Underwater Kick Body Alignment: The Complete Guide

Why Alignment Is Critical for Your Underwater Dolphin Kick

The reason underwater dolphin kick is so fast, even though you aren’t using your arms at all, is because the amount of drag is so much less underwater than at the surface. You generate speed by creating more propulsion than resistance. The more you reduce the resistance, the more you increase the speed.

The added benefit of increasing speed by eliminating resistance is that it doesn’t cost you as much energy. To create more propulsion, you have to use more energy. If you’re able to create less resistance through better alignment, you’ll need less energy to create the same amount of speed.

Why does that matter for underwater kick? Think about your last turn during a race and how hard it is to push off with a strong effort. If you can use less energy throughout your race because you’re creating less resistance, you’ll have more energy available during your last turn to go fast.

Of course, just because you’re in a lower-resistance environment under the water doesn’t necessarily mean that you’re creating less resistance. Your goal is to get into postures and positions that keep the resistance as low as possible to take advantage of the opportunity kicking underwater presents.

How can you keep resistance as low as possible? There are two key skills that you’ll want to perfect:

1. Find an optimal range of motion with your undulation.
2. Control your spinal position, so you’re moving as straight through the water as possible.

Good Alignment for Underwater Dolphin Kick Starts With Stability

The starting point for effective underwater dolphin kick is learning to control your upper body. If you can’t control your upper body, you’ll have a hard time keeping resistance low. Your hands, head, and shoulders are the first parts of your body to face the water when you dive in or push off the wall. If they’re moving up and down or left and right without any intention, you’ll experience a lot of resistance as you move through the water. But if you can control the motion, you’ll be able to keep resistance low. A good sports car leads with a streamlined surface area. This same should be true of your underwater kick.

Because you’re moving through a fluid without any solid anchor points, controlling your body can be difficult, especially when you’re trying to undulate back and forth at a high rate. Choosing how much you want to undulate and the position of your body, particularly your spine, is difficult. Choose an optimal amplitude and maintain a straight body line to keep resistance low. Finding stability makes achieving both easier.

Stability doesn’t mean your upper body doesn’t move. It’s not about creating zero movement or even small amounts of movement. It’s about creating controlled movement. The ability to control your upper body to keep resistance low and start an effective kick is foundational for creating speed underwater. It can help to limit movement at first to really understand stability. Once you understand the concept, widening your range of motion can be effective provided you remain in control of your body.

Variations in Upper Body Ranges of Motion During the Underwater Dolphin Kick

Stability isn’t the same as rigidity. Your hands and upper body will move in a rhythmic manner that limits resistance and facilitates an effective undulation of your body. They’re not staying still, but they are in control. Once you learn to create stability, you can explore the optimal range of motion that you want to use with your upper body.

Some elite underwater dolphin kickers use a very small range of motion in their upper body. Some who are just as fast use a very large range of motion in their upper body. Both groups of swimmers move over that range of motion with control. 

Is one approach better than the other? No and yes. 

Both approaches can be effective in that the best underwater kickers in the world may have a small range of motion or a large range of motion in their upper body. It doesn’t seem to matter. But it does seem to matter on an individual basis. If you made swimmers with the largest ranges of motion use a small range of motion, they’d likely be slower. And the same is true if you forced swimmers with a small range of motion to move through a large range of motion. The key is finding what’s optimal for you.

The most effective way to learn stability is to greatly limit the range of motion you go through with your upper body. Once you understand the concept, you can explore larger ranges of motion with your upper body while still maintaining your control and stability. You may find that your underwater kick feels best with limited upper body movement. You may find that your underwater kick feels best with more upper body movement. Both strategies can be successful. 

Respect the process. If you try to use big ranges of motion without having stability, you’re going to struggle. But once you learn control, those ranges of motion can be very effective for you.

The Importance of Spinal Alignment During Underwater Dolphin Kicks

Torpedoes are straight because that allows as much speed as possible through the water. The same concept applies to you and your underwater dolphin kick. The straighter you can keep your vessel (your body), the less resistance you create. Although you’re going to undulate when you do underwater kick, the basic vessel you’re undulating around should be as straight as possible. Large curves in your back are going to add resistance that ultimately will slow you down.

