lower force may be influenced by pain, apprehension, poor familiarisation, fatigue, guarding, inconsistent device placement, poor trunk stabilisation, jaw clenching, headache, dizziness, reduced confidence or fear of symptoms.

One result should not be interpreted in isolation. Interpretation is strongest when the same setup is repeated over time and reviewed alongside symptoms, confidence, neck range of motion, neck flexion strength, lateral flexion strength, endurance, sport demands, work demands and functional goals.

What can influence the result

Important influences include:

• Neck pain
• Headache
• Dizziness or vestibular symptoms
• Apprehension
• Poor familiarisation
• Fatigue
• Guarding
• Head and neck angle
• Trunk stabilisation
• Shoulder position
• Shoulder shrugging
• Jaw clenching
• Device placement
• Strap angle
• Breath holding
• Client confidence
• Professional strength if using handheld resistance

Normative, reference and comparative values

Published Muscle Meter-specific universal norms for neck extension are limited. Reference values should therefore be used as context only and not as direct targets unless the protocol is closely matched.

More user-friendly comparison data include:

• In healthy young adults tested with fixed-frame dynamometry, neck strength showed a broad range across directions: approximately 38–383 N in men and 15–223 N in women. These broad ranges show how much sex, body size, neck size and protocol can influence results.
• A study of healthy women using a specialised cervical strength setup reported average maximal isometric neck extension strength around 190.8 ± 31.3 N. In practical terms, 190.8 N is roughly similar to 19.5 kg of force.
• In the same female cervical strength research, extension force was much higher than flexion force. A practical way to interpret this is that extension is often expected to be stronger than flexion in comparable protocols, so direction-to-direction comparison can be useful.
• A handheld dynamometry study in healthy women used a Lafayette device attached to a non-elastic belt with trunk stabilisation and found moderate-to-excellent reliability for cervical strength testing, with reported reliability around ICC 0.79–0.90 for intra-rater and ICC 0.78–0.86 for inter-rater testing.
• In that handheld dynamometry protocol, each maximal contraction was sustained for 3 seconds, repeated 3 times, with 1 minute rest between repetitions and 3 minutes rest between movement directions.
• For repeated testing, the client’s own baseline, repeatability and symptom response are usually more useful than broad population values.
• If force is recorded as a percentage of body weight in Measurz, use it mainly for internal comparison over time. Bodyweight percentage should not be treated as a universal neck extension target unless the comparison data use the same calculation and protocol.

These values and comparisons are best used as context. They can help structure interpretation, but they should not be used as diagnostic, concussion-risk, clearance or pass/fail cut-offs.

Practical interpretation priorities

Use this order:

1. Compare with the client’s own baseline.
2. Compare neck extension with flexion and lateral flexion where relevant.
3. Review force relative to body weight where calculated.
4. Consider symptoms during and after testing.
5. Consider confidence and effort quality.
6. Review whether compensations were present.
7. Compare with neck range of motion and endurance where relevant.
8. Relate the result to sport, work, posture or daily-life demands.
9. Retest under the same conditions to monitor change.
10. Do not use reference values as pass/fail criteria.

What to look at for each relevant Muscle Meter metric

Peak force
Use for maximum neck extension force output, baseline strength, direction-to-direction comparison and progress tracking. Look for best score or average score, consistent setup, change from baseline, symptom response and whether compensations occurred.

Force as percentage of body weight
Use only when calculated directly from test force and body weight. It may help internal monitoring, but it should not be treated as a universal target unless the comparison data use the same protocol.

Torque
Use only when a lever arm is measured and a more biomechanical interpretation is needed. It should not be used as normative data unless the reference data match the setup closely.

Rate of force development
Use when rapid neck force production matters, such as contact sport or high-speed sport contexts. Look for early force production and whether rate of force development changes while peak force stays similar.

Time to peak
Use to understand whether force is produced quickly or gradually. A slower time to peak may reflect caution, symptom concern, poor cueing or a true force-production difference.

Impulse
Use only if a defined sustained force window is intentionally tested. It may help when the aim is to understand force maintained over a brief contraction.

Fatigue index
Use only if repeated or sustained neck extension efforts are part of the protocol. Look for drop-off across repeated trials and whether the decline matches symptoms, fatigue or apprehension.

