Exercise As Breast Cancer Medicine

Jamie DePolo: Hello. As always, thanks for listening. Dr. Christina Dieli-Conwright is an associate professor of medicine at Harvard Medical School and a researcher at the Dana-Farber Cancer Institute. Her research uses an exercise as medicine approach, and is focused on testing personalized exercise programs to improve cancer outcomes, especially breast cancer. At the 2023 American Association for Cancer Research annual meeting, she gave a presentation entitled, “Resistance Exercise is Medicine: Applications to Improve Health and Cancer Outcomes.” She joins us today to discuss the research. Dr. Dieli-Conwright welcome to the podcast.

Dr. Christina Dieli-Conwright: Thank you so much. It’s a pleasure to be here.

Jamie DePolo: So, to start tell us how you came to study exercise as medicine. Where did that come from?

Dr. Christina Dieli-Conwright: Sure. Sure, that’s a great question and quite frankly a personal question. I had always been very active in different types of physical activity. I was a dancer growing up as a child, did sports recreationally through high school and through college, and so movement has always been quite a big part of my life. That was inspired by my parents who were also quite active. And so, when I realized that studying things like kinesiology, which is the study of movement, is such a thing, in college and tying that into biology, I was really turned on to focus on that area. 

And even more so when I learned that there was a relationship, really driven by epidemiologic studies, that showed that physical activity can reduce both the risk and the recurrence of certain cancers. Then I really started to put the pieces together that this could be something that I could build a career off of. And importantly with that, as I’ve been building my career, I’ve really been inspired by the patients that we’re able to impact directly. Because my lab does do supervised exercise intervention, so we’re working very closely with the patients on a day-to-day basis and so it is very inspiring. 

Jamie DePolo: Oh, that’s great. Now, I have read a number of studies showing that exercise can help ease breast cancer treatment side effects like fatigue, and bone and joint pain, as well as improve people’s sleep and their emotional and mental health. So are there specific aspects of how exercise can help that you’ve studied? And have you found any new benefits as you’re conducting your work?

Christina Dieli-Conwright: That’s a great question as well. Yes, we have studied many of the symptoms and side effects that you mentioned, fatigue, we’ve studied osteoporosis, sleep, emotional and mental health. We’ve also studied metabolic dysregulation, which, in other words, is different biomarkers in the blood that are related to developing diabetes and heart disease. This is really the crux of our lab because for early-stage cancers in particular, individuals are often dying from heart disease rather than their cancer themselves. 

And so, we like to use exercise to offset these other comorbid conditions, such as diabetes and heart disease, and focus on things such as insulin resistance, body composition, such as how much muscle an individual has, how much fat an individual has, which those are drivers to diseases like heart disease and diabetes as well. Other things that we’ve looked at, you know, we have focused on some studies looking at muscle and its strength, cardiorespiratory fitness, or really that ability to do aerobic fitness. Other very functional type of measures, such as gait speed, or how quickly an individual can walk, how well they can do their activities of daily living. 

We’ve also been really interested in biomarkers related more directly to the tumors, doing interventions earlier on, meaning very soon after diagnosis before surgery, which we call that pre-habilitative exercise. Also, importantly, we’ve been looking at cognitive function and really tagging into what’s often referred to by patients as chemo brain and thinking about ways that we can prevent that by intervening with exercise during chemotherapy. And also using that not just to prevent chemo brain, but also potential neurodegenerative diseases that occur way later on down the line, perhaps as a result of chemotherapy. 

So, we do study quite a bit, quite a plethora of outcomes, as you can imagine, and we also manipulate the timing of the exercise. As I was alluding to earlier, pre-habilitation exercise before surgery or before treatment, exercise during treatment and then, of course, exercise post-treatment or post-cytotoxic treatments. And I’ll be honest with you, to date we have not had a negative study yet. Generally speaking, so long as the participants in our studies are adherent, meaning that they adhere to the exercise we’re asking them to do, then the results are always positive.

Jamie DePolo: Oh, that’s fabulous. I want to ask a follow-up question about the pre-habilitation exercises before surgery or before, say, chemotherapy. What is the goal of that? To make recovery faster, better?

Dr. Christina Dieli-Conwright: Yes. Absolutely, yes. So, the idea is that training an individual up for the event, so if we sort of equate this to an athlete, for example, you know we’ll take the Boston Marathon, for example, coming up this Monday here in Boston, you know you’re going to train the body physiologically to prepare for such an event. And in a case like a marathon or some type of competitive race, it’s almost like a trauma to the body. You can’t just run it, go out and run it without preparing for it physiologically. I guess you can, but maybe not as safely. 

