Strength Endurance: Posterior Powerline Test (Bunkie)

Posterior-chain endurance can be relevant for running, sprinting, jumping, field sports, gym training and lower-limb performance.

The Posterior Powerline Test provides a practical way to assess how well a client can maintain a posterior-line hold under load. The test is usually performed bilaterally, with each side tested separately.

The score is the hold time in seconds before form failure, compensation, unacceptable symptoms or voluntary stop. The result should be interpreted alongside hamstring bridge testing, hip thrust strength, leg curl strength, calf endurance, lower-limb symptoms, Bunkie line comparison and movement quality.

Quick Summary

Test name: Posterior Powerline Test
Also known as: Posterior Powerline Bunkie Test
Category: Bunkie endurance / posterior-chain line control
Primary score: Hold time in seconds
Best use: Posterior-chain endurance, side-to-side comparison and baseline/retest tracking
Key limitation: It is not an isolated hamstring test and can be influenced by pelvis, trunk, calf and foot control

What Is This Assessment?

The Posterior Powerline Test is a Bunkie endurance hold performed in a posterior bridge-style position.

The client supports the body using one foot on a bench, box or step while maintaining a straight body line. The opposite leg is positioned according to the selected protocol. The client holds the position while maintaining pelvis height, hip extension and body alignment.

The exact setup must be recorded because bench height, foot position, knee angle, hip position and body alignment all influence the result.

Why It Is Used

The test may be used to assess posterior-chain endurance and side-to-side control.

It may help document:

Posterior-chain endurance
Hamstring and glute contribution
Calf and foot control contribution
Side-to-side differences
Baseline and retest change
Symptom response during posterior loading
Fatigue tolerance during bridge-style tasks
Line-to-line comparison within the Bunkie battery

What It Measures

The primary score is hold time in seconds.

The result may reflect:

Posterior-chain endurance
Hip-extension hold capacity
Hamstring and glute contribution
Calf and foot position control
Pelvis and trunk control
Side-to-side endurance difference
Pain or cramping response
Familiarisation and motivation

It should not be described as isolated hamstring strength or isolated glute endurance.

Who It Is Useful For

The test may be useful for runners, field sport athletes, sprint athletes, gym clients, lower-limb strength clients and professionals monitoring posterior-chain endurance.

It may not be suitable if the client has acute hamstring, calf, back, hip, knee or foot irritability; cramping; poor bridge tolerance; high pain; or inability to maintain a safe supported position.

Equipment Required

Bunkie bench, box or step of standard height
Mat
Stopwatch or Measurz stopwatch
Optional Measurz AR measurement for bench height and setup
Optional inclinometer for pelvis or body alignment
Measurz platform for side, position, time, symptoms, compensations and comparison

Step-by-Step Protocol

1. Set the bench, box or step to a standardised height.
2. Position the client supine in the posterior powerline setup.
3. Place the tested foot on the bench according to the selected protocol.
4. Record the side tested first.
5. Ask the client to lift into the bridge position and maintain a straight line through the trunk, pelvis and supported leg.
6. Start timing once the correct position is achieved.
7. Stop when the pelvis drops, the client loses alignment, cramping occurs, symptoms become unacceptable or the client chooses to stop.
8. Record hold time, side tested and reason for stopping.
9. Repeat on the opposite side after consistent rest.

Scoring and Interpretation

Record hold time in seconds for each side.

Interpretation should include:

Side tested
Hold time
Bench height
Foot position
Pelvis position
Knee angle
Pain or cramping
Compensation
Reason for stopping
Comparison side
Previous baseline

A longer hold time generally suggests better posterior-line endurance under the selected Bunkie setup. Interpretation should still consider cramping, fatigue, symptoms, pelvis control, foot pressure and familiarity.

The most useful comparisons are side-to-side difference, baseline versus retest and posterior powerline performance compared with other Bunkie lines.

Normative Data, Benchmarks or Reference Values

Bunkie Test research has reported descriptive data in healthy adults. Field protocols often use 20–40 seconds as a practical range.

A simple field guide is:

40+ seconds: strong current tolerance
20–39 seconds: moderate current tolerance
10–19 seconds: developing current tolerance
Under 10 seconds: low current tolerance

Use these as context only. Baseline, retesting and side-to-side comparison are more important than rigid cut-offs.

Reliability and Validity

Reliability depends on consistent bench height, foot position, knee angle, pelvis position, side order, rest period, instructions and stopping criteria.

The Posterior Powerline Test may provide useful field information about posterior-chain endurance and line-based stability, but it should not be used alone to diagnose hamstring injury risk, back pain, return-to-sport readiness or posterior-chain function.

Common Errors and Limitations

Common errors include changing bench height, changing foot position, allowing pelvis drop, overusing the lower back, losing hip extension, cramping without recording it, testing while fatigued, not recording side and comparing different protocol versions.

Limitations include cramping, setup variability, fatigue, learning effect, motivation and contribution from multiple body regions.

Practical Applications

Use this test to monitor posterior-chain endurance, compare sides and track response to training.

It is most useful when interpreted alongside hamstring bridge endurance, hip thrust testing, leg curl testing, calf endurance, sprint exposure, lower-limb symptoms and movement quality.

How to Record This in Measurz / MAT

Record:

Test name
Bunkie line
Side tested
Hold time
Bench height
Foot position
Knee angle
Pelvis position
Pain score
Cramping
Symptom location
Compensation
Reason for stopping
Retest date

Use the Measurz stopwatch for timing. AR measurement can help document bench height and setup. Inclinometer notes may help document pelvis or body-line position if needed.

FAQs

What does the Posterior Powerline Test measure?

It measures posterior-line endurance during a Bunkie bridge-style hold.

Is it a hamstring test?

It may involve the hamstrings, but it is not an isolated hamstring test. It also involves glute, calf, trunk and pelvis control.

Should both sides be tested?

Yes. Side-to-side comparison is one of the most useful parts of the test.

What is a good score?

Many field protocols use 20–40 seconds as a practical guide, but baseline and retest comparison are more useful.

Should cramping be recorded?

Yes. Cramping, pain, fatigue and reason for stopping should all be recorded.

Key Takeaways

The Posterior Powerline Test is a Bunkie posterior-chain endurance hold.
The primary score is hold time in seconds.
Side-to-side comparison is highly useful.
Cramping and pelvis drop should be recorded.
The result should not be treated as isolated hamstring or glute function.
Measurz should capture time, side, setup, symptoms and compensation.

References

Brumitt, J., Matheson, J. W., Meira, E. P., et al. (2015). The Bunkie test: Descriptive data for a novel test of core muscular endurance. Rehabilitation Research and Practice, 2015, Article ID 780127.

Cronin, J., et al. (2019). Assessment and application of the Bunkie test in college students. Journal of Bodywork and Movement Therapies.

de Witt, B., & Venter, R. (2009). The Bunkie test: Assessing functional strength to restore function through fascia manipulation. Journal of Bodywork and Movement Therapies.