Victim Recognition: Medical Events & Shallow Water Blackout

It’s important that we bring a sense of urgency to the issue of recognizing adult drowning, and increase awareness around why these incidents continue to happen. Extended breath holding and medical events are two leading causes of aquatic injuries among adults. We have designed this guide to help you identify the signs of both, and to understand important methods for prevention and quick response time.

Please review the information below with the lifeguards and staff at your organization.

Extending Breath Holding

Extending breath holding is a common practice among aquatic athletes, as well as naval, marine, and coast guard trainees. It is a dangerous practice that many pools have banned. Because of extended breath holding, even the most experienced, able-bodied swimmers can become prone to drowning, as the body could easily become deprived of oxygen before it sends a warning signal to the brain, causing the victim to succumb to shallow water blackout before they ever get the urge to breathe. Here are signs to look for so that intervention is possible:

  • Using a stop watch to measure time spent underwater.
  • Hyperventilating, (repeated deep breaths) to prepare for an extended time underwater.
  • Swimming long distances under water, or swimming without regular breathing between strokes.
  • Breath holding competitions.
  • The use of weights or a weight belt to keep the swimmer on the bottom of the pool.

Medical Events

Lifelong swimmers and older members may drown because of a medical event like a heart attack, stroke or seizure. Preexisting conditions and medical emergencies can easily become exacerbated in the water, and damage cause by drowning could result in long-term issues such as learning disabilities, memory loss and permanent physical impairment. These are signs guards can look for to help shorten response times:

  • Irregular, uncoordinated movements. Movement is not necessarily a sign that someone is okay/conscious.
  • Sudden behavior changes (such as difference in swimming stroke)
  • Stopping in the middle of the pool.
  • Floating/sub-surfaced with little to no movement.
  • Clutching one’s chest or arm.
  • Confusion and/or loss of speech, coordination or responsiveness
  • Trouble swallowing, nausea, vomiting, hiccups, dizziness
  • Chest, arm, jaw, back or general upper body pain that may or may not be temporary

Note: The Center for Disease Control found that drowning is the leading cause of unintentional death for people with seizure disorders. The CDC recommends that patrons with a history of seizures receive one-on-one supervision in the water.

Layers of Protection for Adult Swimmers

Leadership has a responsibility to set expectations, promote lifeguard vigilance, and ensure that all aquatic rules are enforced consistently. Here are some ways that leadership and guards can work together to protect adult swimmers:


  • Empower guards to interrupt any concerning or prohibited behaviors, such as extended breath holding—no matter who is practicing them.
  • Energize your guards by having them participate in quick, fun, team building hand-eye coordination games before their shift. They may be coming from another job, or a long day at school and can benefit significantly from interactive encouragement and support.
  • Increase guard rotations during the down times at your pool. Talk with guards to determine how you can best support them during slower, more monotonous times.
  • Implement Drop Drills on a regular basis to improve response and rescue times. Review our DROP Drill Implementation Guide.
  • Review the signs of medical events and extended breath holding regularly with your staff, so they know what to look for.


  • Adequately assess adult swimmers while scanning the pool. Be aware of the warning signs shared above.
  • Educate members on what behaviors will result in lifeguard intervention, and why.
  • Remind members/guardians of their responsibility to report any special needs or medical conditions at the onset of their membership, and before entering the pool.

Our movements have done incredible work in driving down the rate of children drowning in our pools. Now we need to do the same for the adults in our community too. We appreciate your attention to this urgent matter—please don’t hesitate to reach out if there is any way that we can help.