And similarly with chemotherapy or a surgery, it’s important to train the body up to be able to withstand treatments better and keep the body stronger or promote the body to become stronger before treatment, so that the body can withstand the treatments from a better starting point, if you will. So, our premise is that we’re giving the individuals an advantage. They become stronger, they become more fit and then that way they can carry that into their treatments and feel better and withstand the treatment better. You’re exactly, right reducing hospital stays, reducing rate of infection, hopefully reducing treatment toxicities, et cetera.

Jamie DePolo: Oh, that’s fascinating, but it makes complete sense. Like you said surgery, chemotherapy they are insults to the body, so if you prepare your body for them, you’re likely to have a better outcome. I like it. I like it.

I also want to say I think all of us know deep down somewhere in our hearts that exercise is good for us. But a lot of people have a hard time, especially if they’re recovering from surgery, or some other treatments, or they’re having side effects, they have a hard time doing the exercise or sticking with the exercise, especially if somebody, say, is older and hasn’t exercised in a while or has never exercised at all. So, how do you help, in your studies, how do you help people get started?

Dr. Christina Dieli-Conwright: That’s a great, great question and so important, because we want people to feel encouraged to exercise and not discouraged. And what we do in our research, and perhaps if time permits I can speak to maybe from more of a lay perspective where individuals are not enrolling in clinical trials, but what we do in our research is we derive and deliver what we call orientation sessions. First off, as you likely know and the audience probably knows, for any type of research study the patients go through a consent process just like they would for surgery. 

We go through with them specific details of the study, what’s entailed, et cetera, and we do it in quite amount of detail, allow active listening questions, et cetera, so that they understand what they’re going to be signing up for. In addition to that, what we do is hold these orientation sessions, whereby we take the patients through exactly what to expect during the exercise, how to use the equipment, how long the sessions are going to take, how to do the exercises. So, it’s really giving them a quick snapshot of what the session is going to look like, but it’s taking a little bit more time and caution. And that we allow for questions, explain exactly what we’re doing before just throwing them right into a session where, you know, they’re heavily breathing or feeling discouraged because the, you know, muscle burning pain for resistance exercise is too extreme, et cetera. 

So, we ease them into it very carefully, very slowly. We also use an approach often referred to as exercise progression. In other words, we start at a certain level relative to the patient’s baseline fitness and we slowly and gradually progress from there. And that prevents individuals from becoming injured, from a psychosocial standpoint it prevents them from becoming discouraged or too fatigued from the exercise, and it really helps physiologically their body to respond linearly to exercise so that they don’t plateau. So, for example, if we were going to do aerobic exercise maybe we start somebody at 20 minutes three times a week with their heart rate at perhaps 40% of what their maximum heart rate might be, so that would maybe be low end of the moderate intensity. 

And then two weeks later, we might go to 45%, two weeks after that 50%, two weeks after that another 5%, et cetera, just depending on the study and what the goal is. And again, that allows the patients to ease into the exercise safely, but then also to continue to stimulate their body physiologically to respond to the exercise. So, having that progression in place, and then also taking the time to do orientation sessions where, if you will, it’s really like a tour of what their exercise sessions are going to look like, I think are really, really important. Lastly, I’ll just add that our study, our research lab in particular, uses an exercise paradigm with supervision. 

So, all of our exercise sessions, excuse me, are supervised by exercise trainers and in doing, using that type of a paradigm, we are there one-on-one to support the patients with their needs. Modifications, maybe if they’re experiencing an excess of chemotherapy side effects on a given day and the exercise needs to be modified, so that they’re still doing something, and they’re still showing up and coming with us, but we might ease back a little bit in order to accommodate that. It also builds a relationship from a psychosocial standpoint. Patients become very motivated when they know that they’re meeting with somebody to do the exercise with, almost similarly to personal training or hiring a private coach. And so, all those different types of supports are in place in order to encourage people to get started.

Jamie DePolo: Great. Now, what about somebody who is not in a study? 

Dr. Christina Dieli-Conwright: Great question.

Jamie DePolo: Yeah. Because certainly that all sounds fabulous and I know research shows that if you work out with a person or a trainer, you’re more likely to do it and stick with it because you’ve got somebody counting on you. But if you’re one person alone, and you haven’t exercised before and you want to get started, how do you, how do you do that?

Dr. Christina Dieli-Conwright: Yes, that’s difficult, but not impossible, not impossible. You know there’s a number of things that I recommend for people to get started. First of all, something is always better than nothing. And I think that’s really, really important to keep in mind, because if we keep referring back to exercise guidelines for cancer survivors, which are 150 minutes of moderate aerobic exercise per week or 75 minutes of vigorous intensity exercise per week, plus two resistance exercise sessions. I mean, just the amount of time that it took me to say all that, I mean, that can be very discouraging. Another way to look at it is 30 minutes per day. 

