Interviews, PeopleCardiac, Smooth, Skeletal, and Surf
On Muscle: The Bonnie Tsui Interview
Most people will know Bonnie Tsui as the bestselling author of Why We Swim. We know her as an enthusiastic surfer and a beacon of positive energy in the line-up.
Bonnie is a poetic and skilled storyteller who blends journalism and science-writing through a personal lens to bless her subject matter with the broadest appeal. Her 2020 book Why We Swim was critically acclaimed and went on to win numerous awards and accolades and become a bestseller. Her latest book, On Muscle, published April 22 this year, holds relevance and appeal to an even broader audience than Why We Swim did, because whether or not we swim, each and every one of us has and relies on our muscles. They make our heart beat, push food through our digestive system, and most obviously, they move us.
Bonnie’s books are reflective personal projects, and it’s therefore no surprise to us that for her as an avid and almost daily surfer, surfing appears discretely but repeatedly throughout On Muscle.
As Bonnie prepared for the publication of On Muscle, Surf Simply Magazine’s editor Mat Arney spoke with Bonnie from her home in the Bay Area to talk to her about her latest book, to dive a little deeper into the surfing references within it, and to discuss the various muscles that we use in our surfing lives and why.
One of the things that got me thinking when I was preparing for our call was the often-presumed similarity of movement between paddling a surfboard and freestyle swimming. People often think that being good at one will make you good at the other. And you and I both know that if you stick a surfboard in the way, it’s a very different story. So, I was going to ask: What was your physical experience, as a lifelong swimmer, of becoming a regular surfer? Was there a moment with your pre-existing knowledge and understanding of physicality and musculature when you thought, “Oh, hang on, this is different”?
That’s such a great question, because it has sort of evolved for me. When I first started surfing, I didn’t know anything about surf paddling. I thought, I’ve got this, and I would just swim it. I think I would kind of over-paddle, right? I mean, that’s what so many people do when they first start out. I would often get ahead of the wave, I had no sense of timing or anything like that. I didn’t get tired because I had that conditioning from swimming, but I also didn’t understand at that time (certainly upon reflection and in retrospect) that surfing is so much about timing and precision and knowing where to place yourself as the wave is coming. It’s all about efficiency.
I just had a session a few months ago with Rob Case. Case is a surf paddling coach, and has worked with tons of top surfers, and he’s a swimmer. He’s now a paddle coach to the stars. He’s coached a lot of surf pros, but also recreational surfers as well. A surfing friend of mine introduced me to Rob in the water, and we became friendly. Then I went up to his place where he has an endless pool in which he does assessments. It’s really cool because he’ll put sensors on your hands and have cameras, so you can really see your stroke efficiency and paddle technique. I was terrified because, you know, after being a swimmer my whole life, it’s not just about swimming, but also realizing that swimming and surf paddling can sometimes mess with each other. Because I’ve been surfing so much in recent years I also knew it was affecting my swimming technique! I thought, okay, I have to choose right now what to focus on. I’ll swim for conditioning, but I’ve noticed that my shoulder has been hurting. What can I do about it?
Having swum my whole life and then surfing so much in the last few years, I’ve been thinking about the overuse injuries. If you're not careful with technique and conditioning and strength training, you can really screw up your joints. I thought, “How can I avoid getting rotator cuff surgery?” So, a couple of months ago, I did a technique session with Rob, and I started doing more concentrated weight training for my shoulder. Now, I feel like a million bucks.
I read the chapter on shoulders yesterday, and I’ve had two decades of tricep issues. For years, I didn’t realize that was probably linked to a shoulder and rotator cuff problem. It’s been one of those ongoing minor issues, and now, with two kids, I surf less, but I still get these flare-ups. If there’s a good swell and I’m surfing a lot then suddenly I have a tweaky arm again. It took a long time to realize it was actually a shoulder issue from overuse.
I feel you on that, oh my gosh! So, you just read that shoulder chapter, so you know how many muscles work on your scapula. It’s all so connected. Sometimes the pain you feel is referred pain; it’s coming from somewhere else. Shoulders are so delicate, and as I learned while researching and writing that chapter, if one of those muscles goes out of whack, something else has to compensate. The range of motion in your shoulder is huge, and if something goes wrong, you’re in trouble.
