Butterfly Start Model Example (Limited Mode)

1. Phase Structure

Reaction and block preparation
Take-off impulse generation
Flight trajectory control
Water entry and streamline alignment
Underwater glide
Underwater dolphin kicking (Most important Phase of start)
Double-arm pullout
Breakout transition
First surface stroke stabilization

In butterfly, freestyle, and backstroke starts, the underwater kicking is the most decisive competitive phase. Dominance in underwater velocity and stability determines start success.

2. Quantitative Parameter Structure

Phase	Parameter	Importance
Reaction	Reaction time	High
Take-off	Block impulse duration	High
Flight	Flight distance	Medium
Entry	Entry angle	High
Underwater	Dolphin kick frequency	Primary
Underwater	Kick amplitude control	Primary
Underwater	Velocity stability	Primary
Underwater	Distance to breakout	Primary
Transition	Breakout timing	High
Surface	First stroke synchronization	Supportive

Primary parameters must be stabilized before secondary corrections are applied.

Complete Measured Parameters Example (23 Parameters)

No. & Parameter	Meaning	Swimmer Original Measured Values
1. Duration of Start Signal Reaction	Reaction to signal until first movement	0.16 s
2. Take-off Time	Reaction and leg action duration	0.68 s
3. Forward Speed & Time during Behind-leg Push	Rear leg power and forward body movement	1.67 m/s / 0.59 s
4. Forward Speed & Time during Front-leg Push	Effect of front leg pushing power	5.19 m/s / 0.09 s
5. Forward Speed & Time during Flight	Effect of power transfer from push to flight	5.10 m/s / 0.42 s
6. Arm Swing Max/Avg Pattern Speed & Length	Acceleration of arms using momentum	Max 8.84 m/s \| Avg 6.25 m/s \| Length 4.38 m
7. Average Head Speed during Flight	Effective use of gravity component	Vertical 3.3 m/s \| Horizontal 4.0 m/s
8. Length of Jump to Hand Entry	Jump efficiency without water resistance	3.5 m
9. Body Angle at End of Leg Push	Timing for best power transfer direction	+15°
10. Body Angle before Head Entry	Use of diagonal gravity component	-20°
11. Body Entry Angle Underwater	Depth and entry direction	40°
12. Body Entry Average & Pattern Speed	Streamlining quality during entry	Pattern 6.2–5.9–4.9 m/s \| Avg 5.7 m/s
13. Avg Underwater Speed during Entry	Use of gravity and forward speed	Vertical 3.0 m/s \| Horizontal 5.0 m/s
14. Underwater Kicks below 1 m Depth	Optimal depth control	5 kicks
15. Forward Speed & Length of Each Kick	Dolphin kick efficiency	1st: 2.5/0.8 \| 2nd: 2.32/0.8 m
16. Number of Underwater Kicks	Depth control and rising pattern	8 kicks
17. Kick Rate	Rhythm and frequency	Avg 184 kicks/min (188–176 range)
18. Vertical Speed of Each Kick	Kick pattern quality	Down 3.5–3.7 \| Up 2.1–2.5 m/s
19. Vertical Amplitude of Each Kick	Wave transmission amplitude	0.45–0.53 m
20. Forward Speed & Distance during Pullout	Efficiency of first pullout	1.9 m/s \| 1.0 m
21. Avg Hands Speed during Pullout	Catch–pull–push–exit quality	2.3 m/s
22. Speed, Distance & Time to Breakout	Overall start precision	2.1 m/s \| 12 m \| 5.6 s
23. General Start Efficiency (15 m)	Total start performance	6.0 s \| 2.5 m/s

3. Teaching & Corrections Architecture

3.1 Priority Sequence

Underwater dolphin structure and velocity maintenance
Entry streamline control
Take-off impulse mechanics
Breakout timing and stroke connection

3.2 Dryland Imitation

Streamline alignment rehearsal
Core-driven dolphin rhythm simulation
Arm pullout coordination practice
Explosive block push simulation

3.3 Special Technical Water Sessions

Underwater-only 15 m velocity sets
Dolphin frequency control drills
Breakout timing repetitions
Entry angle control exercises

3.4 Integration in Performance Training

Start execution within sprint intervals
Underwater control under fatigue
Velocity preservation inside race-pace sets

4. Creating Integrated Movement Image

Visual – video review of streamline and kick rhythm
Verbal – explanation of underwater kicking phase importance
Kinesthetic – perception of wave transmission through body using fixed hip
Acoustical – rhythm consistency

Video still-frame analysis verifies internal image: “Is streamline optimal?” “Is breakout at peak velocity?”

5. Full Self-Control Checklist

Underwater Phase

Was streamline maintained without knee drop?
Was kick frequency stable?
Did amplitude remain consistent?
Did velocity decrease before breakout?
Was breakout aligned with peak speed?

Entry and Transition

Was entry angle optimized for minimal resistance?
Was first dolphin initiated immediately?
Was double-arm pullout symmetrical?
Was first surface stroke integrated smoothly?

Global Evaluation

Did I win the start segment to 15 m?
Was the most important phase dominant?
Did secondary corrections disturb primary phase?

Complete quantitative and qualitative requirements, measuring parameter matrices, and detailed correction protocols of all 15 Models will be included in the Video Analyzer (Full Mode) Version.