To paint a picture — the first word that comes to mind when I try to describe Carl Foster is affable.
I immediately question myself: isn’t that language a little elevated? A little highfalutin? But upon reflection, the word fits. Foster’s demeanor combines an easygoing, workaday approachableness with the palpable backpressure of decades of academic experience. “Friendly” doesn’t quite cut the mustard, but “perspicacious” is over the top, and leaves out how approachable he indeed is.
So, we put just a little extra spin on the ball and go with affable after all.
The 2024 ACSM Honor Award recipient, an ACSM fellow since 1981, is professor emeritus in the University of Wisconsin-La Crosse’s Department of Exercise and Sports Science, where he spent the majority of his lengthy career.
An education, a realization
But Foster didn’t expect to become a sports medicine researcher.
“I’d started out to be a physician,” he says. “I also started out to run the mile in under four minutes. I realized that by my junior year of college, I had abysmally failed at both of the major goals of my early adult life.”
Said swan song-ish junior year took place at Abilene Christian College in Abilene, Texas, where he was completing a B.S. in zoology (’70). Not quite knowing what he was going to do with his life, Foster found himself visiting the University of Texas to watch the Texas Relays. While there, he stopped by the student union and happened across an exhibit by ACSM Fellow Jack Daniels detailing a study about runners.
“I had gone to a church school and did not know that Jack Daniels was a whiskey,” Foster quips. “I just thought it was a man’s name. But, his research seemed very appealing, and again, with a degree in zoology, what are you gonna do? I wasn’t gonna go to medical school, I knew that. Because I didn’t have the grades for it.”
Foster decided then and there that exercise science was the ticket to his future. He signed on at Texas, eventually earning an M.Ed. (’72) and then a Ph.D. (’76) in physical education.
“It turned out that Jack and I got along really well,” Foster says. “Our styles are fairly complimentary, and he was studying runners and I was a failed runner, with a terminal sense of curiosity.”
Later he says, “In the process, I found out I like doing research, and I went and did a postdoc and then got into a university hospital job.”
The postdoc was at Ball State University in Muncie, Indiana. The job was at the University of Wisconsin Medical School’s Department of Medicine.
“A lot of the steps along the way were purely serendipitous,” Foster says. “Which means I wasn’t planning on something happening a certain way, but when it did I was just smart enough to realize it and run with it.”
Keep that word, “serendipitous,” in mind.
For his postdoctoral work, Foster focused on muscle metabolism and diabetes with David Costill, who served as ACSM president from 1976 to 1977. It gave Foster the opportunity to rub shoulders with a wider range of research subjects.
“I was still always interested in sort of being a physician,” he says. “That’s the way my brain is bent. So I liked working with sick people and, you know, I still enjoyed athletes, but it’s nice to work with normal people.”
Stepping into a career
While at Ball State, Foster met ACSM leading light Michael Pollock (ACSM president from 1982-3), who was starting a cardiac rehabilitation program in Milwaukee. Pollock offered Foster a job, leading to a decade of fruitful work at UW’s medical school. (Foster would go on to present the 2001 Michael L. Pollock Memorial Lecture for ACSM.) When Pollock moved on, Neil Oldridge, ACSM president from 1990 to 1991, came in as his boss. When he too moved on, Foster took over as the head of clinical physiology.
However, after about another 10 years in this role, the group of physicians Foster worked with decided to move into private practice. Being a Ph.D., he knew he wouldn’t be much use outside of a university setting. So after a bit of a scramble, he landed a job at UW-La Crosse, where he would spend the rest of his career.
Foster’s research interests are broad. One wouldn’t call him a generalist exactly, but he’s been willing to follow his curiosity into a relatively wide range of exercise science topics. Which is to say, he may have spent his career in Wisconsin, but he certainly hasn’t been siloed. He’s studied runners extensively — no surprise, given his personal interest in the subject — but is also well known for his work with U.S. Speedskating. Left-ventricular function, too, has been a major focus. Reading through the grants he’s received, a hefty proportion center on cardiac performance, but one also encounters research related to the effects of oxygenated water on cycling performance, evaluations of heart rate monitors, and exploration into interval vs. continuous training on insulin sensitivity. The CV he shared with me lists 570 publications to date.
