Frequently Asked Questions and Best Practices for MSF Documented Swims

Can my swim be crewed, observed/documented, and piloted/navigated all by a single person?

No. Although we are sympathetic with the manpower challenges and expense of marathon swimming, MSF Documented Swims require at least two people to assist the swimmer to cover the three critical roles involved with supporting the swimmer. One role is observer, the second is navigator/pilot/kayaker who charts the course, and the third is the crew who feeds the swimmer. How these roles are assigned across a two-witness event should be based on safety considerations and common sense. If a third person is available, that’s considered ideal because then each role can be given primary attention by the individual performing it.

The reason these roles are split across multiple individuals is because each requires specific skills and attention. It would be unsafe (and impractical) for the pilot or kayaker to be required to also observe a swim. In some instances, the kayaker charts the course and feeds the swimmer simultaneously, but they cannot also act as the official observer, not only for safety reasons, but also because of the potential for a conflict of interest. If the official observer - who is intended to be an independent, impartial witness to the swim - is also invested in feeding and guiding the swimmer, their objective independence may falter.

Generally speaking, the more witnesses there are to a swim, the greater the credibility of the claims.

Can I use a video camera as my independent observer/documenter of my swim?

No. Although digital media technology improves every day, we believe it will never be able to completely replace an experienced observer. This independent witness can comment on potential infractions and issues that a camera may not show. Also, GPS devices and video cameras are notorious for failing partway through a swim, and because of this unreliability, raw footage of a swim is not considered authoritative enough to substantiate claims submitted for MSF Documented Swim status as a standalone source. Video is a wonderful secondary substantiation of a swim when submitted with a thorough observer’s report from an objective, impartial witness to the swim.

I noticed that GPS tracking data are required for all MSF Documented Swims starting this year (2017). But what if I don’t own a SPOT tracker and/or can’t afford one? And what if the tracker fails midway through the swim? Will you not ratify my swim due to a technology failure out of my control? That seems unfair.

SPOT trackers are nice, because they provide real-time public tracking. But you don’t need a SPOT tracker to record a GPS track. Any Android or Apple smartphone, or GPS-enabled fitness watch (e.g., Garmin, Suunto, Apple Watch), serves as a perfectly good GPS track recording device. See this article for details.

GPS trackers do sometimes fail. Therefore it is always advisable to utilize multiple trackers on events where GPS data are critical for documentation. Redundancy vastly reduces the chances you will fail to get a track of your swim.

Familiarize yourself with the technology beforehand, so you’re not fumbling around during the swim itself.

Suggested Best Practice for reporting times in marathon swims

Record the date, time of day, and time zone of:

  • swim start (toes in the water)
  • swim finish (toes clear the water).

“Time of day” means:

  • hours in military format (0 through 23)
  • minutes
  • and seconds.

Reported times of day should be synchronized with official International Atomic Time.

Typically your smartphone or GPS watch should be automatically synchronized with atomic time, but many cellphones don’t display seconds by default. See if in doubt.

Elapsed time of the swim should also be noted, but should always derive from the difference between start time of day and finish time of day.

Reason: if only using elapsed time (i.e., stopwatch), what if you accidentally bump the stopwatch, or it runs out of batteries, etc.? If you didn’t record the start time of day, you have a problem.

GPS coordinate formats

When reporting coordinates of marathon swim routes and GPS tracks…

  • Degrees + Minutes + Seconds (DMS)
  • Degrees + Decimal Minutes (DDM)
  • or Decimal Degrees (DD) ?

Examples for my favorite swim spot, Promontory Point in the Hyde Park neighborhood of Chicago:

  • DMS: 41° 47’ 43.4”N, 87° 34’ 31.8”W
  • DDM: 41° 47.7236 N, 87° 34.5301 W
  • DD: 41.795393, -87.575501
  • Decimal Degrees (DD) are most practical for computer applications (e.g., - but please use at least 6 digits of precision, otherwise the stated location may not be what you think it is.

And don’t forget the negative/positive at the front. 41.795393, -87.575501 (Chicago) is much different than 41.795393, 87.575501 (northwest China) !