A lot of shoulder injuries are hard to pinpoint, and it takes time for a physical therapist to figure out the root cause of the pain. As we get older, we become hyper-aware of these things. We want to continue doing what we love physically for as long as possible.
Writing this book at this stage in my life was actually a blessing because it made me think more carefully about all of this. I’ve become more understanding that the time and commitment you put into weight training or physical therapy is an investment in your future self. It’s not just about surfing a few hours a week, but also about being able to lift your kids or reach for a high shelf without pain. I know you’ve experienced that moment when you think, “Oh no, I can’t do this anymore.” We take certain things for granted, and when you realize you can’t do them with the same agility or flexibility, it’s scary. We have to move past that “invincible” phase of youth when we think we’re superhuman. But younger athletes, even recreational ones, are more aware of strength training and conditioning now. It’s part of the conversation. When I was younger, it was just about the sport—surfing, swimming, or whatever it was—but now, it’s changed.
This got me thinking about how we balance strength with mobility. How do we avoid the situation where we’re either muscle-bound or incredibly flexible but without strength through our range of motion? That balance is essential. Through all my research, I’ve learned from trainers, anatomists, and coaches like Rob Case. The privilege of having access to all these experts has been amazing. I’ve observed dissections of bodies and gotten to do assessments with coaches who work with pro athletes. This knowledge, though, isn’t just for athletes at the top level. It’s something everyone can use.
In the book, there’s a section on flexibility and how different bodies adapt: differently abled bodies, yoga, other sports, and how aging affects flexibility. It’s all about how we evolve in our physicality as we age.
You know, we all exist on this continuum. Our bodies exist on this continuum, from able to disabled. One thing that I learned from this adaptive yoga instructor, and I felt it was really profound and I will never forget this, he said, “Disability is something that happens slowly or suddenly.” He said, “Suddenly” could mean something like an accident or an injury. He was paralyzed from the chest down in a car accident when he was 13. He said that’s an example of something happening suddenly. But he also said that disability can happen slowly. If you have the great fortune to age and live to an old age, that will happen to you.
So I think understanding that we all exist on this continuum together, all of our bodies, and we’re always moving along it, was really eye-opening. It sounds so simple, but it was like realizing that you have to accept all of those versions of yourself—along that continuum of age and ability—and also figure out how to be the best version of yourself and support that movement that you have in your body at any given time. To me, that was wisdom. Hard-earned wisdom.
Yeah, I took a note of the closing sentence of one chapter, about “trying to be an athlete at life”, and I thought, “Yep, that’s it.” As we age, if we end up in circumstances where we're less mobile, we still want to perform within that body, within that sphere of movement, and be in that health and mobility sweet spot.
I tried to avoid using the word “optimize” because I think that language is often co-opted by bro-y tech life-hackers. But it is about figuring out how to be the best version of yourself. I don’t know how to talk about that without sounding kind of woo-woo or life-hack-y, but I think with muscle and strength, maybe that’s a more fertile ground because people haven’t talked about it as much. So, I wanted to do that with this book. I wanted muscle to be something accessible to everyone, strength to be something accessible to everyone, and owning that strength to be something accessible to everyone.
If you ask 20 people on the street what they think of when they hear the word “muscle,” chances are the vast majority of them are going to say something like, “Oh, bodybuilder, someone lifting weights at the gym, a CrossFit person, Arnold Schwarzenegger, the Incredible Hulk.” Those are the associations most people have. And yet, it should also be your grandmother, working on strength training so she can do her line dancing with her group of ladies.
So, I don’t know, I wanted On Muscle to be something that everyone could see themselves in. I think it’s similar to the goal I had with Why We Swim. In the five years since that book came out, one of the biggest compliments I get is from people who say, “I didn’t think I was going to like this book because I hate swimming or I hate the water or I’m not a swimmer.” But by the end of the letter, they say, “I finished reading the book and I got a membership at the Y,” or “I started swimming again.” That’s the biggest compliment to me because I’ve told them stories that made them think about swimming in a different way, and thus, think about themselves as swimmers in a different way. Who is a swimmer, and who gets to be a swimmer?
