# NEXT11 / Next Athlete OS — V425 Dynamic Warmup App V2 · Exercises 1–4

## Baseline
- Exact Nex motion baseline: `NEXT11_V425_DYNAMIC_WARMUP_FULL_ROOT.zip`
- Baseline SHA-256: `19a91b1569dda3a0b36094b84ca42f20d4a180e6dc6a53247f3d48ee57e624f2`
- Motion baseline verified before packaging.

## Scope
Presentation/workout-player integration only. No resolved motion JSON, Nex FBX, canonical IK, grip solver, or motion authoring data was changed.

Dynamic Warmup is an 18-exercise standalone user-paced workout through `preview.html?workout=dynamic-warmup#pass`.
Nex loops continuously until the athlete taps the screen to advance. Swipe up opens coaching cues while Nex continues looping.

## Camera and runway correction
- Camera is locked to the Nex front hemisphere in an elevated front-three-quarter product view.
- Target camera height is approximately 0.5 m above Nex's head, angled gently down.
- The runway remains static in world space; Nex presentation root travels through it and the camera tracks Nex.
- Numeric 0/3/6/9 m runway labels remain removed.
- Unlabelled side ticks and short vertical side bars are restored on both runway edges to create visible parallax/travel cues.
- Side markers are world-static and recycle only by an exact marker-spacing multiple.

## Exercise 1 — High Knee Tuck
- Dose: 9 m
- Presentation travel: 0.40 m per alternating tuck step.
- Source-derived contact timing; travel pauses in bilateral-ground and planted-hold windows.

## Exercise 2 — High Knee Run
- Dose: 9 m
- Source cadence: 2.24 s / 6 steps = ~0.3733 s per step.
- Presentation travel: 0.40 m per step.

## Exercise 3 — Hurdle Stretch
- Dose: 9 m
- V425 resolved asset: `hurdle-stretch-v425-contact-corrected.resolved.json`.
- Source two-rep timing window: 5.416667 s.
- Presentation travel: 0.90 m per two-rep loop (~0.45 m per alternating rep), provisional visual calibration.
- Travel pauses during the long planted stretch holds.
- V425 Hurdle profile-identity mismatch is corrected only in resolved-playback integration.

## Exercise 4 — Butt Kick Run
- Dose: 9 m
- V425 resolved asset: `butt-kick-run-v425-contact-corrected.resolved.json`.
- Source timing authority: 10 alternating heel-recovery steps in 4.0 s = 0.400 s per step.
- Presentation travel: 0.40 m per step (~1.0 m/s), provisional visual calibration.
- Source frame review shows continuous running travel with no bilateral-ground plateau within each 0.4 s step, so no artificial root stop is inserted.
- Root speed eases around support/contact transitions rather than moving at a constant treadmill-like velocity.

## QA
- JS syntax checks: PASS.
- JSON parse checks: PASS.
- V425 resolved motion + Nex FBX byte comparison: PASS (65 files checked, 0 changed).
- Clean Hurdle camera/runway QA: `NEXT11_DYNAMIC_WARMUP_V425_EX3_HURDLE_FRONT_CAMERA_SIDE_MARKERS_CLEAN_QA.mp4`.
- Butt Kick Run app QA: `NEXT11_DYNAMIC_WARMUP_V425_APP_EX4_BUTT_KICK_RUN_040M_SOURCE_TIMED_QA_CLEAN.mp4`.