Based on the biomechanical protocol, here is the detailed analysis of the Bulgarian Split Squat (Rear Foot Elevated Split Squat) performance.
ACTIONABLE STEPS (Priority Order)
- 1LOWER THE REAR FOOT ELEVATION (Critical Correction)
* The Issue: Your rear foot is placed on the second tier of a dumbbell rack, which is significantly too high (approx. hip height). This places the rear hip flexor (rectus femoris/psoas) into extreme passive tension, forcing your pelvis into Anterior Pelvic Tilt (APT) and blocking your ability to descend.
* The Cue: "Use a bench or a box that is knee-height or lower." Ideally, the rear foot should be roughly 12-16 inches off the ground, not 30+.
- 2INCREASE RANGE OF MOTION (ROM)
* The Issue: You are currently performing partial reps (approx. 45-50 degrees of knee flexion) because the rear hip tightness is acting as a mechanical brake. You are missing the most hypertrophic portion of the lift (the bottom stretch).
* The Cue: "Drop the weight significantly. Aim to lightly tap the back knee to the floor (or a pad) while maintaining a neutral spine."
- 3ADJUST TORSO ANGLE TO "STACK" THE SPINE
* The Issue: To compensate for the rear leg pulling your pelvis forward, you are hyperextending your lumbar spine (arching hard) to keep your chest up.
* The Cue: "Hinge forward slightly at the hips (approx. 15-20 degrees). Keep ribs knitted down to your pelvis. Make your torso and rear thigh form a straight diagonal line."
FORM OVERVIEW & SCORE
Form Quality Score: 4/10
The load (28kg dumbbells) is impressive, but it is masking significant mechanical inefficiencies. The setup (rear foot height) is biomechanically disadvantageous, forcing lumbar hyperextension and preventing effective range of motion. The movement is currently straining the lower back more than it is stimulating the quads or glutes.
- Spinal Integrity: 3/10 (Significant lumbar hyperextension under heavy load).
- Movement Symmetry: 6/10 (Hard to judge L/R balance, but sagittal stability is shaky).
- Tempo Control: 7/10 (Controlled eccentric, though limited by ROM).
- Range of Motion: 2/10 (Partial reps; missing the lengthened muscle position).
DETAILED ANALYSIS
Setup Position (00:00 - 00:03)
- Observation: The rear foot is placed on a dumbbell rack shelf that appears to be above knee height.
- Biomechanics: This creates an extreme hip extension demand on the trailing leg before the rep even begins. To stand upright, the pelvis dumps forward (anterior tilt), compressing the lumbar facet joints.
- Correction: Use a standard bench or a specialized single-leg squat roller.
Eccentric Phase (Descent)
- Timestamps: 00:04, 00:12, 00:20
- Analysis: Descent is initiated, but stops abruptly. The front knee tracks forward slightly, but the primary limitation is the *rear* hip. The rear rectus femoris runs out of length, acting as a tether that prevents the hips from sinking lower.
- Joint Stacking: The ear is behind the hips, indicating the torso is leaning back relative to the pelvis, further exacerbating the lumbar arch.
Transition/Bottom Position
- Timestamps: 00:05, 00:13, 00:21
- Depth Check: Maximum knee flexion is approximately 50 degrees. Parallel requires ~90+ degrees.
- Mechanical Block: You are hitting a "tissue block" (tightness in the rear leg) rather than a muscular failure point in the working leg. The working glute is barely entering its active range, and the quad is only working in the mid-range.
Concentric Phase (Drive)
- Power Generation: Drive is initiated through the mid-foot/heel. However, because the descent is shallow, the concentric phase relies heavily on the "stretch reflex" of the tight rear hip flexor rather than pure muscular contraction of the front leg.
- Speed: Velocity is consistent, suggesting strength is present, but form is the limiting factor.
Rep-to-Rep Consistency
- The mechanics are identical across reps, suggesting this is a learned motor pattern. The depth does not degrade because it is mechanically limited by the setup from the very first rep.
Scoliosis Considerations
- Risk Factor: High.
- Mechanism: Heavy split squats create a rotational shear force on the pelvis. Combining this with lumbar hyperextension (due to the high foot placement) is a mechanism for facet joint irritation. If a scoliotic curve is present, this setup will likely compress the concave side of the curve significantly.
- Modification: Lowering the rear foot and leaning the torso forward will open up the spinal facet joints and reduce compressive forces on the lumbar curve.
Injury Risk Assessment
- Primary Risk: Lumbar Spine. The "crunched" position of the lower back under heavy load creates high shear forces.
- Secondary Risk: Rear Hip/Groin. Strain risk to the psoas or rectus femoris due to over-stretching under load.
Programming Recommendations
- 1Regression: Switch to a Split Squat (both feet on floor) or Front Foot Elevated Split Squat. This will allow you to master hip separation and full depth without the balance/flexibility demand of the rear foot elevation.
- 2Mobility: Couch stretch and hip flexor distraction work are required to open the hips.
- 3Technique Reset: Drop the weight to 12-14kg. Set up a low box (12 inches). Practice getting the back knee within 1 inch of the floor. Build strength through the *full* range of motion before increasing load again.