Marathon Swimmers Federation To Test Stinger Suits

Marathon Swimmers Federation To Test Stinger Suits

Courtesy of WOWSA, Huntington Beach, California.

Two of the highest profile open water swimmers in contemporary times have used stinger suits: Australian Penny Palfrey during her 2010 unprecedented swim from Little Cayman to Grand Cayman in the Cayman Islands and American Diana Nyad from Cuba to Florida across the Straits of Florida in 2013.

In her 41 hour 6 minute 67.26-mile (108 km) Bridging The Cayman Islands swim, Palfrey used a stinger suit to protect herself from box jellyfish and other venomous marine life in the nighttime hours (see photo above as she walked onshore at the finish of her swim). During her 110-mile (177 km) Straits of Florida crossing of 52 hours 54 minutes, Nyad also used a stinger suit before dusk to past dawn that was designed by FINIS in order to protect herself against box jellyfish.

Now MSF co-founders Evan Morrison and Donal Buckley have proposed to test stinger suits. “We are proposing that MSF do some tests on (at least one) stinger suit and come to a transparent determination of and for the members here and extension the sport at large,” writes Buckley (here).

Their decisions and determination of the possible use of a stinger suit may have far-flung and long-term influences on the sport of marathon swimming as defined by the Marathon Swimmers Federation.

Testing will be done by Morrison in Aquatic Park in San Francisco, California where Morrison will have the assistance of other swimmers in the San Francisco Bay area who may test the stinger suit(s) for buoyancy and heat retention. Buckley writes, “The results of tests [will] be published [on the Marathon Swimmers Federation forum] here, and possibly a committee to decide the outcome and update the rules as appropriate.”

It will be influential in the sport of marathon swimming if the Marathon Swimmers Federation determines stinger suits are consistent with the spirit of marathon swimming and deemed acceptable as Standard Equipment. But it is merely one step in this process. As Morrison writes in the MSF Forum, “This issue needs to be clarified in the Rules, regardless of the insights gained from this test. The test won’t be a deciding factor, merely informative and interesting.”

Standard Equipment is currently defined as “one swimsuit made of porous, textile material. For males, the suit must not extend below the knee or above the waist. For females it must not extend below the knee, onto the neck, or beyond the shoulder.”

Most stinger suits are generally understood as protective swimwear made from porous, textile materials, but the suits extend past the knee to the ankles and beyond the shoulder to the wrists. It will also be interesting to see if the MSF determines if or not booties and gloves are an integral part of stinger suits – or separate pieces of equipment.

At the current time, stinger suits are defined by the Marathon Swimmers Federation as non-performance-enhancing equipment. This type of equipment is defined in the same category as rash guards, wildlife deterrents (e.g., shark shields, shark divers, and jellyfish sweepers), and wearable electronic devices that log data, but do not transmit it to the swimmer.

Without a doubt, swimmers like Palfrey and Nyad have used stinger suits as safety equipment. Because of the very real threat of being stung by some of the most venomous creatures on Earth, stinger suits offer unparalleled protection against various types of box jellyfish. Frankly, this protection can be the difference between life and death. “I have seen first-hand both Penny and Diana being stung just before dusk,” recalls Steven Munatones who has served on both women’s support crews. “It was terrible what they experienced. It was gruesome, inhuman really, because of the intensity of pain that they experienced. Both also clearly showed how incredibly courageous they are and the tremendous level of pain tolerance they can endure. My heart sank when the venom that entered their system caused a incomparable pain that I could not never imagine. How quickly and how physiologically they recovered from these stings is beyond comprehension.”

Other athletes have also experienced similar stings from the South Pacific to the Sea of Cortez. These athletes had to pull out of their swims due to the intensity and amount of venom that seeped into their system. Stinger suits are one possible answer. “I always think that swimmer safety overrides everything else,” Munatones says. “Penny’s encounters with jellyfish in the Kaieiewaho Channel in Hawaii and Diana’s initial swim [without a stinger suit] in the Straits of Florida convinced me that stinger suits were a necessity when these box jellyfish are present in the waters and something that should not be overruled in the sport of open water swimming. At the same time, stinger suits are purposefully and intentionally eliminating a natural element and obstacle of the natural environment – the stings of jellyfish, Portuguese man o war and other marine life.

The use of the stinger suit may also be judged against – or within – the concept of the spirit of marathon swimming as defined by the Marathon Swimmers Federation.” MSF’s rules state, “Marathon swimmers embrace the challenge of crossing wild, open bodies of water with minimal assistance beyond their own physical strength and mental fortitude. There are ways to make the sport easier, but marathon swimmers consciously eschew them. Marathon swimmers take pride that their achievements can be meaningfully compared to the achievements of previous generations, because the standard equipment of the sport has not changed significantly since 1875.”

At the same time, it is a fact that the porous material of stinger suits is much more difficult to swim in than traditional swimwear. “Stinger suits essentially weigh the swimmer down. Big-time. Their purpose is not to aid in buoyancy, propulsion, or heat retention; their intention is to protect against box jellyfish, Portuguese man o war, blue bottles, sea wasps and other venomous marine life. So while stinger suits are protective wear against some of the most venomous on the planet, they are also a built-in hindrance to swimming fast, swimming far, and even basic feels of buoyancy,” describes Munatones.

The Marathon Swimmers Federation may have various elements to consider when defining where stinger suits far within the realm of its definitions of Standard Equipment, Non-performance-enhancing Equipment, and Nonstandard Equipment for Marathon Swimming.