You know, no matter which way you spin it, it can be quite daunting for people to think, oh, I have to do all of this in order to prevent cancer, all of this in order to maybe survive longer, things like this. So, we just encourage patients to keep moving, something is better than nothing. And quite honestly there’s quite a bit of literature that’s coming out now to support even just interrupting sitting time per day is going to be impactful on mortality and other cardiovascular disease risks. Because you know we’re in an age of technology now, especially post-COVID, where you can, you know, you can be on Zoom or different types of video chats all day long without really ever having to get up. 

And so, first and foremost, something is better than nothing, move more, sit less, and consistency is really, really key. I think beyond that or deeper than that, is finding that motivating factor. So, as we know, exercise is a behavior just like food consumption. It’s also a very personal journey for many, many people. Some people really like it. Most people, to be quite honest, don’t really like to exercise. It takes time, it can cost some money, and it really can just depend on what knowledge an individual has on how to exercise. And so, finding that motivation and then combining that with what resources do you have at your disposal. 

So, there’s always going to be people who might be more motivated than not to do group exercise, join a facility where they can do group exercise at a certain time and that holds them accountable. So, they’re motivated by working out in a group. I always encourage people to maybe find a buddy, or individuals may be motivated by a pet if they walk their dog or walk their animal, but finding that motivation piece is really, really critical and that is not a one-size-fits-all approach. It really depends on the person. I can tell you from our observation of patients who finish our studies and re-enter into the real world, if you will, that oftentimes doing something like walking very consistently that doesn’t cost a lot of money is generally quite sustainable. 

And so, I think finding something, again, that you can go back to and be consistent at is so, so important. Because what we don’t want to happen is for an individual to say, okay, well I feel like I have to join a gym or buy a Peloton or do something very high-end, and maybe do it for a little bit, realize it’s not sustainable and then just go back to being sedentary. And so, finding that motivation, finding the resources. And I will say we also have reported that the No. 1 barrier to exercise, regardless of race, age, diagnosis, et cetera, but what patients tell us is their No. 1 barrier is lack of time. And this is really a hard one…

Jamie DePolo: Yeah.

Dr. Christina Dieli-Conwright: Because as an exercise physiologist I can’t necessarily carve out time for everybody and bottle it up for them. But it is, it is a game of give and take a bit, so finding when in your day do you have time to do this. Maybe you break it up, morning, lunch, after dinnertime. I know quite a bit of professionals in my, in my field of work do it early in the morning before they go to work, but for some that disrupts sleep and they may not want to do that. So, it’s, it’s a complicated question. I don’t have a straightforward answer for you. It’s more just thinking about resources, finding that motivation that gets somebody going day to day and just sticking with it, and not overthinking about, oh, I didn’t get my 30 minutes today or I didn’t get to 150 minutes. Just doing something is going to be better than nothing.

Jamie DePolo: Yeah, that makes good sense. I do want to ask, what about women who are worried about exercise either triggering or making lymphedema worse? That seems to be a fear for a lot of people. 

Dr. Christina Dieli-Conwright: Sure. Sure, absolutely, absolutely and rightfully so. As well all know there was the PAL [Physical Activity and Lymphedema] study that came out many years ago now, led by Katie Schmitz that was really the inaugural study to demonstrate that specifically resistance exercise was not going to be harmful or exacerbate lymphedema, and that still holds true. We assess lymphedema throughout all of our breast cancer studies, more as a safety measure, to basically confirm and sustain those results of the PAL study and to ensure that the exercise we are prescribing is not harmful. Even though we know it’s not going to be, we like to continue to assess it. 

Really, exercise can be very beneficial for lymphedema. You know the lymphatic fluids in the lymph system are going to move with exercise, especially with upper body movement. A really key factor, though, is making sure to, as I was referring to earlier, to progress exercise very slowly. So, not jumping in and thinking that you need to lift very heavy weight to strengthen the arms or even the legs from the get-go, but thinking about starting probably a little easier than capable of and taking about two to three weeks in between increases in the amount of weight that is lifted. And as long as that progression is done slowly and safely, then there should not be any concern about lymphedema, and in fact that exercise should actually be quite beneficial.

Jamie DePolo: Okay. Okay, thank you. Very good to know. And I do want to ask, too, does the type of cancer or the stage of cancer matter when it comes to exercise? So, in your studies, if someone’s been diagnosed with metastatic disease does their exercise program look different than someone who has been diagnosed with early-stage disease? Or is it really based on a person’s age and their level of fitness? 