Similarly, I want this book about muscle to invite people who say, “I don’t need a book about muscle,” or “What does this have to do with me?” Maybe they pick it up, start reading, and some of these stories sort of tickle their imagination. Then they get to the end and realize, “Oh, maybe that is me.” That’s my dream, my hope—that if that happens for even one person, I’ll be very happy.
Making it an accessible endeavor has been my goal, I guess. Through all the stories I tell, that’s how I think about the world too. I wanted to write a book not just about the tangible aspects of muscle—the things that move us around—but also about the metaphorical meaning of muscle, the metaphorical resonance of it. So much of our language revolves around these words that are muscular, talking about traits of muscularity, and we don’t even realize it. I think that’s really cool.
Were you surprised by any of the avenues you went down, any of the activities you covered when researching and writing? Were there any stories or characters that went away from what you expected when you were initially putting the project together?
That’s a really good question, and I wanted to be surprised myself. So when I come across a story or a person who I think would be a wonderful character to include, someone who could illuminate things in a way that would also surprise readers, I get really excited. Like when I heard about and read about Jan Todd, the powerlifting pioneer, sports historian, academic, and event designer for the Arnold Strongman competition. She does all of these things, and she was the person who physically inhabited the body that came with it. She could talk about what that felt like while intellectually interrogating it. She’s also a woman, and I loved hearing her perspective about what it was like at that time when there was no Title IX, and people looked at muscular women in a derogatory way. She’s just such a good storyteller, and when I met her and started talking to her I knew she could be an entry point for the book because she is someone who both subverted the sort of male-dominated masculinist association with muscle, and it's something that people can understand - she lifted some really heavy rocks.
You kind of want a story that is something people can understand to bring you in, and then you start leading them to unexpected places. As you move through the book, it's like jumping Double Dutch, or the Great Lake jumper who jumped into Lake Michigan every day since the pandemic started. That was a path to joy, and people watching him jump understood that what they were watching was something they needed emotionally because it was freeing and joyful. When we jump, that also connects to something—jumping is such a foundational movement in human development, and yet it’s also something we don’t do as much as we get older.
When you mentioned Jan there, I thought about another part in the same section where you reference how in the past female athletes would hold back on their training and perhaps not train to peak performance because of their concerns about the impact on their physical appearance. Do you think we're at a point as a society—and I think also perhaps the question goes to within surfing, where strong women and their physical appearance can be celebrated, whether that's in sport or in society?
We’re getting there. I mean, we're getting closer, but as any observer of online trolling or certain social media accounts knows, there’s a certain percentage of people who you will see trying to tear athletes down because of the way they perceive their appearance, and they think that’s okay or they think it’s okay to comment on women’s bodies. I think that we’re still far from a place in which that doesn't happen, and I don’t think that will ever come, really. But I think we are moving away from where that’s acceptable for everyone. I was just reading a story yesterday talking about even just in the ‘90s, or the early oughts, where a mainstream publication would comment on a female performer or female athlete’s body in a way where you’re kind of like, “Wow, I can’t believe they said that,” and yet it was only like 20 or 25 years ago. I think we’re moving in the right direction in many ways, but of course, it’s still there.
I also think the more female athletes who are excelling and visibly strong, the more acceptable it becomes. When you watch competitive surfing, you see athletes like Carissa Moore or Caroline Marks who are just so athletic, and so powerful. When they surf, it is strong. It’s athletic in a way that I think women in surfing did not have as a model until fairly recently. Similarly, in the last two years, Ilona Maher, a rugby player breaking out in the Olympics is a social media star now, and she’s able to talk about women’s bodies and do all these things in a very talented, charismatic, funny way. She’s able to connect with her audience in this really wonderful and remarkable way. She’s now the most followed rugby player in the world, but she also has been occupying a strong body since she was a kid and is able to talk about what it’s like to be criticized for that and be the role model for other girls coming up in sport who see her now. Ilona Maher didn’t have an Ilona Maher when she was growing up, and the fact that girls now do is spectacular. It cannot be overstated how important it is to have female athlete role models like that for younger girls and women. It’s so great, and I think that’s partly why she is so beloved.
You mentioned earlier young athletes for whom strength and conditioning is just a part of what they do, but for a long time, and I stick my hand up, one trained for an activity by doing that activity. I wanted to circle back to that.