Three exemplary lines of research
Overtraining
I ask him about his favorite findings.
“It’s funny,” he says. “It’s in a tiny little journal. It’s a single paper in the South African Journal of Sports Science.”
The focus was on overtraining.
“Thanks to a response from a coach to a smart-mouthed athlete, we had done a little study on comparing what athletes thought they were doing and what coaches thought they were doing,” Foster says.
The study design involved surveying both the athletes and the coaches, and the results were telling. As Foster puts it:
“When you asked (the athletes) to rate the last several workouts they’d done, on the days the coach thought were going to be easy the athlete always thought it was harder than the coach intended. And on the days the coach wanted to be hard … the athletes were training less hard than the coach wanted. And so there’s this fundamental discontinuity between coaches, intentions and athletes.
“This was, to me, fantastic because it explained overtraining syndrome in a second. Almost all the problems we have are that athletes are so motivated that they’re dumb. The coach says ‘You need a day off today’ and the athlete says ‘Well, I just won’t run intervals in front of my coach.’ Well, the next day when the coach wants them to run hard, the athlete’s too tired.
“And so to me, that was one of those ah ha! moments where you explain something you didn’t intend to explain.”
Sudden Exertion
According to Foster, two more lines of inquiry stand out from the rest of his career.
The first came about while he and his team were studying left-ventricular function. Most of their subjects were cardiac patients; therefore, they needed to establish a set of healthy controls. And so they’d sat a rugby player on a stationary bike and begun imaging his heart. A passing cardiologist happened to pop his head in the door and said, essentially, “What happens if he just goes for it?”
They laughed it off, but the question stuck in Foster’s mind. Shortly after the testing concluded, Foster went to his office and dug out a reprint of a UCLA paper focused on sudden strenuous exercise. The article reported some strange results.
Intrigued, he got ahold of the rugby player again.
“We brought him in, but we turned the bike up all the way up to the top, and then we said ‘Go.’ So he was just cycling as hard as he could, and we got abnormal findings,” Foster says. “That led to a whole series of studies. So it was sort of a joke and getting a reprint that day, not an hour later, that led to a series of studies that explained a lot for us.”
Ventilatory threshold
The third standout line of inquiry took place while he was supervising a La Crosse student’s master’s thesis. She was studying the Talk Test (to put it simply: “How well can you talk while you’re exercising this hard?” “What about now?” etc.). As the study progressed, Foster’s gears started to turn.
“I thought, well, it might relate to what’s called the ventilatory threshold — the thing that happens when you speak is that you have to suppress your breathing.”
Here, the professor emeritus shows himself. Foster instinctively makes the concept both concrete and local:
“Sitting there listening to me, you’re breathing 12 times a minute,” he says. “Me speaking to you, I’m breathing seven or eight times a minute because I’m suppressing my breathing frequency.”
He continues: “Well, that’s easy to do at rest. But when you’re exercising, and your body wants to breathe 20 times a minute, suppressing your breathing frequency is really hard. And you perceive that as not being able to talk comfortably.”
Foster subsequently supervised more than 20 master’s theses related to the Talk Test vis-à-vis ventilatory threshold.
We take a small detour into how this might relate to sea shanties and soldiers’ marching songs. It would appear that over the millennia, humans have run a sort of natural experiment about the benefits of exertion performed at a talking pace. (Foster: “We’ve probably known this viscerally for a 1,000 years.”)
But what’s the science behind it?
“By suppressing your breathing frequency, what’s happening is you’re retaining carbon dioxide,” Foster says. “If you’re retaining carbon dioxide, your brain knows about it in a hurry.” Then: “About the point where you go from ‘Yes, I can talk comfortably’ to ‘Yes, but —’ is about the first ventilatory threshold. Which is about the first time you start accumulating lactic acid.”
After which comes the second ventilatory threshold:
“At just about the point where you probably do become acidic is when the second ventilatory threshold happens and you say ‘No, I can’t talk.’ You’re talking in one word or two words, or something in that order.”
