When a person accidentally falls into frigid water, the first minute after entry is the most critical in the struggle to survive.

Dr. Michael Jacobs, one of the Island’s highly regarded sailing doctors, gave a talk on Tuesday evening about ways to survive after an accidental plunge. His message to boaters is that most people aren’t aware where the dangers really lie that lead up to death in the water.

The lecture was given to 23 members of the Sail Martha’s Vineyard rowing club at the nonprofit’s headquarters on Main street in Vineyard Haven. He provided two videos and shared the conclusions of years of research. The rowers are an active group of enthusiasts. Many of them row year-round, going out every morning in a 32-foot pilot gig for exercise, fellowship and fun.

The key ingredient to staying alive is being able to keep breathing and control that breathing. The first moment in cold water is the most dangerous. “The initial response, which affects breathing, heart function, and muscle strength, is called cold-shock response. This is a series of reflexes that begin immediately upon sudden cooling of the skin,” he said. It is not controllable.

Mr. Jacobs’s one hour presentation kept leading back to one critical fact; life jackets or personal flotation devices (PFD’s) will save a person’s life.

There is a formula for anyone struggling to stay alive in cold water. “It is called 1 - 10 - 1. You have one minute to control your breathing, ten minutes to do something to get yourself out of the water or safe.

Mr. Jacobs said cold water can be water less than 60 degrees, often the water temperature in this region. However, he said: “Water temperature as high as 68 to 77 degrees can kill you just as easily. Fall into cold water without a PFD and you could drown in the span of a few minutes, often within 10 feet of safety.”

Dr. Jacobs explained that after one is able to control their breathing, a person in the water has about ten minutes to get themselves out of trouble, before they lose their ability to use their arms and legs. It may be swimming, it may be pulling oneself out of the water onto a boat. Whatever one does, they have ten minutes or less to take an action.

A good deal of the beginning of the doctor’s program was devoted to trying to explain that a person drowning is not someone waving their hands frantically in the air, calling loudly for help. The drowning victim is often far more subtle, far more passive. Mr. Jacobs said parents can benefit from learning to be more aware of their children’s behavior in the water. Some drowning accidents involving children have occurred when a parent was nearby and they didn’t see clearly that their child was distressed and not able to call for help.

Mr. Jacobs said that when a person has inhaled water and is gasping for air, their goal is trying to stay alive; they have no energy to call for help or thrash the water.

In a video called Cold Water Boot Camp, Mr. Jacobs presented the results of four people jumping into cold water. The movie demonstrated how clearly the swimmers became disabled and helpless within minutes. It also included interviews with the volunteers about what they experienced as they struggled to stay above the water and make it ashore. The video is viewable on YouTube.

The doctor’s lecture was one of two presentations given to the rowers at Sail Martha’s Vineyard. On Wednesday night, the club heard from Sean Bercow, the captain of the sailing ship Amistad. He gave a talk on how best to communicate on the water. The talk was geared for coxswains, those who lead the rowers in the boat.

Afterwards Brock Callen, of Sail Martha’s Vineyard, said the organization regularly gives programs to help boaters improve their skills. He complimented Dr. Jacobs for the help he has offered sailors in the past about medical issues on the water. He said this winter the nonprofit organization is offering a coxswain course to bring new leaders into the rowing club and also recertify those who are already experienced.