Why is kicking above water generally inefficient?

Kicking above the water is inefficient because pushing against air provides negligible propulsion, wastes energy, increases drag, and can disrupt a swimmer's streamlined body position.

What are the key characteristics of an ideal, efficient swim kick?

An ideal swim kick originates from the hips, utilizes flexible ankles for a fin-like action, has a small vertical amplitude, and involves continuous motion both up and down.

Is it ever acceptable for a swimmer's feet to break the water's surface?

While the goal is a submerged kick, a slight disturbance or "boil" on the surface, where toes or the top of the foot may occasionally break through, can be a byproduct of a strong, efficient kick, but it's not the primary goal.

How can a swimmer improve their kick for better efficiency and power?

Swimmers can improve their kick by focusing on ankle flexibility, initiating power from the hips, maintaining a small and continuous amplitude, engaging their core, and practicing with tools like kickboards and fins.

Is kicking above water efficient when swimming?

Q: What is the primary purpose of the swim kick?

The swim kick primarily serves to provide propulsion and, more critically, to maintain balance and optimal body position in the water, keeping the hips high to reduce drag.

Should you kick above water when swimming?

While it might appear that a swimmer's feet break the surface of the water during an efficient kick, the primary propulsive phase of the kick should occur beneath the water's surface. Kicking above the water is generally inefficient and counterproductive.

Understanding the Biomechanics of the Swim Kick

The swim kick, particularly the flutter kick in freestyle and backstroke, is a complex motion involving the hips, knees, and ankles. Its primary roles are to provide propulsion and, perhaps more critically, to maintain balance and optimal body position in the water. An effective kick is an extension of the body's core, with power originating from the hips and transferring smoothly through the legs to the feet.

The "Above Water" Kick: What Does It Mean?

When people ask about kicking above water, they often refer to a highly visible, splashy kick where a significant portion of the foot or even the lower leg breaks clear of the water's surface. This observation can stem from seeing elite swimmers whose feet do occasionally break the surface, leading to a misconception that this is the goal. However, the intent of an efficient kick is never to propel oneself by pushing air.

The Purpose of the Swim Kick

The swim kick serves two vital functions:

Propulsion: While the arms typically generate the majority of forward propulsion (around 80-90% in freestyle), the legs contribute significantly, especially during sprints or when maintaining high speeds.
Body Position and Balance: A continuous, well-timed kick helps keep the hips high in the water, reducing frontal drag and allowing the body to rotate effectively during the stroke cycle. Without an effective kick, the lower body tends to sink, creating a "downhill" swimming posture that increases resistance.

The Ideal Kick: Submerged and Propulsive

An efficient and powerful kick is largely executed beneath the water's surface. Key characteristics include:

Origin from the Hips: The kick should be driven primarily from the hips, with a relatively straight leg, allowing for a full range of motion.
Flexible Ankles: Dorsiflexion (pointing the toes) is crucial. Flexible ankles allow the foot to act like a fin, creating a larger surface area to push against the water.
Small Amplitude: The vertical motion of the kick should be relatively small, typically within the shadow of the body. Over-kicking with a large amplitude wastes energy.
Continuous Motion: The flutter kick is a continuous, alternating up-and-down motion, ensuring constant pressure on the water. Both the up-kick and down-kick phases contribute to propulsion.

Why Kicking Appearing Above Water Can Happen (and why it's not the goal)

While the goal is a submerged kick, it's common for a swimmer's feet to break the surface. This is often an indication of:

Poor Ankle Flexibility: Stiff ankles prevent proper "fin" action, leading to a less effective push against the water and more surface disruption.
Over-Kicking or Large Amplitude: Kicking too powerfully or with too much vertical motion can cause the feet to pop out of the water. This expends excessive energy without proportional gain in propulsion.
Sinking Hips/Poor Body Position: If the hips are too low, the swimmer might instinctively kick harder or higher to try and elevate the lower body, leading to an "above water" appearance.
Lack of Core Engagement: A strong core helps maintain a streamlined body position. Without it, the body might undulate excessively, causing the legs to flail.
Incorrect Timing: A kick that is out of sync with the arm stroke can disrupt rhythm and body position.

The Detrimental Effects of an Over-Exaggerated "Above Water" Kick

Kicking excessively above the water's surface has several negative consequences:

Wasted Energy: Pushing against air provides negligible propulsion. The energy expended in lifting the legs out of the water is energy not used for forward motion.
Increased Drag: Kicking above the water creates splash and turbulence, which can increase drag on the body. A chaotic kick also disrupts the clean flow of water around the body.
Disrupted Body Position: A large, splashy kick can cause the hips to drop, leading to a less streamlined position and more resistance.
Reduced Propulsion: The propulsive force comes from pushing water backward. When the feet are in the air, they cannot effectively generate this force.

When is Some Water Disturbance Acceptable or Unavoidable?

It is important to differentiate between an inefficient "above water" kick and the natural surface disturbance of an effective kick. In a powerful flutter kick, especially during sprints, the top of the foot or the toes may occasionally break the surface, creating a "boiling" or "frothy" appearance. This is generally a byproduct of a strong, continuous kick with good ankle flexibility, where the power is primarily exerted under the surface, and the subsequent upward motion causes a ripple or slight breach. This is not the same as deliberately kicking high out of the water.

Optimizing Your Kick for Efficiency and Power

To develop a more effective and efficient kick:

Focus on Ankle Flexibility: Regularly stretch your ankles to improve dorsiflexion. This is perhaps the single most important factor for an efficient kick.
Initiate from the Hips: Ensure the power comes from your glutes and hamstrings, not just your knees. Keep your legs relatively straight, with a slight knee bend on the up-kick and down-kick.
Small, Continuous Amplitude: Aim for a kick that stays largely within the "shadow" of your body, about 12-18 inches in vertical displacement.
Engage Your Core: A strong core helps maintain a stable, streamlined body position, allowing your legs to kick more effectively without causing your hips to sink.
Practice with a Kickboard: Use a kickboard to isolate your kick and focus purely on technique. Pay attention to how much water you are "holding" and pushing with your feet.
Utilize Fins: Short-blade fins can help you feel the water pressure on your feet and develop better ankle flexibility and leg strength.

Conclusion: Focus on Propulsion, Not Splash

In summary, while it's common to see a slight disturbance or "boil" on the water's surface from an efficient kick, the goal is never to actively kick above the water. An effective kick is primarily a propulsive force generated beneath the surface, contributing to forward momentum and maintaining a high, streamlined body position. Swimmers should prioritize developing flexible ankles, strong core engagement, and a continuous, small-amplitude kick that maximizes water contact and minimizes wasted energy. Focus on feeling the water and pushing it backward, not on making a splash.

Swim Kick: Understanding Efficiency, Biomechanics, and Optimization