Which of these hand positions is the best for swimming? Read on to find out.

Think about the last time you stuck your hand out the window of a moving car and played with the wind. As you changed the shape, angle and position of your wrist and fingers, you could feel the pressure of the wind change. The same concepts apply to your hand shape underwater.

The goal while you’re swimming is to create the largest surface area with the fingers, thumb and palm. The larger the paddle is, the greater the pulling force that can be applied during each stroke. Creating the largest paddle possible isn’t just about flattening the fingers and thumb together.

Here’s a quick refresher on fluid dynamics to explain why hand position actually matters:

As a solid object moves through the water, the layer of water next to it moves as well.

This “sticky” layer of water increases surface area of the object.

The force of the water will slightly flatten the skin on the fingers, creating a webbed effect.

Using computer simulations, scientist Alberto Minetti found the optimal spacing between fingers for swimming is 3–8mm, or roughly the natural distance between fingers when relaxed. By maintaining a slight spread between fingers, the surface area of the hand increases as it moves through the underwater pull phase.

Based on the learning above, it’s now easier to rule out improper hand positions. A cupped hand (option A) greatly reduces the overall size of the paddle. Wide fingers (option B) also lose surface area by allowing water to slide through the large gaps. Squeezing the fingers and thumb tightly together (option C) uses unnecessary muscle energy and also creates a loss of potential surface area. Option D shows a flat hand with small gaps between each finger and the thumb facing the same direction, slightly adducted next to the palm. This is the optimal hand shape because it creates the largest surface area during the pull.

RELATED: Maximize The Power Of Your Pull

Check Your Hand

Incorporate sculling drills to try different hand shapes.

Take a head-on underwater video to see your current hand shape.

Stick your hand out the window and play with the wind on the way to swim practice.

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