For live observation purposes, Degrees/Minutes/Seconds (DMS) are probably most practical, because it minimizes writing.

e.g., a given swim in Lake Michigan may take place entirely within the 41st degree North of latitude and the 87th degree West of longitude, so you can exclude the “41” and “87” for all but the first of the log entries.

DMS, DDM, and DD can all be interchangeably converted… but whatever you do, please do not mix more than one of the three formats in the same log!!!

What’s the deal with GPS watches? Can I wear one on an official Documented Swim?

In general, devices (worn by swimmer) that offer real-time direct feedback about pace or navigation are prohibited by (intentionally purist) MSF Rules.

Technically, some currently-available GPS watch models do, in fact, have the capability of real-time feedback on pace and navigation. Therefore, they are disallowed by MSF Rules. Simple analogue watches (time of day) are specifically mentioned as standard equipment.

Realistically, I doubt any marathon swimmer has gained a significant benefit – to date – from wearing a GPS watch. If anything, the bulk of current models (2017 or earlier) would contribute to performance-reducing drag on the wrist.

But why should MSF be responsible for policing specific models of GPS devices, their respective capabilities, and whether swimmers are using them to their full potential (or future potential)? Seriously, we don’t have time for that.

Sarah Thomas and Chloe McCardel did world-record swims without wearing GPS devices directly on their bodies - why do you need them? Answer: you don’t. Let your kayaker or boat pilot take care of it.

How to measure & record the wind when observing a marathon swim? Three options:

  • Handheld anemometer (Amazon link).
  • Built-in wind gauge on the escort boat. Less ideal because most captains will find it annoying if you’re asking for wind readings all the time.
  • Eyeball the conditions using the Beaufort Wind Force Scale. Once you’re familiar with the scale, it’s as simple as writing a single digit, zero through five (very rarely a six), into the observer log. If possible, the subjective Beaufort readings should be supplemented with objective weather data (e.g., NOAA).
  • Beaufort Wind Scale for Swimming

Here’s my adaptation/simplification of the official Beaufort scale description (see Wikipedia) for swim observing purposes:

  • Force 0: glassy, calm, no wind
  • Force 1: ripples on the water, a slight breeze
  • Force 2: small wind chop but no whitecaps.
  • Force 3: a few whitecaps forming
  • Force 4: moderate wind chop, frequent whitecaps, difficult for kayakers and weaker swimmers
  • Force 5: larger wind chop, difficult to swim in these conditions for long durations, unsafe for kayakers and weaker swimmers
  • Force 6: swim has probably been called off, or should be soon

What if I can’t find a trained/experienced observer or well-known fellow marathon swimmer to document my swim? Can my swim still be ratified?

Short answer: Yes, possibly, but the margin for error in the documentation is much smaller. In the absence of a known observer, the swim documentation needs to be of extremely high quality. Which means:

  • Detailed, complete, and neatly written observer log.
  • Complete GPS track, including publicly available live tracking.
  • At least one photo per hour of swimming, including the start and finish.
  • At least 60 seconds of video from the swim, showing the swimmer’s stroke.
  • Narrative report describing background, planning, and execution of the swim.
  • Signatures and contact information for all witnesses of the swim (pilot, crew, etc.).

That said, recruiting a known observer or fellow marathon swimmer or local swim official to document the swim confers a much higher level of credibility. If there is any problem with the documentation (and more often than not, there are at least a couple small problems), it can be “offset” by the personal attestation of someone who is well known to the marathon swimming community.

For sanctioned solo swims, the credibility is conferred by the local governing body itself (CSA, CS&PF, CCSF, SBCSA, NYOW, SSO, MOWSA, NOWSA, ILDSA, CLDSC, etc.) – because they provide independent observers who represent the organization. For these swims, the documentation quality is less important than the reputation of the organization.

MSF Documented Swims uses a different model of authentication. MSF does not provide independent observers - so the quality of the documentation provides the credibility. This credibility is further enhanced if the documenter is a known observer or swimmer.

Observing/documenting isn’t rocket science, but it requires attention to detail. Experienced observers are much more likely to get these details right.

Exception to above statements: Extremely high profile swims (Cuba-Florida) or record claims. In these cases, there’s really no excuse to not have an experienced/qualified/known swim observer.

