From Data to Development with Rapsodo

5 Critical Metrics That Transform Your Coaching

1. SPIN DIRECTION: The Bat Path Detective

What It Tells You: Reveals bat path at contact better than video alone

Spin Direction Guide:

IDEAL: 12:00 (Pure Backspin) → Upward bat path, matched pitch plane
PROBLEM: 6:00 (Topspin) → Downward/chopping bat path
PROBLEM: 3:00 (RHH Pull Spin) → Rolling over, early rotation
PROBLEM: 9:00 (RHH Oppo Spin) → Late contact, bat drag

✓ Quick Fix Guide:

Topspin → Check: hand drop, posture collapse, early extension
Pull-side spin → Check: early rotation, weak front side
Oppo spin → Check: passive lower half, late timing

2. SPIN RATE: The Barrel Control Indicator

What It Tells You: Whether contact was centered on sweet spot

Spin Rate Ranges:

HIGH (1800-2500+ RPM): Sweet spot contact, good barrel control
LOW (<1500 RPM): Mishit (toe/handle), timing issues

✓ Key Insight: 70 MPH with 1200 RPM = mishit that felt good | 65 MPH with 2200 RPM = well-struck ball, just needs strength

✓ If spin rate is consistently low → Work on timing, barrel awareness, vision tracking

3. EXIT VELOCITY + LAUNCH ANGLE: The Power-Efficiency Equation

What It Tells You: Whether power and path are working together

OPTIMAL RANGES (Fastpitch):

Exit Velo: 70+ MPH (elite HS/college), 65-70 (good HS), 60-65 (developing)
Launch Angle: 15-30 degrees (line drives/hard fly balls)

RED FLAG #1: High LA + Low EV (Rainbow Ball Hitter)

Example: 32° LA, 58 MPH EV = Lazy fly ball

Problem: Lifting with arms, not rotating with body
Fix: Ground force mechanics, rotational power, connection drills

RED FLAG #2: High EV + Low LA (Ground Ball Machine)

Example: 72 MPH EV, 5° LA = Hard ground ball (wasted power)

Problem: Bat path too steep/flat
Fix: Attack angle drills, posture maintenance, high tee work

4. PULL vs. OPPOSITE FIELD EXIT VELO: Directional Power Profile

What It Tells You: Whether hitter can drive ball to all fields or is one-dimensional

IDEAL: 2-5 MPH drop from pull to oppo

Example: 70 MPH pull, 66-68 oppo = Complete hitter who can use all fields

RED FLAG #1: Massive Pull Dominance (10+ MPH gap)

Example: 72 MPH pull, 58 MPH oppo = 14 MPH gap

Problem: Early rotation, pulling off, can't extend oppo
Fix: Oppo tee work, front side connection, two-strike approach

RED FLAG #2: Weak Pull-Side Power (oppo stronger than pull)

Example: 63 MPH pull, 64 MPH oppo

Problem: Passive rotation, late timing, "pushing" the ball
Fix: Rotational power drills, pull-side BP, "turn and burn"

✓ Game Application: Hitters with 10+ MPH gaps get exploited by pitchers (one-dimensional = predictable)

5. BAT SPEED vs. EXIT VELO: The Efficiency Equation

What It Tells You: Whether hitter is converting effort into results
(Requires Swing Tracker/Blast/Diamond Kinetics + Rapsodo)

EFFICIENCY RATIO = Exit Velocity ÷ Bat Speed

OPTIMAL: 1.0 to 1.1 ratio
Example: 65 MPH bat speed → 68 MPH exit velo = 1.05 (excellent)

THE PROBLEM: Swinging Harder ≠ Hitting Harder

Real Example:

Swing 1: 66 MPH bat speed → 69 MPH EV (1.05 ratio) ✓
Swing 2: 73 MPH bat speed → 66 MPH EV (0.90 ratio) ✗ OVER-SWINGING
Swing 3: 67 MPH bat speed → 70 MPH EV (1.04 ratio) ✓

WHY MAX EFFORT FAILS:

✗ Loss of barrel control (more mishits)
✗ Mechanical breakdown (front shoulder flies, head pulls off)
✗ Tension (muscles lock up)
✗ Poor timing adjustments

✓ The 80-85% Rule: Best hitters swing at 80-85% max effort

Allows barrel control
Maintains mechanics
Produces highest exit velo through efficiency

✓ Quick Drill: "Dial It Down Challenge"

Have hitter take 5 max effort swings (record bat speed + exit velo)
Have hitter take 5 swings at 80% effort ("smooth and controlled")
Show them the controlled swings produce better exit velo
Reinforce: "Your job is to hit the ball hard, not swing hard"

The Complete Game Approach: Data + Vision + Customized Drills

INTEGRATED TECHNOLOGY = COMPLETE PICTURE

Rapsodo (OUTPUT)

Exit velocity
Launch angle
Spin direction
Spin rate

Swing Tracker (INPUT)

Bat speed
Attack angle
Time to contact
Acceleration metrics

= EFFICIENCY

How well are they converting effort into results?

+ VISION TRAINING (Complete Game Methodology)

If metrics are inconsistent despite good mechanics → check vision
Dynamic visual acuity, pitch tracking, depth perception
Data without vision = incomplete; Vision without data = guesswork

Quick Reference: Diagnostic Flowchart

IF YOU SEE...	CHECK FOR...
Low Exit Velo + High LA	Disconnection, poor sequencing, weak ground forces
High Exit Velo + Low LA	Steep bat path, posture collapse
Heavy Topspin	Hand drop, early extension, downward path
Pull-Side Spin	Early rotation, rolling over
Low Spin Rate (any swing)	Timing issues, barrel control, vision tracking
Big Pull/Oppo Gap (10+ MPH)	Early rotation OR passive rotation
Low Efficiency Ratio (<0.95)	Over-swinging, tension, mechanical breakdown

"The data tells us WHAT. Our coaching eye tells us WHY. Customized drills fix it."

— Rob Crews, Complete Game