Is Lewis Pugh physically ready to take on The Long Swim?

Ocean campaigner Lewis Pugh has passed a series of physical tests to confirm he is ready for an epic 350-mile swim along the length of the English Channel.

Sky News took the endurance swimmer to a sports physiology laboratory at the University of Portsmouth, where scientists monitored his response to cold water – and calculated how many calories he will burn.

“This will be my toughest swim,” Lewis told us.

“No one has done this distance to Channel Swimming Association rules – cap, goggles, Speedo costume and nothing else.”

Lewis has done months of preparation in the sea off Cape Town, where he lives.

But this was the first time that he has trained while scientists monitored his heart with ECGs and his core body temperature with a rectal thermometer.

They first tested his response to cold water, plunging him into a pool set at 18C, the same temperature as the Channel.

Cold water shock can cause a cardiac arrest. But Lewis has swum in the Arctic and Antarctic, so it was no surprise that his heart rate remained unchanged.

“That’s the classic response of someone who is cold water habituated,” said Professor Mike Tipton, the university’s director of sport science research.

“Normally what we would see is gasping, hyper ventilation and an increased heart rate. Cold water shock is responsible for 60% of open water deaths.”

Lewis also passed a hypothermia test in a flume, the swimming equivalent of a treadmill. Despite the cold water his body temperature rose by 0.4C.

He has put on several kilograms of fat to retain the heat generated by exercise.

“Lewis has the classic body shape of a Channel swimmer,” said Prof Tipton.

“He won’t have a thermal problem as long as he keeps his pace up. But his peripheral tissues will have cooled in the water so he will get colder when he gets out.

“The critical aspect is warming him up quickly, and making sure he replaces the energy he has lost, so he is prepared for the next swim.”

Analysis of Lewis’s exhaled breath showed he burns 900 calories an hour while swimming – or as much as 10,000 calories a day.

He will eat boiled eggs and peaches to keep his energy up while swimming in the Channel. But he is certain to vomit several times because of the exertion and the large amounts of salt water he will swallow.

Lewis said: “What they can’t capture here is when you are fighting against the tide and suddenly you are swimming through a bloom of jellyfish, or the support boat has a problem.

“Layer after layer of problems keep arising. This is a laboratory. When you get out into the sea it is very different.”

One person who has an inkling of what Lewis is up against is Victoria Cox. She swam across the Channel last summer.

“What he is doing is in a totally different league,” she said.

“The amount of mental fortitude required to believe in himself and do it day after day is incredible.

“He will be mentally and physically exhausted.”

(c) Sky News 2018: Is Lewis Pugh physically ready to take on The Long Swim?