Assessing and Providing Context for Different Client Populations

Youth clients
Consider growth, maturity, confidence, attention, sport exposure and careful symptom screening. Use conservative familiarisation and avoid forcing maximal efforts if symptoms occur.

Adults and general fitness clients
Use the test for baseline neck strength, progress tracking and comparison with other neck directions. Compare results with posture tolerance, range of motion, endurance and symptoms.

Older adults
Consider comfort, dizziness, headache, balance, neck mobility, fatigue and confidence. Use gentler familiarisation and avoid repeated maximal efforts if symptoms are provoked.

Athletes and sport clients
Consider contact, collision, grappling, heading, motorsport, combat sport and high-speed sport demands. Neck strength can support profiling, but it should not be used alone to judge concussion risk or sport readiness.

Workplace and manual task clients
Consider helmets, head-mounted equipment, driving, machinery operation, prolonged postures, overhead work and repeated head movement. Do not use one score to clear work duties.

Clients returning after injury
Use the test to monitor force output, confidence and symptom response. Strength alone should not confirm readiness.

Clients with pain or persistent symptoms
Pain, headache, dizziness, fear, guarding, fatigue, apprehension and confidence may reduce force. Record symptom response carefully and compare with related tests.

Higher body mass clients
Absolute force and force relative to body mass may both be useful. Interpret results in relation to goals, symptoms, neck size and functional demands, not assumptions about body size.

Reliability, Validity and Measurement Considerations

Repeatability improves when the same setup is used each time. Record and standardise:

• Same body position
• Same head and neck position
• Same cervical angle
• Same trunk stabilisation
• Same shoulder position
• Same jaw instruction
• Same device placement
• Same strap or harness setup, if used
• Same anchor height and distance, if used
• Same contraction duration
• Same rest period
• Same instructions
• Same scoring method
• Same symptom and compensation recording

Neck strength testing is highly setup-dependent. Small changes in head position, device placement, trunk stabilisation or symptom response can change the score. For stronger clients, handheld resistance may be limited by professional strength. Strap-stabilised or fixed setups can improve repeatability.

Common Errors and Limitations

Common errors include:

• Trunk extending or moving
• Shoulder shrugging
• Jaw clenching
• Device placement changing between trials
• Head position changing before the effort
• Breath holding
• Testing through worsening headache or dizziness
• Strap or anchor movement
• Poor familiarisation
• Comparing different protocols directly
• Treating the score as a diagnosis

Limitations include:

• Testing is setup-dependent
• Manual resistance may be limited by professional strength
• Muscle Meter-specific universal norms may be limited
• Published cervical strength values vary by device, posture and population
• Pain, headache, dizziness, fear or guarding can reduce force output
• Peak force does not measure endurance or motor control
• Strong force does not automatically indicate readiness for contact sport or work

Practical Applications

The Neck Extension Strength Test may be useful for:

• Baseline cervical strength assessment
• Monitoring response to exercise or intervention
• Direction-to-direction neck strength profiling
• Contact sport and collision sport strength profiling
• Occupational neck strength profiling
• Comparing with neck flexion, lateral flexion, rotation, range of motion and endurance tests
• Client education
• Fitness and performance progress tracking

Ideas to Make the Result Better

If force is low, consider assessing neck flexion strength, lateral flexion strength, neck range of motion, endurance, posture tolerance, confidence, symptoms and familiarisation.

If extension is much stronger or weaker than expected compared with flexion, interpret this in the context of symptoms, sport or work demands, test setup and baseline data.

If symptoms limit the result, record symptom location and type, review test position and compare with related findings rather than forcing repeated maximal trials.

If force improves but symptoms remain, consider reviewing endurance, range of motion, work/sport exposure, posture tolerance and recovery between sessions.

If the client is improving, keep the same test setup and monitor whether force, symptoms, confidence and function improve together.

Recommended Standard Protocol Summary

Position: Prone, seated, standing or chosen neck extension test position
Start position: Head and neck neutral unless otherwise specified
Joint or trunk angle: Record cervical, trunk and shoulder position
Trials: 1–2 practice trials, then 2–3 recorded trials
Contraction duration: Commonly 3 seconds, or 3–5 seconds if used consistently
Rest: 30–60 seconds between efforts; longer if symptoms occur
Metric: Peak force, plus percentage of body weight if directly calculated
Attachment or device setup: Muscle Meter against posterior head or connected to a head strap/harness with consistent contact point
Final score: Best trial or average of trials
Key retesting requirement: Same body position, head position, device placement, stabilisation, instructions, contraction duration, rest and scoring method

FAQs

What does the Neck Extension Strength Test measure?

