Product Overview
ARK is a Sweden-born company focused on developing gear solely for swimrun. Products are tested by swimrunners in the Swedish archipelago, home to the sport of swimrun. The ARK Keel is the first, and currently only pull buoy offered by this company. [UPDATE: ARK released the PONTOON pull buoy in late 2019, their second pull buoy offering- we can’t wait to test and review this for ya’ll!] The Keel features a unique shape meant to minimize drag and maximize flotation. We tested this product in the pool, open water, and under race conditions at the 2019 Orcas Island Swimrun.
Disclaimer: Swimrun Labs did not receive any payment from ARK or its competitors to write this product review, and acquired the product through purchase at market value.
Specs
- Cost: $44.41 (+ $22.21 shipping to the U.S.)
- Weight: 172g (6.07 oz)
- Buoyancy effect: 46.1 Newtons
- Dimensions: 28 cm length x 26 cm height x 12 cm width
- Material: EVA foam
- Color: Black with white print
Initial Impressions
We were so excited when the ARK Keel landed on the doorstep. Its angular/geometric shape and aqua-dynamic design is unlike any pull buoy out there. It looks like the pull buoy of the future.
We immediately unwrapped it and placed it between our thighs. **Nuance alert!** This is when we discovered there is a top and a bottom to the Keel- it is not symmetrical like most pull buoys. The part between your thighs is slightly thinner at the top, gradually widening towards the bottom to ensure a more snug fit as people’s thighs tend to have more space between them moving towards the knees. While this is an elegant detail, it does make it important to consider when setting up the pull buoy for thigh attachment for racing. You have to select which thigh you want to attach it to and stick to it. If you want to place it on the opposite thigh, you have to reconfigure your attachment, so the thinner part is closer to your pelvis and not your knees.
Testing Results Breakdown
The ARK Keel is light weight and barely noticeable when secured around the thigh or lower back; however, it doesn’t come designed for thigh or low back attachment, so we had to configure this ourselves after a visit to the local hardware store. Also, while its size is beneficial for floatation in water, it becomes a little cumbersome on trail, especially single track. With it attached around the thigh, there were a handful of instances where it would hit trees and branches….throwing us a little off-kilter during those technical trail runs. This of course would be mitigated if worn on the back. For $10 ARK will configure the Keel for your thigh or back at races where they are present. (Note: At the time of this review, ÖTILLÖ Catalina Swimrun is the only US race where ARK is present.)
This is where the the ARK Keel really excels. At first try, it feels like you’re swimming downhill. It’s exhilarating! In pool trials this pull buoy cut 100-meter race pace time by 6 whole seconds when compared to the Finis pull buoy, and by 4 seconds when compared to the Elite Swimrun Pull Buoy.
This is most likely more to do with the DIY thigh attachment set-up than the pull buoy itself, but because of the size of the posterior part of the pull buoy, it was a little clunky placing it between the thighs when transitioning to the swim, and pulling it out when transitioning to the run.
Overall Summary
- Buoyancy
- Light-weight
- Aqua-dynamic design
- Value
- No race belt or thigh attachment
- Width more noticeable on single-track
- Cost to ship from Europe
Still not enough information? Look at our in-depth comparison of the ARK Keel to the top pull buoys used in swimrun competition.
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