With the 35th America’s Cup in full swing, the performance team at Oracle Team USA is under pressure to ensure their sailors are at the top of their game.

And when it comes to health, what’s happening “under the bonnet” matters just as much as their external fitness, according to physical performance manager Craig “Oscar” McFarlane.

Mr McFarlane and Scott Tindal, the team’s head physiotherapist and nutritionist, gave some insight into what it takes to keep the sailors at peak health during the launch party for Ixcela, a new Massachusetts-based internal fitness company focusing on gut health and wellness that was cofounded by doctors Erika Angle and Wayne Matson.

“We get so much pressure from the people who select the crew, Tom [Slingsby] and Jimmy Spithill, we need these guys to sail, it’s as simple as that,” Mr McFarlane said.

“The training is quite easy because they want to train, obviously it’s their job, but managing their health is quite hard because you’re redlining all the time. You’re trying to push them, get them comfortable in an uncomfortable environment.”

But pushing them to their limits increases the risk of illness because of the pressure placed on the immune system by the intense training, he explained.

“Apart from preparing these guys for this amazing event, I’ve got to make sure I give to Tom and Jimmy, who select our crew, 14 healthy specimens who can sail in any one day. Their availability at this time of the Cup is absolutely crucial.”

Noting that sickness is unavoidable at times but avoidable at others, he said it was important to look at their internal health and fitness, as well as what is happening externally, and Mr Tindal added the gut microbiome — the collection of microbes or microorganisms that inhabit in the gut — “is part of the puzzle with health”.

The team partnered with Ixcela, which has developed a test to help individuals measure and improve their internal fitness, about a year ago. The sailors took the blood test and as a result of the changes implemented based on the results. Mr Tindal said they had seen “dramatic” changes in the sailors’ availability.

“Availability is really the ability for the sailors to fully train or be available for selection for sailing and that’s one of the biggest things we look at,” Mr Tindal said, adding that the team had been having problems with upper respiratory tract infections, which led to a total of 61 days off.

“We went from 61 days lost to over the next six-month period having 14 days lost. That’s an incredibly powerful statistic to us.”

According to Dr Angle, a biochemist with degrees from MIT and Boston University School of Medicine, there is a “definite connection” between poor gut health in youth and significantly increased chances of developing neurodegenerative diseases, cancers, diabetes or other autoimmune conditions later in life.

With years of research showing the importance of physical fitness, she said “the reality is that what you do inside and the fitness inside your body is equally important if not even more so than the external fitness”.

“We damage our microbiome based on the types of foods we eat, products that we are exposed to — many of the plastics, chemicals that we are exposed to.

“Many of the species that live in the intestine, they spit out or secrete out into the blood different compounds, many of which are actually protective.

“So if you go and wipe out your species, you simply don’t have all of the building blocks that are necessary to then go and protect you against some of these diseases.”

The pinprick blood test developed by her company looks at 12 compounds that have been linked to diseases such as Alzheimer’s disease or coronary heart disease. “Interestingly enough, they are all compounds that are secreted by bacteria in your gut,” Dr Angle said. “Hence we became an internal fitness or gut microbiome company.”

While the company has worked exclusively with Oracle Team USA for the America’s Cup, she said the test had a general target audience, from health conscious younger people, to those with a family history of illness.

“We could not be more thrilled to bring this product to market, and make the same benefits that Oracle Team USA has realised available to the public,” she added.

Ixcela also has a presence at the America’s Cup Event Village along with Dr Angle’s not-for-profit Science from Scientists, which focuses on Stem education and is an educational partner with the America’s Cup Endeavour Education Station presented by Orbis.