Written vs. Typed Observer Logs

It’s traditional and perfectly acceptable to write observer logs by hand. Download the MSF observer forms here.

But writing on boats can be a messy business.

So, unless your log is very legible (example), it’s a good practice to transcribe/type at least the “Notes” column of the log, with timestamps, so the “story of the swim” can be easily read in a web browser.

For MSF Documented Swims, please submit both the scanned original handwritten logs, and a digital transcription of the Notes (e.g., in a Word doc). It is the observer’s responsibility to submit documentation that can be read and reviewed.

What about tow buoys like the SaferSwimmer? Can these be used on official Documented Swims?

Tow buoys are highly useful on training swims (for visibility, security of belongings, and increased self-sufficiency), but by definition are considered “Equipment that may increase buoyancy” and thus prohibited by MSF Rules on official, observed swims. We cannot think of any circumstance in which a tow buoy serves an essential function on an official solo swim, which wouldn’t be better served by a kayaker or paddleboarder.

How many photos should I submit?

One major pain point in processing/ratifying swim documentation is wading through (in some cases) hundreds of photos and video clips taken during swims.

It is great that you took lots of photos, but please do not submit “photo dumps” - i.e., every single image taken during your swim.

Please instead select a representative collection of the best photos and video footage, and include captions (in a separate text file) describing what they show.

We usually don’t use more than 20-25 photos and a couple minutes of video for MSF Documented Swims. Please don’t make us do this work for you – winnowing 500 photos down to 25. We might not pick the ones you want!

For video submissions, we’re looking for some brief footage of the swimmer’s stroke “in context.” 30 seconds from the mid-swim is fine, preferably with contextual cues to indicate the location. Start and finish are also good things to get on film.

If you have video editing skills and want to put together a longer swim-documentary, that’s great. Upload it to Vimeo or YouTube, and send us the link.

What if my observer is unable to observe the start and/or finish and/or some other part of the swim, due to obstructions that prevent the escort boat from getting close enough?

Find a way for your observer to get close enough to see it directly. If you can swim it, they should be able to observe it. You may need to plan ahead of time. Continuous observation is a non-negotiable requirement of MSF Documented Swims. Perhaps that means putting the observer in a kayak, or even having them swim with you. See the description of the last part of this swim.

Can you please ratify my swim by [insert specific date]?


How much video footage should I take?

It depends.

  • At bare minimum, we want ~30 seconds of good quality footage showing the swimmer’s stroke technique and tempo.
  • A well-documented swim should also include video of the start and finish, and a representative collection of clips from the rest of the swim, showing the variety of landscapes and conditions encountered. 5 minutes total running time is usually about right for a marathon swim of a few hours’ to a half-day duration.
  • It’s a great idea to include the date and time the video clips taken in the names of the video files you submit.
  • If you submit more than a few minutes of unedited video, it may delay when the swim is published and ratified. It takes time and effort to compile this stuff.
  • Please do not take video with your phone in “portrait mode” (tall rather than wide) unless there are visually interesting things at the top and bottom of the frame. Landscape mode (wide rather than tall) is usually the better option.

Example of good video submission - here is the video from @ssthomas’ Round-Trip Angel Island swim (which admittedly, has the advantage of being one of the more visually interesting swims in the world) -

Is my observer required to have formal qualifications or previous experience?

It depends. Because marathon swim observer training programs are limited to certain geographic areas (Los Angeles, New York, Dover), for many independently organized swims this is often not a realistic expectation.

If it’s a high-profile swim or significant record attempt, then yes, you definitely want at least one trained, experienced independent observer, preferably even two. This is necessary for the credibility of any swim for which there are relatively “high stakes.”

For most other swims, the main considerations are:

  • The person is detail oriented and capable of completing and coordinating the documentation requirements.
  • The person is capable of observing impartially and is not obviously biased, like a spouse or close relative.
  • The person understands the rules of marathon swimming. Even better - if the person is a fellow swimmer or marathon swimmer.

Your dad shouldn’t be the observer due to the appearance of or potential for bias, but you can still utilize his experience and knowledge. Suggestion: Designate the other person as the official observer, but have your dad make himself available to this person to advise and help plan the observation.