There are two curves in your back that have the potential to slow you down: a rounded upper back and an arched lower back. Unfortunately, these two issues can be related. The more rounded your upper back is, the more you have to arch your lower back to get into a streamline with your arms. The more you can smooth out these curves, the faster you can go.

We’re talking about ideals here, of course. Because of range of motion limitations, you may struggle to reduce the curvatures of your upper back and lower back while kicking underwater.

There are two options here:

1. Make the most of what you’ve got and work on your skills to create as much speed as your body allows. In other words, do the best you can with the physical tools you have. 
2. Work on land to address range of motion limitations to make it easier reduce curvatures. This takes work but will increase your potential to create speed underwater. If you’re like most swimmers, working on your mobility will help your underwater kick.

Finding the Best Amplitude for Your Underwater Dolphin Kick

Once you have control of your upper body and you have an awareness of the position of your spine, the next step in keeping your resistance as low as possible is optimizing the amplitude of your kick itself. 

The amount of range of motion your upper body goes through isn’t the same as the amplitude of your underwater dolphin kick. Swimmers who use a very small upper body motion can still move through a relatively large range of motion in their kick itself. And swimmers with a large upper body range of motion don’t necessarily use a larger range of motion with their kicks.

Achieving the best amplitude with your kick is all about trade-offs. 

• At one extreme, a really small, tight kick isn’t going to create much resistance as you move through the water. That’s great. The problem with really small kicks is that they aren’t going to create much propulsion either. Your legs need to move through the water to create speed. 
• At the other extreme, a really big kick helps you create more propulsion, but it’s also going to create a lot more resistance. And with a really big kick, the amount of resistance you create is going to be a lot larger than the amount of propulsion you create.

Find the best kick range of motion for you. The goal is to keep resistance as low as possible while creating as much propulsion as possible. Creating speed by keeping resistance low requires a lot less energy than creating speed through more propulsion. The best range of motion differs for each person. The key is to do drills that help you figure it out. And when in doubt, keep resistance low to make kicking underwater easier. 

Torso Range of Motion Versus Leg Range of Motion While Doing Underwater Dolphin Kicks

A key consideration in keeping resistance low and optimizing undulation is the difference between body range of motion and leg range of motion. 

To maximize speed, use underwater dolphin kick strategies that control your torso range of motion and increase your leg range of motion. The more you can keep torso range of motion controlled, the more you can limit the amount of resistance you’ll create as you move through the water. 

Why does it matter? The more torso range of motion you use when you kick, the more resistance you’ll create. But that extra range of motion doesn’t necessarily lead to more propulsion. By using a bigger torso range of motion, you’re getting more of the negative effects without more of the positive effects. Control your torso range of motion.

In contrast, going through a large range of motion with your kick allows you to move a lot more water over a much bigger range of motion. To cover that range of motion, you’re going to have to kick fast. That all adds up to faster underwater kick. Even if you’re creating more resistance with your legs, you’re creating so much propulsion that it still results in more speed.

A key aspect of creating propulsion is kicking so that your feet move well in front of your torso. This allows you to create more propulsion without a ton of resistance. Many elite underwater kickers are able to do a kick that has a big range of motion without using a big range of motion through their torso. They maximize speed by optimizing the amount of propulsion and resistance they create.

Common Body Alignment Mistakes While Doing Underwater Dolphin Kick

The common mistakes associated with bad alignment and increased resistance while doing underwater dolphin kick are all related to key skills:

1. Failing to maintain stability and control in your upper body. You need to have control of your hands, head, and upper body and keep them stable. If they’re moving all over the place, you’re going to create a lot of resistance and make every other skill more difficult. Learning to keep your upper body stable will allow you to do every other skill more effectively.
2. Failing to move through the water with great spinal alignment. You want to move through the water with great alignment of your spine. If you’re hunched over underwater with a rounded upper body or arched lower back, you’re going to create more resistance than necessary. The goal is to be as straight as possible, like a torpedo, to keep resistance as low as possible. 
3. Failing to use an optimal range of motion throughout your underwater kick. If your kick is too big, you’re going to create more resistance than necessary. At the same time, if your kick is too small, you’ll compromise the amount of propulsion you create as you move through the water. Finding your sweet spot is key for creating speed.

If you’re making all these mistakes, you’re going to create a lot of resistance as you move through the water. That makes going fast very difficult, even if you have a powerful kick.