Kiwi skipper Mike Sanderson calls it "boarding school stomach".
It's the empty feeling in the pit of your gut on the first night at sea away from the comforts of home and with the tearful farewells from family and friends still fresh in the mind.
Sanderson, a veteran of three previous Volvo Ocean Race campaigns, said leaving the dock to embark on another gruelling leg was never easy. But the Auckland skipper of Chinese entry Team Sanya said yesterday's departure from his home port was the "most brutal" he'd experienced.
Not just because he is anxious about the treacherous conditions the fleet will encounter on the 6705-nautical-mile slog to the Brazilian city of Itajai, but because this is the first time he's sailed into the Southern Ocean since becoming a dad to 4-year-old Amelia and 2-year-old Merrick.
"This one has been hard for lots of reasons - this is the first time I'm going into this leg with two little kids running and jumping on the bed. That makes a big difference, I'm not going to lie," said Sanderson, who won the 2005/06 race with ABN Amro.