USRowing’s 2007 Safety Video provides an excellent summary of the dangers of cold water rowing. Following is a partial transcript from that video.*
“Being in water below 80 degrees is potentially dangerous; it is extremely dangerous when below 50 degrees.
“Cold water immersion follows four stages: starting with cold shock, followed by swimming failure, then hypothermia, and finally post rescue collapse.
“It is believed that the majority of deaths happen during the first two stages.
“The initial cold shock from falling into cold water provokes an immediate gasp reflex of up to two to three quarts of air, or water if your head is submerged.
“During this period concentrate on staying afloat with your head out of water and once your breathing is more normal and your heart rate is reduced you will think more clearly and make better decisions.
“Next, swimming failure sets in after three to thirty minutes of immersion.
“Tests using Olympic swimmers showed how the body progressively becomes more vertical in the water due to loss of muscular coordination. This is why staying with the boat is critical. Physical exercise such as swimming causes the body to lose heat at a much faster rate than remaining still in the water, because blood is pumped to the extremities and is quickly cooled.
“Immersion in cold water can quickly numb the extremities to the point of uselessness; within minutes, severe pain clouds rational thought. Hypothermia can set in after five minutes in the water, depending on water temperature, body type size insulation of clothing, acclimatization, and level of exhaustion and other factors.”
In the case of capsizing, the Safety Video advises “If the coaching launch is nearby, everyone should be thrown a lifejacket and put it on. In the rare case that the coaching launch is then swamped and rescue is not imminent… it can be a very short time before judgment become clouded by cold.”
* In the video this transcript begins just before the twenty-one minute mark. It has been reformatted for clarity and emphasis but otherwise unedited.