They will be swimming in a potentially lethal water temperature of around 4°C.
Although the route is 82km, they expect to swim about 110km due to currents and anticipate taking about 48 hours to complete the challenge, set down for 1 August. In addition to being exposed to the harshest possible elements as well as hypothermia, they will be sharing the ocean with walruses and killer whales.
Barkai, chairman of the International Ice Swimming Association, said the challenge promised to be "an epic adventure and a true test of physical and mental endurance."
"We plan to swim 15-20 minutes per interval to allow for recovery before getting back in about 10 hours later and repeating this until we complete the challenge. Exposing the body to such temperatures takes a serious toll and we expect some swimmers to pull out, putting further pressure on the team."
The Bering Strait (known as the "ice curtain") between Russia and Alaska is extremely remote and covered with thick ice most of the year. It defrosts during the Northern Hemisphere summer, allowing for the swim challenge.
Barkai said apart from the physical test, the logistical, political and bureaucratic challenges involving both the US and Russia were immense: "To date, every expedition to walk, boat or kayak across the Bering Strait has met failure and/or arrest. We hope we are successful."