The takeaways are significant. If you’re looking to encourage a sedentary person to exercise, tell them to do so only to the point where they can still talk. If you’re working with athletes who want to incrementally push their envelope, ask them to train within that zone where talking is difficult but still possible. Further, an attentive coach can simply listen to his athletes while they run by: if they’re chatting, they’re below the first ventilatory threshold. It’s an eminently applicable rule of thumb.
“One of the themes, that I shared with John Porcari, FACSM, particularly of the last 20 years of my career,” Foster says, “is, ‘Can we find a simpler way to do what we’ve been doing in a complicated way?’”
That the Talk Test maps predictably onto the two ventilatory thresholds is certainly elegant in its simplicity. This kind of down-to-earth, applicable science is irresistibly appealing. Hazarding a guess, I’d say it’s because it is so very human.
On ethics
Something else Foster shares dovetails into that sentiment:
“Most studies I’ve done, I’ve been subject No. 1,” he says.
I suggest that’s a wonderful thing for a researcher to do — that it is, indeed, very human to make sure you’re the first to experience what you’re asking others to endure.
He counters: “I was not being particularly noble about it. I wanted to design better experiments. And I sort of figured out the best way was, ‘What do I expect the patient to feel? Do I feel that myself?’”
But despite the deflection, it seems pretty clear his motivations are more altruistic than he’s letting on. A short while later he says “The rule for the last 20 years in my lab is, you don't do anything you haven’t had done to yourself — and aren’t willing to have done again.”
He elaborates, citing gastric-emptying studies as a particularly onerous example: a tube down the nose sucking the remaining fluid out of one’s stomach after an experiment. Here, the young undergraduate who wanted to become a doctor flashes briefly before me: Do no harm.
On receiving the 2024 ACSM Honor Award
We turn to his being the recipient of the 2024 ACSM Honor Award. More humility:
“There are people like Mike Joyner who got it last year who can get it totally on the basis of their work,” Foster says. “Mike is a great scientist — I mean, beyond great. There are other people, like myself, who have done a lot of work for ACSM.
“I’ve had a good scientific career, and I’m proud of it, but I also did a lot of work for ACSM.”
Foster’s service to the college has indeed been extensive. As noted above, he joined the organization in 1974, putting him at a half-century of ACSM membership, and was an ASCM fellow by 1981. He has served variously as ACSM president (2005-6), treasurer (2014-20), vice president of basic and applied sciences (1985-7), a three-time member of the ACSM Board of Trustees (1983-7, 2003-7, 2014-20) and likewise the Program Committee (1985-7, 2003-7, 2009-14; he also served as chair from 2004 to 2005), associate editor of Medicine & Science in Sports & Exercise® (MSSE) for 16 years, and MSSE associate editor-in-chief (2000-4).
To list all of his contributions would push this article dangerously far beyond its metabolic threshold. Instead, what about his future plans?
What’s next
Foster holds up a yellow legal pad with his to-do list jotted down on one side. He characterizes the list as “short,” but it doesn’t look particularly short to me. Much of it will be working on review articles and shoring up the language in forthcoming student publications. He also has a poster presentation to finish up for this year’s ACSM annual meeting.
Yet there’s one piece on the horizon that seems to draw both his and my particular attention.
“I got to talking to somebody only last week or the week before about this paper on serendipity and science,” he says. (He’d written it seven or eight years ago and set it aside.)
“I was talking to one of my old mentors, David Costill, about it … and I went out and reread the thing and said, ‘Wow, this is sort of good.’ So I’ve written to a couple of journals and said, ‘Look, I’ve got something that an old man writes when his old madness is coming out. But I think it might be interesting for students to read and for people to realize how much chance (or luck) plays in what we do.’”
He outlines how the stereotypical scientist lays out meticulously “calibrated” plans step by step.
“Well, that’s true,” he says. “But the good stuff goes around that.”
He cites Einstein’s revelation about the speed of light, which came to the young physicist while he was peering at the headlamp of an oncoming streetcar.
“I think that an awful lot of stuff — certainly for me — that I suspect more than most people will admit to, comes from some accidental thing that happens,” Foster says.
Yes, that’s true. But for such serendipity to lead anywhere? A particularly gifted person must be paying attention. Someone with insight, intuition, patience and the doggedness to follow up with the necessary legwork.
Someone a lot like Carl Foster.