Based on the biomechanical scan of the provided footage, here is the detailed analysis focusing on spinal mechanics, asymmetry, and corrective strategies.
ACTIONABLE STEPS (Priority Order)
- 1Neutralize the Pelvis (Fix Anterior Tilt): You are starting and finishing every rep in excessive lumbar extension (anterior pelvic tilt/swayback). Before descending, you must stack the ribcage over the pelvis.
* *Cue:* "Pull your zipper up to your belly button" or "Exhale and pull your lower ribs down" before you move.
- 2Anti-Rotation Brace (Contralateral Control): In the first clip (Left leg forward), the dumbbell is pulling your right shoulder down, causing a lateral spinal shift. You must actively fight this rotation.
* *Cue:* "Keep your shoulders perfectly level like a shelf" and "Don't let the dumbbell touch your back leg."
- 3Slow the Eccentric Phase: You are "dropping" into the bottom position (approx. 1-1.5s descent), relying on the stretch reflex to bounce out. Increase the lowering time to engage the glute medius and stabilizers.
* *Cue:* "Count 1-2-3 on the way down, pause for 1 second, drive up."
FORM OVERVIEW & SCORE
Form Quality Score: 7/10
You demonstrate excellent mobility and range of motion, achieving full depth with good knee travel. However, spinal integrity is compromised by a lack of core bracing (anterior tilt) and rotational instability on the left side, which suggests a functional asymmetry common in scoliotic presentations.
- Spinal Integrity: 6/10 (Persistent lumbar hyperextension & lateral shift).
- Movement Symmetry: 6.5/10 (Right leg working set is significantly more stable than Left leg).
- Tempo Control: 7/10 (Eccentric is too fast; utilizing momentum).
- Range of Motion: 9.5/10 (Excellent knee flexion and depth).
DETAILED ANALYSIS
Setup Position
- 00:00 (Left Leg Working): Setup width is good. However, your lumbar spine is already in hyper-extension. The pelvis is dumped forward (anterior tilt), disengaging the anterior core.
- 00:26 (Right Leg Working): Similar setup, but the spinal arch is even more pronounced here. The cervical spine (neck) is neutral, which is good, but the "rib flare" is visible.
Eccentric Phase (The Descent)
- 00:02 - 00:04 (Left Leg): The descent is rapid (<2 seconds). As you descend, the right hip (non-working side) drops lower than the left, and the right shoulder dips. The contralateral load (DB in right hand) is winning; your obliques are failing to stabilize the spine against the weight.
- 00:28 - 00:30 (Right Leg): The descent here is cleaner. The pelvis stays more level. The deviation on this side is less about lateral shifting and more about the lumbar arch.
Transition/Bottom Position
- 00:04 (Left Leg): Critical Point. You achieve great depth, but the "stack" is broken. Your torso is leaning right (towards the weight), compressing the right side of the lumbar spine.
- 00:30 (Right Leg): Critical Point. Knee travels well over the toe (healthy dorsiflexion). The back knee hovers perfectly. This side looks structurally stronger, but the lower back is visibly arched, placing shear stress on the L4/L5 vertebrae.
Concentric Phase (The Drive)
- 00:05 & 00:31: Power output is good. You drive effectively through the mid-foot/heel.
- Observation: On the Left Leg set, as you drive up, there is a slight "corkscrew" motion where you have to realign the spine at the top. On the Right Leg set, the path is more vertical and linear.
Lockout/Top Position
- 00:01 & 00:46: At the top, you do not fully extend the hips (squeeze the glutes) to neutral. Instead, you stop with the hips slightly flexed but the lower back arched.
- Correction: Finish the rep by squeezing the glute of the working leg until the hip is flat, rather than leaning back with your torso.
Scoliosis Considerations
- Asymmetry Detected: There is a clear discrepancy between the two sides.
* *Left Leg Forward:* Difficulty maintaining lateral stability. The spine collapses slightly to the right (concave loading issue).
* *Right Leg Forward:* Better lateral stability, but high reliance on lumbar extension.
- Implication: If you have a functional or structural scoliosis, contralateral loading (weight in opposite hand) is high-risk/high-reward. Currently, the load is slightly too heavy for your stabilizing muscles on the Left Leg side, causing the spinal curvature to exaggerate under load.
Rep-to-Rep Consistency
- 00:50 - 01:04 (Fatigue): As the set progresses (Right leg), the reps become faster and "bouncier." The knee valgus (caving in) remains controlled, which is excellent, but the reliance on momentum increases to bypass the sticking point.
Injury Risk Assessment
- Lumbar Facet Joint Irritation (High): The combination of extension + rotation (especially on the first clip) puts significant pressure on the facet joints of the lower back.
- SI Joint Dysfunction (Moderate): The pelvic drop seen at 00:04 can irritate the SI joint on the non-working side.
Programming Recommendations
- 1Regression: Temporarily switch to a Goblet Hold (one dumbbell held at chest height with two hands). This forces the ribs down and core on, immediately fixing the lumbar extension issue.
- 2Corrective Accessory: Perform Pallof Presses. This will teach your core to resist rotation, which is the missing link in your Left-Leg BSS.
- 3Mobility: Focus on Hip Flexor stretches (couch stretch) for the rear leg. Your tight hip flexors on the rear leg are likely pulling your pelvis into that anterior tilt as you descend.
- 4Technique Adjustment: For contralateral loading, reduce the weight by 15-20%. Focus purely on keeping the shoulders parallel to the floor. If the shoulder drops, the set ends.