5 Sets for Improving Underwater Dolphin Kick

Ready to power up your underwaters? Dive into our favorite swim sets for improving the underwater dolphin kick.

The underwater water dolphin kick is an essential component of swimming fast.

No matter what the stroke, distance, or pool type, an effective underwater fly kick is crucial for getting the most from your hard work in practice on race day.

While there are many ways to improve your underwaters, including simply doing more of them during your swim workouts to increased core training to the right dryland exercises, you should also be doing specific sets for underwater dolphin kick technique, power and conditioning.

Here are five swim sets to add to your swim training regimen to take your underwaters to the next level.

1. The Bread-and-Butter Dolphin Kick Set

This underwater dolphin kick set can be used in several different ways.

For swim workouts where something else is the primary focus (big threshold set, tons of race pace reps, etc), it’s a great way to get some quick UDK in and prime your legs and lungs to crush the main set.

You can also tweak it by adding resistance when you want to increase the power of your dolphin kick.

The set works underwater dolphin kicking on the front, back, and on both sides (also known as “Fish Kicking”).

Fun fact: The fastest way to dolphin kick for most swimmers is on their back.

Here is the set, feel free to adjust the interval as you please:

• 20 x 25 dolphin kick with swim fins on 40 seconds
• 5 rounds [25 – on the front, 25 – on the left side, 25 – on the right side, 25 – on the back]

As mentioned earlier, you can power up this set, too:

• For power and speed development: Increase difficulty by throwing light DragSox over your fins or strapping a swim parachute to your butt (not literally…). As you increase the resistance, however, extend the intervals for sufficient rest to maintain high power output.

I love this set for a multitude of reasons, but especially on days where my back and hips are stiff and sore, this is a great way to switch on “dolphin mode.”

2. Resisted Dolphin Kicking

To get faster at underwater dolphin kicking, you need to develop some power in your UDK.

That’s where this super simple and time-effective set comes in.

Researchers took a group of 32 elite, national-level competitive swimmers in Japan and had them perform a 4-month intervention that added a ~10-minute underwater dolphin kick set to their regular 9-10x workouts per week training routine.

By the end, the swimmers underwater kicking improved significantly in terms of velocity and tempo.

The men in the study increased average dolphin kicking speed from 1.73 m/s to 1.81 m/s, and the women fared slightly better, improving from 1.49 m/s to 1.53 m/s.

The underwater dolphin kicking set that they did during the intervention?

This:

• 200m butterfly kick, alternating 50m on the front, and 50m on back, focusing on undulation and kicking from the trunk.
• 4×5 all-out underwater dolphin kicks with short resistance tubing (full rest between efforts for maximum effort)

And that’s it!

The participants completed the set 2-4x per week for the duration of the intervention.

Straightforward, simple, and nails the essentials.

3. Vertical Kicking

Vertical kicking is a kicking drill where swimmers, as you can probably guess, set themselves up in a vertical position and kick to keep the head above water.

Part resistance training, part not-drowning!

Vertical kicking is excellent for improving lower body power, reducing excess knee bend, and encouraging swimmers to kick powerfully in both directions, upgrading the up- and downbeat phases of the dolphin kick.

It’s also an awesome core workout for swimmers as balancing yourself vertically and kicking powerfully lights up the muscles in the trunk.

See also: 8 Best Core Exercises for Swimmers

A study published in the Journal of Physical Education and Sport, titled “The impact of special strength intervention in water on the flutter kicking,” showed that a twice-a-week intervention of vertical kicking with experienced national level swimmers improved 50m kicking time 4.56-7.23% compared to a control group.

Vertical kicking is also awesome for swimmers dealing with a bout of swimmer’s shoulder or on days when the fast lane is packed with head-up breaststrokers.

Here are a couple of sample vertical sets for a stronger underwater dolphin kick:

• 10 rounds – [20 seconds dolphin kick – high tempo; 40 seconds rest]
• 20 rounds – [20 seconds dolphin kick with DragSox – 40 seconds rest]

4. Target the Upkick

Gary Hall Sr. is one of the legends both in the sport and for bringing sport science to the swimming masses.

Among the sets that he recommends for a stronger underwater dolphin kick is this simple set of 25s that is designed to help swimmers really hammer the upkick phase.

At the top of the upkick phase during dolphin kicking, a small vortex is created that serves as a “push-off” for swimmers to generate propulsion (Andersen and Sanders, 2018).

This set is to be done on the back with your favorite set of swim fins and a nose clip, if necessary:

• 20×25 underwater dolphin kick on your back, taking 10-15 seconds rest after each rep.

As Gary notes in his fantastic book Fundamentals of Fast Swimming: How to Improve Your Swim Technique, “focus on pressing down hard against the vortex with the bottom of your fins.”

5. The Eddie Reese Dolphin Kick 200s

Most swim fans don’t need an introduction to Eddie Reese, the man, the legend, the Longhorn.

Coach Reese won 15 NCAA championships coaching the Texas Longhorns, coaching countless elite swimmers, butterflyers, and dolphin kickers who won NCAA, World, and Olympic gold medals.

See also: 8 Tips for a Perfect Butterfly Stroke

Names like Joseph Schooling. Aaron Piersol. Ian Crocker. Neil Walker. And on and on and on.

(Reese was no slouch himself in the pool, winning a bunch of SEC titles swimming for the Florida Gators in the 1960s.)

In an interview with Brett Hawke in 2021, Reese talked about the importance of working the underwater dolphin kick.

The main set he used for giving his swimmers a faster and more powerful underwater dolphin kick?

Here it is:

• 5×200 butterfly kick on your back with swim fins on 3:00
• Go Fast!
• 6 underwater dolphin kicks off each wall, in a streamline
• The rest of the length is done butterfly kick on your back, arms at the side

Reese likes this set as it “allows a greater range of motion so there is more involvement of the abs and the quadriceps.”

This fly kick set is a great meat-and-potatoes option for racking up a ton of yards or meters of higher-intensity dolphin kicking with great technique.

Done repeatedly over the course of the season, it is also a great test set that gives you metrics to improve upon as the weeks, months, and fly kick reps stack up.

Wrapping It Up

The real secret to developing a killer underwater dolphin kick lies in doing it more often in training.

Adding just one dolphin kick off each wall, for example, over the course of a 4,000m swim workout would yield an additional 160 dolphin kicks.

That said, dropping some specialized dolphin kick sets also gives you a chance to give it total focus.

Ultimately, the more dolphin kicking you do, the better you will get at it.

As Coach Reese says, “You’re a product of what you do.”

More Swim Workouts

Looking for more swim workouts to crank up your performance in the pool?

We’ve got you covered:

• 6 Sprint Swim Workouts for Bringing the Thunder
• 7 Kick Sets for Swimmers
• 5 Swimming Workouts You Can Do in 30 Minutes or Less

Disclaimer: Remember, before kicking off a new swim workout regimen or engaging in vigorous exercise, it’s always wise to consult with a healthcare professional to ensure it’s the right fit for you.

ABOUT OLIVIER POIRIER-LEROY

Olivier Poirier-Leroy is a former national-level swimmer. He’s the publisher of YourSwimBook, a ten-month logbook for competitive swimmers.

He’s also the author of the recently published mental training workbook for competitive swimmers, Conquer the Pool: The Swimmer’s Ultimate Guide to a High-Performance Mindset.

It combines sport psychology research, worksheets, anecdotes, and examples of Olympians past and present to give swimmers everything they need to conquer the mental side of the sport.

Ready to take your mindset to the next level?

Click here to learn more about Conquer the Pool.