Your closing chapter is about the push-up, and as I was reading it I realised that as a teenager I would have told myself ‘I am not good at push-ups.’ But actually, we all do quite a lot of push-ups when we go surfing. Every duck dive, every pop-up is a push-up. Did you come across other examples of traditional strength and conditioning exercises that sneak their way into activities?
I was talking to Kevyn Dean, the medical director for USA Surfing, and all of these trainers and orthopedists, sports medicine guys who were working with the USA surfing team. He was the one who, when he was talking about jumping, really got me thinking about it being a foundational movement in early human development and how the vertical jump, vertical leap, is like this metric for performance, for fitness. And I thought, “Oh, that’s so great,” because when you look at it across sports and different body types, it’s just a very useful indicator of explosive power, muscular strength, and agility.
I was thinking about this, and I was like, “What about surfing?” He’s like, “Yeah, you’re constantly pushing off the surface of your surfboard” And then I was like, “Oh yeah, we are totally doing that all the time,” even when we’re surfing, as well as just jumping off the board at the end of a ride. It’s this compression and extension, and sometimes your feet aren’t leaving the board until you kick out or whatever, but it is that same compression, explosion, compression of jumping. It’s just that the board follows up underneath your feet, right? And so surfing is funny and interesting and weird because you have this piece of equipment you have to incorporate as part of your body. I still struggle with it, understanding the physics of how this board attaches to me and what I have to do in order to make it so that I’m not divorced from it, you know.
When Kevyn was telling me this was when I was doing this training regimen with him at Kobe Bryant’s Mamba Academy, at the same time as all these kids, these junior team athletes. Caitlin Simmers was one of the athletes. She was 13 then, and now as I’ve been watching her over the last five, six years, I’m just like, “Oh my God, I got to do this training stuff with Caitlin,” and she was this 13-year-old grom, but amazing, right? I was talking to her, and she was kind of reticent. She still kind of is the same, but she’s so strong, like so athletic with her surfing, and it’s been really neat to be like, “Oh, I was there working out with these kids at that time,” and then now look at them. They’ve incorporated these training methods into their lives. Lessons, as they've moved on in the world of surfing and competition, include things like jumping, box jumps, and landing on one foot or another. Just agility stuff. This includes ankle flexibility and ankle strength, strengthening muscles I didn't really think about much before. I don’t know if you do, but the muscle support in your ankle is important.
We did an article, Kim wrote it about a year and a half ago, about a study in Australia on ankle strength. They simulated landing airs and how ankle flexion works. They found that the most successful airs are landed with the knee further forward over the ankle. A lot of the stuff John John Florence has put out recently also touches on ankle strength, knee strength in compression, and the way John John approaches it.
I can't believe that this kind of analysis is still quite new. As Kevyn had told me, even five or six years ago, he said they were just starting on this stuff. We’ve come so far now that John John would be talking about it publicly and people would actually pay attention. But in retrospect, strength and conditioning wasn’t applied to surfing for so long, so surfing was pretty far behind. It makes sense though—when you're landing with compression, it’s such a huge force. Your ankle cannot take that unless it’s prepared for it.
I've actually been noticing this more in recent years. In the last year or two, I’ve been going shorter on a board and trying to be more aggressive with maneuvers. After a surf session, I’ll think, “Why is my ankle swollen?” I didn’t even think about landing with any particular force at the time. It doesn’t feel acute in the moment, but then I’ll come home and think, “Huh.” I have a left ankle I sprained really badly when I was about 22, and it’s never been the same. The tendons really ripped, the ligaments got messed up, and it’s more prone to swelling now. But I understand that it’s because I’m compressing. Even just jamming it in a turn, like an on-rail cutback, requires that position and force over time. You have to consciously hold it, slow down, and not snap it around. That’s a time when your ankle is really pushing against the board, hyper-flexed. Your muscles are trying to hold it, but there’s no direct impact; it's all about the pressure.