It measures isometric cervical extension force output in a specific setup.

Which muscles contribute to neck extension?

The cervical extensor and posterior neck muscles contribute, although trunk position, shoulder position, jaw position and head angle can influence the result.

Should the result be recorded as percentage of body weight?

It can be if calculated directly from force and body weight, but neck extension is usually best interpreted using baseline comparison and a matched retest protocol.

Are there universal neck extension norms for the Muscle Meter?

Published universal Muscle Meter norms for this exact protocol appear limited. Broad cervical strength values exist, but they vary by device, position, sex, body size and protocol.

What numerical values are available for comparison?

Published cervical extension examples include healthy female average values around 190.8 ± 31.3 N, which is roughly 19.5 kg of force. This is useful context but not a direct Muscle Meter target unless the setup is closely matched.

Is neck extension usually stronger than neck flexion?

In many protocols, extension values are higher than flexion values. Compare directions using the same setup and avoid relying on one value alone.

Can this test diagnose neck pain or concussion risk?

No. It can measure force output and symptom response, but it does not diagnose a condition or determine concussion risk on its own.

What can make the result unreliable?

Changing head position, trunk movement, shoulder shrugging, jaw clenching, device slipping, pain, headache, dizziness, fatigue and inconsistent instructions can affect results.

What should be recorded in Measurz?

Record position, head and neck angle, device placement, peak force, symptoms, confidence, compensations, bodyweight-relative value if calculated, scoring method and related findings.

Key Takeaways

• The Neck Extension Strength Test measures isometric cervical extension force output.
• Peak force is usually the main routine Muscle Meter metric.
• Published cervical extension examples include approximately 190.8 ± 31.3 N in healthy women using a specialised setup.
• Neck extension is often stronger than neck flexion in matched protocols, so direction-to-direction comparison is useful.
• Percentage of body weight should only be used when calculated directly from force and body weight.
• Baseline comparison, symptom response and retesting consistency are more useful than broad norms.
• Measurz should capture setup, symptoms, force, confidence, compensations and retesting conditions.

References

Abichandani, D., Tong Yuk Ting, J., Elgueta Cancino, E., Althobaiti, S., & Falla, D. (2023). Measures of neck muscle strength and their measurement properties in adults with chronic neck pain: A systematic review. Systematic Reviews, 12, 6. https://doi.org/10.1186/s13643-022-02162-5

Catenaccio, E., Mu, W., Kaplan, A., Fleysher, R., Kim, N., Bachrach, T., Sears, M. Z., Jaspan, O., Caccese, J., Kim, M., Wagshul, M., Stewart, W. F., Lipton, R. B., & Lipton, M. L. (2017). Characterization of neck strength in healthy young adults. PM&R.

Gorla, C., Martins, T. de S., Florencio, L. L., Pinheiro-Araújo, C. F., Fernández-de-las-Peñas, C., Martins, J., & Bevilaqua-Grossi, D. (2023). Reference values for cervical muscle strength in healthy women using a hand-held dynamometer and the association with age and anthropometric variables. Healthcare, 11(16), 2278. https://doi.org/10.3390/healthcare11162278

Salo, P. K., Ylinen, J. J., Mälkiä, E. A., Kautiainen, H., & Häkkinen, A. H. (2006). Isometric strength of the cervical flexor, extensor, and rotator muscles in 220 healthy females aged 20 to 59 years. Journal of Orthopaedic & Sports Physical Therapy, 36(7), 495–502. https://doi.org/10.2519/jospt.2006.2122

Versteegh, T. H., Beaudet, D. A., Greenbaum, M., Hellyer, L., Tritton, A., & Walton, D. M. (2015). Evaluating the reliability of a novel neck-strength assessment protocol for healthy adults using self-generated resistance with a hand-held dynamometer. Physiotherapy Canada, 67(1), 58–64. https://doi.org/10.3138/ptc.2013-66