Space-age science
Chasing discoveries as close as the heart, as far away as the moon
Dr. Benjamin Levine’s career reads like an adventure novel. Known around the world among sports cardiologists – consultant to the NCAA, the NFL, and the U.S. Olympic Committee & Paralympic Committee – he also works with NASA to solve medical problems related to spaceflight.
His first research paper, on the success of a drug to treat altitude sickness in mountain climbers, made it into the New England Journal of Medicine while he was still a cardiology fellow. More recently, a 2018 study showing strenuous exercise can reverse the heart stiffening and shrinkage associated with aging created a media frenzy.
But Dr. Levine’s career in medicine almost didn’t happen. The UT Southwestern Professor of Internal Medicine started as a music major at Brown University, thinking he would play classical saxophone. Just in time, the doctor’s son from Long Island realized orchestras don’t need many mediocre saxophonists, so he switched to human biology: “It was probably the simplest way for me to graduate on time,” he says.
That led him to Harvard Medical School. “I said, ‘I’m not going to be a musician. What else do I really like to do?’” Dr. Levine recalls. He had always been athletic, playing on Brown’s tennis team, serving as captain of its wrestling team, even doing a little mountain climbing.
“I loved sports and athletic competition and the limits of human performance,” he says. “I said, ‘Well, maybe I can be a sports medicine doctor.’”
Training under giants
After medical school, Dr. Levine headed to California for an internal medicine internship and residency at Stanford University, where he found himself training under some of the country’s foremost experts in alpine medicine. In the emergency room, there was Dr. Gil Roberts, a member of the first successful American expedition to Mount Everest in 1963. Another was Dr. Herb Hultgren, former Chief of Cardiology at Stanford University Medical Center and an avid climber and researcher who later wrote the book High Altitude Medicine. Then while eating in the Stanford cafeteria one day, he met Dr. David Shlim, who worked with Dr. Peter Hackett, the Stanford emergency room physician who helped found and became Medical Director of the Himalayan Rescue Association in Nepal.
Under such influences, Dr. Levine stepped up his mountain climbing. He has summited Denali (formerly Mount McKinley) in Alaska as well as Mount Lobuche in Nepal, and climbed on Mount Everest. In 1985, as he approached the end of his residency, Stanford offered him the job of Chief Resident, but he declined: “I said I’d rather go to Nepal.”
A yearlong scholarship from the Henry Luce Foundation took him as far as Japan, where he studied altitude sickness in the Japanese Alps. From there, he headed to Dr. Hackett’s Himalayan Rescue Association, where he treated patients with acute altitude sickness. The New England Journal of Medicine paper on the drug dexamethasone as a treatment followed in 1989, with Dr. Levine as first author.
By then, he knew he wanted to be a researcher as well as a cardiologist. “Where could I go in the United States to get great clinical training in cardiology and great research training in cardiovascular/exercise physiology?” he had asked his Stanford mentor, Dr. William Haskell, an American College of Sports Medicine President.
“I would give my right arm to work with Jere Mitchell and Gunnar Blomqvist,” came Dr. Haskell’s response. Both respected UT Southwestern cardiologists, Dr. Blomqvist (now deceased) and Dr. Mitchell were researchers on the 1966 Dallas Bed Rest and Training Study, a landmark report published in Circulation two years later that showed 20 days of bed rest dramatically reduced the fitness of young men.
Dr. Mitchell, Professor of Internal Medicine and Physiology, remembers recruiting the young Dr. Levine to UT Southwestern in 1987. “He seemed so committed to a career in research,” Dr. Mitchell recalls.
Launching space/health research
At UT Southwestern, Dr. Levine began the research for which he is well known: the connection between exercise and heart health, and the effects of space travel on the human body.
Dr. Levine was 13 years old in 1969 when Neil Armstrong stepped onto the moon. Two decades later, as a cardiology fellow at UT Southwestern, he implanted the first catheter to monitor heart pressure in an astronaut in space. The test participant was Dr. Drew Gaffney, a UT Southwestern cardiologist who had trained to become a NASA astronaut.
In 1989, as UT Southwestern prepared to conduct its space experiment with Dr. Gaffney, Dr. Levine applied to NASA to become an astronaut himself. “They ended up disqualifying me because of my color vision – actually, the lack thereof,” he says.
