How to Improve Your Ankle Mobility to Handle Swimming with Fins

Many people start swimming with fins and are initially surprised by the pain in their feet and ankles. Ankle mobility is the root cause of pain when it comes to swimming with fins, which requires both practice and stretching. It typically takes 3-4 weeks to feel like you can finish a swim with fins workout without such discomfort in the feet and ankles. This is one of several reasons we recommend adding mobility training to your workouts.

You can do this swim workout any day of the week. However, we tend to use this one to "top off leg day." It takes about 30 minutes and is nonstop swimming. This uses an easy recovery method that keeps you moving so you do not have to stop. It is called "turtle-backing."

Use a pair of fins -- either easy slip-on fins if you are new to swimming or scuba fins if you dive or are preparing for military special operations diving programs. Eventually, it would be best to use a bigger fin, such as those used in scuba diving. The military uses rocket or jet fins in their dive school training. Working through the initial pain long before you start these schools is good, as the learning curve takes a few weeks.

This is how to get used to the ankle pain that typically follows a few hundred yards of swimming with fins. This workout progressively builds strength in the hips and legs and slowly works the mobility in the ankles. Ankles take significant torque from the fin as it hyper-stretches each kick.

This is the workout:

Repeat 10-20 times (depending on your abilities):

• Swim 75 meters Combat Swimmer Stroke (CSS) or freestyle with fins
• Swim 25 meters turtleback
• No rest. You can catch your breath with the turtleback.

If you are set up in a long course (50-meter pool), try the following version:

Repeat 10 times.

• Swim 150 meters CSS or freestyle with fins.
• Swim 50 meters turtleback.

Here is a video description of the workout: Swim with Fins with Turtle-Backing Recovery

This is a solid way to get 1,000-2,000 meters of finning experience, as you may find that you cannot finish the workout because of ankle pain. If this occurs, take the fins off and replace the workout with the following 50/50 Workout:

Repeat five times (no fins).

• Swim 50 meters freestyle.
• Swim 50 meters CSS or breaststroke.
• Rest and stretch legs as needed.

Once your ankles start to feel better, try the fins again. This process will build both durability and mobility in the ankles, which are needed to be able to scuba dive for long periods and to do longer, open-water swims later in your training.

Take your swimming to new levels by adding one or two fin workouts per week if you like to swim as your primary cardio. However, if you are preparing to go to military special ops diving or rescue swimming schools, you must build up your ankles and legs to handle long swims with big fins. Start small, increase size and distances, and put on the bigger fins when ready to power through tides and currents of open water, swimming and diving.

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