Lewis Pugh has followed an unspoken rule during his career as one of the world’s most daring endurance swimmers: Don’t talk about sharks. But he plans to break that this week on a swim around Martha’s ...

For his swim around Martha’s Vineyard in 47-degree (8-degree Celsius) water he will wear just trunks, a cap and goggles. Pugh, 55, is undertaking the challenge because he wants to change public ...