The images on the screen at NASA’s Johnson Space Center began as sounds, transmitted via sonar from an echocardiogram machine measuring the heartbeat of Ben Lecomte, who is currently swimming 5,500 miles across the Pacific Ocean from Tokyo to San Francisco, with the goal of becoming the first person to freestyle swim across the Pacific.

The images, recorded by Lecomte and guided by a NASA sonographer, will tell Benjamin D. Levine, MD, FACC, and his team at the Institute of Exercise and Environmental Medicine (IEEM) at Texas Health Resources in Dallas, how Lecomte’s heart performs while he swims for eight hours every day for about five months. They will provide insight into how sustained high-intensity exercise affects cardiovascular health.

Levine, who is also professor of medicine and distinguished professor of exercise sciences at UT Southwestern, began mapping what he calls “the outer edges of human performance” at the IEEM, which he founded with Jim Knochel, MD, and Doug Hawthorne in 1992. The center was the ideal place for Levine to explore his fascination with exercise, endurance, space and altitude. “I’ve always been intrigued by the limits to human performance, whether for an astronaut or a climber,” explains Levine, who was a collegiate competitive wrestler and tennis player. He was intrigued by research that shows that endurance athletes live longer than the general population. “As a physician, what interests me most is what we can learn from these extraordinary individuals about patients and their endurance. Indeed, what limits a climber on the summit of Mt. Everest is remarkably similar to what limits patients with heart disease (such as heart failure) from being able to accomplish their activities of daily living."

Levine spent his early career studying the effects of altitude and exercise on the heart – even working on rescues in the Himalayas. While he was in Japan on a Henry Luce Foundation scholarship in 1986, the Challenger disaster happened, which slowed down a lot of work in spaceflight research. Levine returned to the U.S. to do his cardiology fellowship at UT Southwestern where he began to study orthostatic intolerance, a condition that often affects pilots, causing them to feel faint upon standing. “Pilots were encouraged not to do a lot of endurance training,” said Levine. “Why can’t athletes be good pilots?” To find out, he studied athletes and astronauts. “We did preliminary studies and it looked like it was the enlarged hearts of athletes that increased the risk of fainting.”

Since then Levine has worked with NASA on several projects, including Space Lab Missions, and as a consultant to the National Collegiate Athletic Association, National Football League, National Hockey League, the U.S. Olympic Committee and USA Track & Field. He is also an active member of ACC’s Sports and Exercise Cardiology Section.

It was Kenneth H. Cooper, MD, MPH, another physician with a lifelong interest in fitness, who approached Levine about working with Lecomte. Cooper had been working with Lecomte to devise a waterproof Holter monitor, and contacted Levine after reading a paper Levine and his colleagues had published about Charlie Engel, one of the world’s foremost ultra-long distance runners. Before and during Engel’s attempt to set the speed record for running across the U.S. (3,000 miles in 45 days), Levine and his colleagues performed echocardiography and biomarker analyses on him. “[Cooper] called me and asked if I would like to be involved in the swim across the Pacific. I met with Lecomte and he was very enthusiastic about going through many of the same procedures we did with Engel,” he explains.

Levine doesn’t anticipate that NASA’s remote guidance echocardiogram – the same method he uses to monitor astronauts’ hearts on the International Space Station – will show any evidence of cardiac injury, given Lecomte’s overall excellent health and low intensity of the swim. But in this cardiologist’s hands, the results of Lecomte’s monthly oceanic echocardiogram – which will be completed next spring – will become part of a new map to the thresholds of health, aging and physical fitness.

Keywords: Cardiology Magazine, ACC Publications, Sports