# PWR-013 — Reactive strength: learner worksheet Release: Revision 7T · Full Tutorial Edition Estimated time: Estimated 11 min reading; practical time is provider-set Difficulty: Intermediate Equipment: Specialist equipment — Force plate or validated contact-time and jump-height system; Flat resilient non-slip surface with foot marks; Video view of trunk, knees and feet; Stable support outside the landing zone; A rebound sheet showing task, surface, footwear, contact number, ground-contact time, jump height, alignment flag, stopping reason and invalid contacts. Space: Room-scale practice space Automated structural checklist: 10 of 10 structural checks present Evidence quality/context: G4; Focused research depth Automated method-quality band: Comprehensive Method-rating basis: Structure coverage, instruction/check specificity, alternative distinctness, source troubleshooting, comparison depth and whether purpose/check fields are authored rather than derived. Editorial review: Pending manual editorial sign off ## Before you begin - [ ] I read the tutorial authority and stop conditions. - [ ] I have the required equipment/space or a declared accessible alternative. ## Canonical source context Reactive strength is the ability to switch rapidly from landing force to take-off force in a declared rebound. This lesson teaches a provider-controlled low-amplitude bilateral pogo hop on a force plate: establish a stable landing first, keep the trunk tall, contact through the forefoot and whole foot, rebound without a deep squat and stop when contact time, height or alignment deteriorates. The provider controls clearance, hop height, repetitions, rest and whether drop jumps are ever appropriate. Target outcome: The learner completes one short provider-set series of bilateral rebounds with consistent contact time, jump height and alignment, then stops on the first control failure. ### Authority and setup conditions - Demonstrate a quiet two-foot landing and hold balance for two seconds before repeated rebound work. - Report recent tendon, bone, knee, ankle or back symptoms and any long break from jumping. - Agree on contact count and the exact stop rule for height loss, longer contact or alignment error. - Mark the take-off and landing area and rehearse one quiet, low landing. Start the rebound series only when the learner can stay on the marks without stepping, collapsing or reaching for support. - Rehearse the tall ready posture, a quiet landing and one small rebound before starting the provider-limited contact series. ### Required or supplied materials - Force plate or validated contact-time and jump-height system - Flat resilient non-slip surface with foot marks - Video view of trunk, knees and feet - Stable support outside the landing zone - A rebound sheet showing task, surface, footwear, contact number, ground-contact time, jump height, alignment flag, stopping reason and invalid contacts. ## 1. Earn the landing first Complete a provider-set low jump, land on both marked feet and hold for two seconds with hips and knees flexed. Why: Repeated rebound is inappropriate when one landing is not controlled. Success check: The learner stays on the marks without a step or collapse. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “The learner stays on the marks without a step or collapse.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 2. Set the rebound posture Stand tall with feet on the marks, ankles ready and arms in the declared position. Keep the gaze forward. Why: A repeatable start controls arm and trunk contributions. Success check: Feet, arms and trunk match the setup image. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “Feet, arms and trunk match the setup image.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 3. Use a small first hop Rise only to the provider-set low height and return to the same marks; do not chase maximum height. Why: The first contact should establish rhythm, not create an overload. Success check: The first landing is quiet, centred and within the target height range. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “The first landing is quiet, centred and within the target height range.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 4. Rebound from the ankle-led contact On landing, allow the whole foot to load while ankles, knees and hips flex slightly, then push away promptly without a deep squat. Why: A deep, slow countermovement changes the task from short-contact reactive work. Success check: Contact remains brief and the trunk does not fold. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “Contact remains brief and the trunk does not fold.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 5. Keep contacts aligned Track knees in line with feet and keep each contact on the marks. Do not let one leg take over or the feet drift. Why: Drift and collapse show loss of a repeatable rebound pattern. Success check: Video shows centred contacts and similar left-right timing. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “Video shows centred contacts and similar left-right timing.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 6. Stop at the first failed rebound End the set when contact becomes clearly longer, height falls outside the band, alignment breaks or symptoms appear; step out and settle rather than forcing one more hop. Why: Technique failure is the endpoint, not exhaustion. Success check: No extra contacts occur after the first stop criterion. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “No extra contacts occur after the first stop criterion.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## 7. Calculate and interpret RSI For valid contacts, divide jump height by ground-contact time using consistent units and report height and contact time alongside the ratio. Why: The same ratio can hide different height-contact strategies. Success check: The record retains all three values and the exact hop condition. Accessible alternative: Ask the qualified provider to adapt positioning, cue modality, pace, interface or rest while preserving this step’s declared check: “The record retains all three values and the exact hop condition.” If an adaptation changes the measured task or configuration, record it as a different configuration rather than an equivalent attempt. Alternative relationship: Conditional equivalence requires target and configuration check Learner notes: ________________________________________________________________________________ Completed: [ ] ## Reflection What changed? ________________________________________________________________________________ What remains difficult? ________________________________________________________________________________ What will I repeat, adapt, ask for help with, or stop? ________________________________________________________________________________ --- Completion of this worksheet demonstrates tutorial participation only. It does not establish capability, qualification, safety clearance, diagnosis, treatment or independent validation.