As accomplished marathon swimmer David Barra points out in the Marathon Swimmers Forum (here), there are issues of compression (that serve to reduce fatigue and promote muscle recovery), protection (from the elements and marine life), buoyancy, heat retention, and improved coefficient of friction. These issues, if judged to be true by MSF, are not consistent with the spirit of marathon swimming.

In my experience with various types of stinger suits including the type of stinger suit designed by FINIS, compression, buoyancy, and improved coefficient of friction are non-issues,” offers Munatones. “The materials used were the opposite of speed-enhancing. They caused greater efforts by the swimmer, made swimmers sink lower in the water, and are much less sleek and hydrophobic than human skin. But in terms of protection, without a doubt, the stinger suits are – bar none – the best thing around. In terms of heat retention, it would be my guess that a swimmer would be perhaps marginally warmer in a stinger suit than not, but that is only a guess. But then again, stinger suits are usually used in very warm water and air conditions, so hypothermia is generally not a key issue. It will be very interesting and educational to learn the outcome of the Marathon Swimmers Federation’s tests, conclusions and decisions.”

For the time being, the Marathon Swimmers Federation defines stinger suits as non-standard, non-performance-enhancing equipment. This means they must be declared specifically in the swim documentation, though they do not disqualify a swim from being considered unassisted.

The Federation could possibly take some clues on testing from FINA (Fédération Internationale de Natation), the world’s governing body for aquatics that always tests its competitive swimwear for coverage, material appropriateness, compression, buoyancy, and permability. FINA’s rules apply to swimwear to be used in FINA and Olympic Games pool and open water swimming competitions as follows:

Surface Coverage

• From June 1st 2010 FINA-approved open water swimwear for both men and women shall not cover the neck, extend past the shoulder, nor shall extend below the ankle. All open water swimsuits shall comply with the FINA Criteria for Materials and Approval Procedures.


• FINA-approved swimsuits are made of traditional permeable textile (i.e., open mesh material) material (such as cotton, Nylon, Lycra and the like) with no application of surface treatment closing the open mesh structure.

• Any variations in colour, shape and sizes shall not lead to any changes to physical or technical parameters of the material. The product consists of the basic construction features (such as the positions and numbers of seams on the different sizes or shapes).


• The wearing of the swimsuit shall not offend morality and good taste (in particular, but not exclusively, because of the cut of the suit and body parts exposure whether covered or not).

• Men’s swimsuits are in one piece. Subject to observance of the decency rule and limitations of the body surface covered, women’s swimsuits may be in one or two pieces. Other items covering the body that are not part of the swimsuit are prohibited.

• The material used for swimsuits can be only Textile Fabric(s). For the purpose of these rules, this is defined as material consisting of, natural and/or synthetic, individual and non-consolidated yarns used to constitute a fabric by weaving, knitting, and/or braiding.

• Any material added on to the surface of the textile fabric (e.g., coating, printing, impregnation) shall not close the open mesh structure of the base textile fabric. The treated material shall also comply with all requirements, particularly in regard to thickness, permeability and flexibility.

• The material shall be flexible and soft folding, and shall be regular and flat. The material shall not form outstanding shapes or structures, such as scales. No outside application shall be added on the material.

• Different materials may be used in one swimsuit provided they are textile fabrics as defined above; and they comply with all other criteria including thickness and permeability. Furthermore, combining materials shall not create any outstanding shape(s) or structure(s). Layered materials must be attached/ bound together except where required to protect sensitive parts (privacy layers).


• The total thickness of material/s used shall have a maximum value of 0.8mm with a tolerance of +/- 0.1mm according to ISO 5084. The thickness of layered materials is the total thickness of all layers are measured together. It is clarified that this maximum thickness does not apply to seams as far as the seams are functional, and their thickness and width result from their natural functions.


• The swimsuit shall not have a buoyancy effect above 0.5 Newton measured after application of vacuum with a tolerance of +/- 0.1Newton.


• Material(s) used must have at any point a permeability value of more than 80 liters/square meter/seconds (1/m2/2) with a tolerance of +/- 5% (in the range of Minimum Value). Permeability values are measured on material with a standard multidirectional stretch of 25%. However, measures on material which cannot be significantly stretched will be carried out on unstretched, flattened material. Permeability of layered materials is the permeability of layers measured together.


• No zippers or other fastening system is allowed. Seams shall be limited to functional systems and shall not create outside shapes. Use of seams (notably number, overall length, disposition) shall not affect compliance with the criteria set forth herein.

• The purposes of the seams are to join together the elements of the swimsuit (seams), to finish properly the swimsuit at its edges (edge seams), to prevent the swimsuit legs to roll back (grippers), to hold a jammer or brief (waistband), and to maintain the upper part of a women’s bodysuit (straps). The seams must be fit for the above purposes and shall have no other function. Excessive numbers of seams are prohibited. Permeability will not be tested on seams, provided they are considered as legitimate and functional seams.

External stimulation or influence

• Swimsuits which include any system providing external stimulation or influence of any type, including pain reduction, chemical/medical substance release, electro-stimulation, etc. are prohibited.

Swimsuits under FINA’s jurisdiction are not permitted to be customized in any way. “There shall be no variation/modification for individual swimmers from the Product corresponding to the Samples submitted to obtain approval,” are part of the rules governed by the FINA Swimwear Approval Commission that includes Professor Jan-Anders Manson, David Pendergast, Shigahiro Takahashi, and Bruce Mason.

Time will tell if stinger suits will be judged part of the sport – or not. Follow the Marathon Swimmers Federation discussion and determination here.

Photo above by Norma Connolly shows Penny Palfrey completing her Bridging The Cayman Islands swim.

Copyright © 2014 by World Open Water Swimming Association