Butterfly Stroke: Dive Start, Underwater Phase, and Training

Do you dive for butterfly?

Yes, in competitive swimming, the butterfly stroke universally begins with a dive start from the blocks, followed by a critical underwater phase of dolphin kicks before breaking out into surface swimming.

Understanding the Swim Start

In competitive swimming, the start is a foundational element that can significantly impact race performance across all strokes. It involves a powerful launch from the starting blocks (or wall in backstroke), followed by an immediate transition into the water designed to generate maximum initial velocity while minimizing drag. This initial phase sets the tone for the entire race, and for strokes like freestyle, breaststroke, and butterfly, it invariably begins with a dive.

The Dive for Butterfly: An Essential Beginning

For the butterfly stroke, a dive start is not only standard but crucial. Swimmers execute a forward dive from the blocks, aiming for a clean entry into the water. The objective of this dive is to:

• Generate Initial Momentum: Propel the swimmer forward with high velocity.
• Achieve a Streamlined Entry: Minimize splash and resistance upon entering the water.
• Transition Seamlessly: Set up the powerful underwater dolphin kick phase.

A well-executed dive involves a strong push-off from the blocks, a compact body position in the air, and a "spear-like" entry with the hands locked together, arms extended overhead, and head tucked between the arms, creating a tight, bullet-like shape.

The Underwater Phase: Dolphin Kicks and Streamline

Following the dive, the swimmer does not immediately begin surface swimming. Instead, they transition into a highly efficient underwater phase, which is particularly vital for the butterfly stroke.

• The Streamline: After entry, maintaining a tight, hydrodynamic streamline is paramount. The body remains rigid, arms extended, head neutral, and legs together. This position reduces frontal drag, allowing the swimmer to glide efficiently.
• The Dolphin Kick: This is the primary propulsive force during the underwater phase. The dolphin kick involves a powerful, undulating motion originating from the core and hips, propagating through the legs and feet. It's a full-body wave, not just a leg kick. Each kick generates significant thrust, propelling the swimmer forward.
• Number of Kicks: FINA (Fédération Internationale de Natation) rules permit swimmers to travel up to 15 meters underwater after the start and after each turn before they must break the surface. Swimmers strategically use a series of powerful dolphin kicks to maximize this underwater advantage, as it is often faster than surface swimming. The number of kicks varies based on the individual swimmer's power, technique, and race strategy.
• The Breakout: The breakout is the transition from the underwater phase to surface swimming. It requires precise timing, typically involving the first arm pull of the butterfly stroke coinciding with the final upward thrust of the dolphin kick as the swimmer reaches the surface.

Biomechanics of the Butterfly Start and Underwater Phase

The effectiveness of the butterfly start and subsequent underwater phase is rooted in precise biomechanical principles:

• Force Generation (Dive): The initial drive from the blocks utilizes the stretch-shortening cycle in the powerful muscles of the lower body (quadriceps, glutes, hamstrings) to generate maximal horizontal force.
• Hydrodynamics (Streamline): The streamlined body position minimizes the coefficient of drag. Any deviation, such as a dropped head or splayed fingers, increases drag and slows the swimmer.
• Propulsion (Dolphin Kick): The dolphin kick is a prime example of Newton's third law (action-reaction). The downward and upward motion of the body and legs pushes water backward, generating an equal and opposite forward thrust. This undulating motion is most efficient when initiated from the core, maximizing the contribution of larger muscle groups.
• Muscles Involved:
  • Dive: Glutes, quadriceps, hamstrings, gastrocnemius (calf muscles).
  • Streamline: Core stabilizers (rectus abdominis, obliques, erector spinae), latissimus dorsi, deltoids, triceps (to maintain arm position).
  • Dolphin Kick: Core muscles are paramount. Also, hip flexors/extensors, quadriceps, hamstrings, and gastrocnemius.

Training Considerations for an Effective Butterfly Start

Optimizing the butterfly start and underwater phase requires a multi-faceted approach to training:

• Strength Training:
  • Leg Power: Squats, lunges, box jumps, and plyometrics enhance the explosive power needed for the dive.
  • Core Stability: Planks, Russian twists, and medicine ball exercises strengthen the core, crucial for both streamline and dolphin kick power transfer.
  • Shoulder Mobility & Stability: Exercises targeting rotator cuff muscles and scapular stabilizers improve arm extension and streamline integrity.
• Technique Drills:
  • Streamline Drills: Practicing holding a perfect streamline position off the wall and from dives, often with fins to focus on body position.
  • Underwater Dolphin Kick Drills: Performing extended underwater kicking sets, with and without fins, focusing on rhythm, undulation, and efficiency.
  • Breakout Drills: Practicing the transition from underwater kicking to the first stroke, ensuring a smooth, powerful launch to the surface.
• Timing and Rhythm: Consistent practice is needed to develop the feel for the optimal number of kicks, the depth of the glide, and the precise timing of the breakout.

Common Mistakes and How to Correct Them

Even experienced swimmers can make errors that compromise the effectiveness of their butterfly start:

• Poor Streamline:
  • Mistake: Head out of alignment, arms not fully extended, hands separated, or a "banana" back.
  • Correction: Focus on squeezing the ears with the biceps, locking thumbs together, engaging the core, and keeping the body rigid. Use video analysis.
• Ineffective Dolphin Kick:
  • Mistake: Kicking from the knees, lack of hip drive, or insufficient undulation.
  • Correction: Emphasize initiating the kick from the chest/hips, focusing on a full-body wave. Use a snorkel to focus on body position without worrying about breathing.
• Premature Breakout:
  • Mistake: Breaking the surface too early, sacrificing valuable underwater speed.
  • Correction: Practice pushing the 15-meter limit. Use underwater markers or a coach's feedback to gauge distance.
• Lack of Power from the Blocks:
  • Mistake: Weak push-off, resulting in a shallow dive and reduced initial velocity.
  • Correction: Incorporate plyometric and strength training for leg power. Practice explosive starts, focusing on a powerful jump forward, not just upward.

Conclusion

The answer to "Do you dive for butterfly?" is unequivocally yes. The dive is the explosive gateway to the butterfly stroke, immediately followed by the critical underwater dolphin kick phase. Mastering this initial sequence – from the powerful push-off and clean entry to the efficient streamline and propulsive dolphin kicks – is fundamental for competitive butterfly swimmers. It represents a complex interplay of force generation, hydrodynamics, and precise technique, all contributing to a faster, more efficient race.