Starting Block Dive vs. In-Water Start: Technical Choices and Competition Rules Explained

Introduction

The start is the zero moment of every swimming race. A good start allows a swimmer to build an advantage from the very beginning; conversely, a poor start may force you to spend the entire race trying to catch up. For most swimmers, the potential for improvement in starting technique often exceeds their imagination.

Platform starts and in-water starts have clearly defined applications under the rules: freestyle, butterfly, and breaststroke use platform starts, while backstroke uses an in-water start. Understanding the technical essentials of both starting methods is especially important for all-around swimmers.

Platform Start: Technical Breakdown

Modern competitive starts use the “grab start” or the “track start,” with the latter currently being the preferred choice for most swimmers.

Track Start Steps:

1. Initial Stance: Grasp the front edge of the starting block with both hands, with one foot at the front of the block and one foot at the back (similar to a track sprint start)
2. Set Position: Raise the hips, shift the center of gravity forward, keep the head low, and look at the water
3. Takeoff: Drive forcefully off the block with the rear leg, swing both arms forward, and launch the body into the air
4. Flight Phase: Keep the body streamlined, tuck the head between the arms, and enter the water at an angle of approximately 30–40 degrees
5. Entry: Enter the water hands-first, maintain a streamlined body position, perform a dolphin kick until speed drops, then begin the first stroke

Track Start vs. Grab Start Comparison:

The Key to the Flight Phase of the Start

Many people believe that jumping high or jumping far makes a good start, but in reality, the entry angle is the most important control target during the flight phase.

The ideal entry angle is approximately 30–40 degrees, allowing the swimmer to reach the optimal propulsion depth below the surface (approximately 0.5–0.8 meters)—not too deep (which increases the time needed to rise) and not too shallow (which creates excessive splash and drag).

Underwater Actions After Entry:

• Maintain a streamlined glide
• Perform a dolphin kick until speed approaches swimming speed
• In freestyle, begin the first stroke approximately 10–15 meters after entry (or when nearing the surface)
• Rule requirement: the head must break the surface before the 15-meter mark

In-Water Start: Backstroke Technical Breakdown

The backstroke in-water start is the most technically complex start among the four strokes, as swimmers must generate force from a stationary position in the water with their back against the wall.

In-Water Start Steps:

1. Starting Position: Grasp the starting block (or wall-top) handrails with both hands, place both feet on the wall below the water surface, with knees bent
2. Set Position: Lift the hips out of the water, arch the body into a taut position, and prepare to push off the wall
3. Wall Push-Off: Drive forcefully off the wall with both legs, swinging both arms upward and backward
4. Flight and Entry: Arch the body backward, enter the water hands-first, with the head tucked tightly between the arms
5. Underwater Actions: Maintain speed with a dolphin kick, then surface and begin stroking before the 15-meter mark

Common In-Water Start Problems:

Foot Placement Height on the Wall for the In-Water Start

This is the most subtle technical detail in the backstroke start. The position of the feet on the wall affects the direction of the push-off force:

• Feet too high (near the waterline): The body arcs upward significantly after the push-off, the entry angle is steep, and the underwater glide position is shallow
• Feet at moderate height (approximately 30 cm below the waterline): The force direction is angled backward, the flight arc is good, and the entry depth is moderate
• Feet too low: The push-off force is dispersed, failing to fully utilize leg explosive power

Practical Recommendations

• Track Start Practice: First practice the push-off motion on land to familiarize yourself with the feeling of weight transfer, then practice in the pool.
• Timing Start Efficiency: Measure the time and distance from the start to the first stroke, using this as a quantitative indicator for start training.
• Underwater Dolphin Kick Strengthening: Regardless of the start type, the quality of the underwater dolphin kick directly determines the effectiveness of the start and should be a regular training item.

Conclusion

Improving starting technique requires repeated practice and attention to detail, but the payoff is substantial. A perfect start not only provides a speed advantage but also builds psychological confidence, leading to a better overall race performance. Treating the start as an independent technical module in training is one of the most efficient ways to improve competitive results.

Related Reading

• Swimming Start Technique: Speed Differences Between Grab Start and Track Start
• Start Technique: Comparison of Grab Start, Track Start, and In-Water Start
• Competitive Start Technique: Grab Start vs. Track Start
• Swimming Race Start Technique: Details and Improvement Methods for the Grab Start