“That turned out to be a good thing,” Dr. Levine says now. “Most of what the astronauts did was fly around the Earth a few times doing other people’s experiments. Being rejected gave me the opportunity to define the problems and ask key questions.”
Instead of flying, Dr. Levine has led NASA-funded research into such questions as why astronauts develop vision problems and why they are prone to fainting after they return to Earth. The answers: In the first case, persistent, mildly elevated pressure inside the skull during spaceflight changes the shape of the eyeball. In the second, cardiovascular deconditioning combines with circulatory system changes in the low-gravity environment to affect blood flow.
Last year, Dr. Levine successfully demonstrated a strategy to reduce the fainting – having astronauts exercise regularly while in space to prevent deconditioning, combined with saline infusions upon their return to Earth to boost blood pressure. Dr. Levine’s space findings help the Earth-bound patients he treats who faint due to a condition called postural orthostatic tachycardia syndrome (POTS) in which too little blood is sent to the heart after a reclining patient stands up.
Dr. Levine has also continued to study the effects of deconditioning due to a lack of exercise on the ground. His collaborations with Drs. Blomqvist and Mitchell led to important findings as they followed up on the 1966 Bed Rest Study.
Bed Rest study redux
In 1996, three decades after the original study, Dr. Levine and other researchers brought the five participants – now well into middle age – back to UT Southwestern. What they found astounded them. Thirty years of aging had done less to reduce the men’s conditioning, or cardiovascular capacity, than had 20 days of bed rest when they were 20 years old. “We found that not a single person was in worse shape after 30 years of aging than after three weeks of bed rest,” he says.
That study led Dr. Levine to a chain of research projects over the next two decades to see if exercise could prevent the effects of aging on the heart – and if it might even reverse them.
“In my career, one of the things that surprised me the most is that the heart stiffened and atrophied after bed rest,” Dr. Levine says now. “That was an ‘aha moment.’ That finding led me to question how much of what we assume to be an inevitable consequence of aging is really due to deconditioning.”
In a 2004 study, Dr. Levine reported that Masters athletes in their 60s – people who exercise regularly and strenuously – had hearts indistinguishable from those of sedentary control participants in their 30s in terms of the stiffness and pumping ability of the left ventricle, the chamber that pumps blood throughout the body.
Next, the researchers investigated whether a year of vigorous exercise could turn back the clock in sedentary individuals. Examining sedentary test participants in their 70s, Dr. Levine found that while exercise had some heart benefits, it wasn’t enough to reverse heart stiffening.
In 2018, Dr. Levine and his researchers finally hit pay dirt. This time, they recruited test participants ages 45 to 64 for a two-year study involving regular exercise. In this group, the regimen managed to decrease heart stiffness and improve maximal oxygen intake, a measure of cardiovascular fitness, Dr. Levine’s team reported in Circulation.
There have been additional highlights.
Dr. Levine says he’s best known for a study on altitude training for competitive runners, known as “Living High-Training Low” and published in 1997 in the Journal of Applied Physiology.
Notable achievements
He regards the Institute for Exercise and Environmental Medicine, which he founded in 1992 and now directs, as “probably my greatest achievement.” A joint project of Texas Health Presbyterian Hospital Dallas and UT Southwestern, the Institute has grown into the largest center for the study of human physiology in the United States, he says. “People come from all over the world to train and study.”
This year, Dr. Levine received the American College of Cardiology’s Distinguished Scientist Award (Translational Domain).
“It’s really hard for me to pick just one achievement,” he says. “And maybe that’s part of the fun aspect of my career, right – that it’s not just one thing.”
His quick and curious mind has leapt from one challenge to the next – and he says UT Southwestern has let him do that. “I’ve been very fortunate. No regrets.”
Well, maybe just one. In 1954, his father, a doctor then serving in the Army, was on his way to Fort Sam Houston in San Antonio with his wife when he got word to head to the Military Academy at West Point instead. Dr. Levine was born there two years later.
“I could have been a native Texan,” the New Yorker says with a sly grin.
Dr. Levine holds the Distinguished Professorship in Exercise Sciences.
Dr. Mitchell holds the S. Roger and Carolyn P. Horchow Chair in Cardiac Research, in Honor of Jere H. Mitchell, M.D.