I think all of this shows that there are muscles and movements that support surfing. Strengthening those muscles and working on mobility—functional mobility and functional strength—is key. When I talked to this trainer I work with who had worked with a lot of swimmers, particularly at Cal Berkeley, he wasn’t too familiar with surfers. He understood the shoulder mobility issues, especially where you feel pain. One of the first sessions with him, he had me work on this tiny side movement of the shoulder, strengthening a smaller muscle that doesn’t get as much attention. It wasn’t about lifting huge weights or trying to do a big movement. He said, “Let’s focus on strengthening this muscle because it’s often neglected when you're doing front pulls and pull-downs. It supports a full 360-degree range of movement.”
Strengthening those side shoulder muscles has been so helpful. When one muscle fatigues, the other supporting muscles help to do the work. We all know that if one muscle gets fatigued and there’s no support, you start compensating and doing bad things, which leads to injury. So the stronger the supporting muscles are, the better off you are. This may seem obvious, but it’s not something people have been doing. If you don’t have someone who can talk to you intelligently about this stuff and show you how to do it, you’ll never really know how. That’s why it’s so important to have these conversations. John John talking about this stuff makes people (surfers) pay attention.
One of the things that I learned about professional surfers is that a lot of them don’t like to talk to talk about their training publicly. It’s something that stays in the lock-box with their teams. Kevyn said, all of the stuff that he’d talk about with these different surfers, they’d kind of be looking over their shoulder at the other surfers kind of not wanting them to know what they were doing!
I think the more information that is shared, the more conversations we can have about injuries, recovery, and injury prevention, the better. That’s where someone like Rob Case is so interesting. He’s been making paddling more accessible to more people. His services aren’t cheap and aren’t accessible to everyone because not everyone can come and do a paddle session with him or go to his camps. But he’s written a book, like his paddle coaching 101, that he wants to be accessible to more people. If they can’t attend his coaching, at least they can learn something from the book.
The physical activity of surfing must be about 98% paddling—either paddling out or paddling for a wave. There's a difference between the slow, endurance paddles and the fast, sprint paddles needed to catch a wave. When you’re actually riding a wave, you’re not really using your shoulders in the same way. You obviously use your arms for placement and flow, but the shoulder work is mostly in the paddling, not in the act of riding a wave. Surfing has a unique combination of endurance and explosive elements.
Yeah, you have long, slow paddles, like paddling out, and then fast, burst-like paddles when you go for a wave. I remember one day when I surfed at Ocean Beach. It was just brutal that day. My friend and I paddled out, caught one wave each, and then went for a coffee because it was so bad! The period was really short, and we were out for maybe 30 minutes total, just paddling the whole time!
I guess it’s not so much about the physicality and muscle element, but you mentioned in the book that while you were writing it, you were regularly surfing at dawn. Surfing pops up throughout the book. It's a book about muscle, but you’re writing it and it’s got your personal story in it. As an author, what does that time spent exercising in and spent in the ocean, do for you?
Oh, gosh, it restores me to a place of equilibrium. It’s time that feels expansive, you know? I especially love early mornings for that reason. It’s quiet, and it’s dark, and as the sun comes up, there’s a sense of wonder and awe. There’s also this feeling that the world is waking up and you’re there to witness it.
As an author and a journalist and observer of the world, it feels very special to be awake during that time, witnessing it. It’s like witnessing humanity waking up. And also, being out in the ocean, I think anyone who does it regularly knows it makes them better. It helps you understand the vastness of the world and our tiny speck of existence in it. That’s really valuable, especially as a writer, to understand both the large and the small—the scale of being and what your place is in it.
I guess it’s the best way I can put it.
Fantastic. Thank you so much, Bonnie.
On Muscle was published on April 22, 2025
Order your copy here (USA) or here (UK)
Bonnie Tsui is a longtime contributor to The New York Times and the bestselling author of Why We Swim, a New York Times Book Review Editor’s Choice and a Time magazine and NPR Best Book of the Year. Bonnie is also the author of American Chinatown, which won the Asian/Pacific American Award for Literature, and Sarah and the Big Wave, a children’s book about he first woman to surf Mavericks. Her work has been recognized and supported by Harvard University, the National Press Foundation, the Mesa Refuge, and the Best American Essays series. She lives, swims, and surf in the Bay Area.
Surf Simply would also like to thank David Gray and Finisterre for sharing photographs of Bonnie at home in the Bay Area. Listen to Bonnie talking about her book Why We Swim on their Hell Or High Water Podcast.