Biomechanics Validation
When reviewing jump metrics, validate against these norms:
RSI (Reactive Strength Index)
Population RSI Range
Recreational 0.5-1.5
Trained 1.5-2.5
Elite 2.5-3.5
Flag values > 3.5 as potentially erroneous (measurement or technique issue).
CMJ Jump Height
Population Male (cm) Female (cm)
Recreational 25-40 20-35
Trained 40-55 35-45
Elite 55-70+ 45-55+
Ground Contact Time (Drop Jump)
Range Interpretation
< 100 ms Likely sensor/detection error
150-250 ms Optimal reactive strength
250-350 ms Acceptable, technique improvement possible
400 ms Technique issue or fatigue
Flight Time
Jump Type Typical Range Flag If
CMJ 400-600 ms
800 ms
Drop Jump 350-550 ms
700 ms
Triple Extension (CMJ)
All three joints should approach full extension at takeoff:
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Hip: > 160° (optimal: 170-180°)
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Knee: > 160° (optimal: 170-180°)
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Ankle: > 130° (plantar flexion)
Countermovement Depth (CMJ)
Depth Interpretation
< 20 cm Shallow - may limit power generation
20-40 cm Optimal range
50 cm Deep - may indicate technique issue
Validation Response Format
When validating metrics, provide:
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Status: Normal / Warning / Error
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Value: The actual metric value
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Expected Range: Population-appropriate range
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Interpretation: Coaching-friendly explanation
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Recommendation: If outside norms, suggest next steps
Example Validation
RSI: 2.8 Status: Normal (Elite range) Expected: 2.5-3.5 for elite athletes Interpretation: Excellent reactive strength capability
Ground Contact Time: 85 ms Status: Warning Expected: 150-250 ms optimal Interpretation: Unusually short - likely detection error Recommendation: Review debug video for takeoff/landing detection accuracy