Dr. Christina Dieli-Conwright: So, I’ll answer this first from a research standpoint. From the research we do in our lab, I would say it only differs depending on what our goal of a study is. So, as an example, we have a study ongoing now in individuals with metastatic pancreas cancer, and our goal is to maintain or preserve muscle mass in a population who often sees quite a bit of muscle wasting as they go through chemotherapy. So, in that sense, we are doing resistance exercise. We actually happen to be also doing a protein supplementation with that as well. And that program is going to look very different than, let’s say, early-stage breast cancer intervention, where we might be intervening for diabetes risk, because we might do more aerobic and resistance exercise for that outcome related to diabetes. 

So, from a research standpoint, it really depends on what we’re trying to target specifically within the patient population. From just a very more broad survivorship standpoint, I would say no, it doesn’t. It depends more on what an individual is capable of and perhaps more what their goals are. Some people do have goals that might streamline them a little bit more towards weightlifting. Maybe they want to build muscle mass. We see this a lot in our prostate cancer studies where men are on ADT where they see -- androgen deprivation therapy -- where they see quite bit also of muscle wasting, especially with that lack of testosterone stimulation to the muscle. 

So, maybe there’s more of a resistance training focus on their exercise program than on the aerobic exercise side of things. But again, it is all relative to their level of fitness. So, I would say that doesn’t necessarily need to look different, but it might, based off of, from a research standpoint, one, the goals of the research, or two, from just a broad survivorship, you know from any individual looking to exercise, it might be based on their personal goals.

Jamie DePolo: That makes sense. That makes sense. And finally, I want to ask about resources for people if they’re out there listening and they want to get started. You know, are there online things? Does it make sense to try a couple of sessions with a trainer to get started and perhaps assess goals? What would you suggest? 

Dr. Christina Dieli-Conwright: That’s also a fantastic question. A couple of things that I would suggest. You know, I do think that knowing how to exercise properly and getting the information, even for just building self-efficacy, so that somebody feels confident going out and taking on exercise, then hiring a trainer, if possible, might be a good start. But that’s generally not sustainable. Trainers can cost upwards of hundreds of dollars per session nowadays, and again that may not be sustainable. Some gyms, however, do have some introductory sessions with exercise trainers. Beyond that, there’s so many resources online now for free virtual exercise classes. 

For example, here at the Dana-Farber Cancer Institute, we have the Zakim Center and within the Zakim Center, which is our integrative medicine center, led by Dr. Jennifer Ligibel, there is a platform, if you will, of exercise videos that have been recorded since the beginning of the pandemic in a library forum that is free to anyone that can be, that are designed to be done at home. Another resource through the American College of Sports Medicine that is actually a registry geographically. So, on such a website, the Exercise Is Medicine website, you can actually put in your zip code and it’s designed specifically for cancer survivors. And once you put in your zip code it then populates a directory of exercise resources for cancer survivors. And I’m happy to share that link.

Jamie DePolo: That’s great.

Dr. Christina Dieli-Conwright: And that at least gives an indication of kind of where to look in the area where one lives and where there might be free or for-fee exercise resources. And it is updated regularly it’s just self-regulated or, excuse me, self-updated, by individuals who offer these types of programs that are asked to go onto this website to provide their information. Outside of that, you know, there’s definitely local resources. So, also just look into naturally, you know, especially for breast cancer, there’s a lot of fantastic dragon boat racing organizations out there that are really fun and very active to get involved with. As I’m sure the audience knows there’s also many different types of breast cancer walks, those are also really great and fun to participate in. 

So, really just digging in and looking for local resources just by a simple Google search could even go a really long way. And then I’ll just make a brief comment about equipment. Often exercise, especially resistance exercise, can get overlooked because of how daunting the equipment can be. Well, thanks to places like Amazon, this type of equipment, you know, can be delivered at your house for pretty reasonable cost depending on adherence to how much it’s actually going to be used, as opposed to just hanging laundry on. But, for instance, in our virtually-supervised exercise studies, we actually send patients a stationary bike, we send them adjustable dumbbells, and we also send them resistance bands. And all of that together is generally around $500, which is quite a bit of money, but if you think of that in comparison to things like Peloton or monthly subscriptions, or monthly gym membership fees. 

So, if individuals are motivated to workout at home, which again is not going to be for everybody, Amazon’s a great resource to find some affordable exercise equipment that’s not heavy or clunky and that’s not going to be really high-end or high cost. So, there’s quite a bit that’s really evolved over time, thanks to COVID, but even before COVID just as a result of technology. There’s a lot more mobilization, if you will, of virtual exercise and exercise platforms, exercise apps, things like that, that are available for people. 

Jamie DePolo: Oh, that’s great. Dr. Dieli-Conwright, thank you so much. This has been so helpful and I really appreciate your time.

Dr. Christina Dieli-Conwright: Thank you so much for having me.