The Science of Post-Workout Recovery

Author, Christie Aschwanden joins Get-Fit Guy to discuss whether some of the most popular recovery methods, and devices actually help you bounce back from a hard workout or just add stress to your day and your bank account. 

Brock Armstrong
21-minute read
Episode #461

Let's take a light-hearted guided tour of the wacky world or cryotherapy, float tanks, not-so-hot saunas, and even space-age pajamas. We'll also chat about recovery, and what it means for your fitness routine.

Christie Aschwanden is an award-winning journalist who has been a lead science writer at FiveThirtyEight and the Washington Post. Her writing has also appeared in Outside, Discover, Smithsonian, and O. Christie is also the co-host of Emerging Form, a podcast about the creative process. 

In the world of fitness and sport, Christie was a high school state champion in the 1,600-meter run, a national cycling champion, and an elite cross-country skier with Team Rossignol. She now lives and occasionally races in western Colorado. I recently had a chance to interview her about her book, Good To Go, What the Athlete in All of Us Can Learn from the Strange Science of Recovery.

In Good to Go, Christie looks at some of my favorite recovery tricks, methods, and devices with what I would describe as an air of skepticism but also true science.

Back in the day, recovery used to be relatively simple. We would just take a day off to rest and let our bodies get ready to perform again. But lately, recovery has become a costly source of stress. As Christie says in the book, we have “managed to make every aspect of it … vastly more complicated, expensive and time-consuming.”

My interview with Christie is transcribed below. But, as always, I encourage you to listen to the podcast audio to get the full intent and humor. Just click the player above, or listen on Apple, Spotify, or your favorite podcast app.

Interview with athlete and author Christie Aschwanden

Brock: All right. Here we go. I have Christie Aschwanden on the line with me right here, but before we get into all the nitty-gritty about recovery and what we should and shouldn't be doing, Christie, can you give everybody just a little bit of your background and where you came from?

Christie: Sure, no problem. I started off as a runner. I've been a lifelong runner, actually. It's the one thing that has been sort of the continual thread throughout my athletic career. I started running in high school, went on to become a runner at University of Colorado, but during my collegiate career I actually got injured and started cycling and so I joined the collegiate cycling team. Started doing that. I also learned to cross country ski, which is something that I had never done before. I had grown up Alpine skiing, but anyway, after college I bike raced pretty seriously and then I went on to join the Rossignol ski team, so I skied on a pro team traveling all over North America as well as Europe racing for that.

Brock: Wow. So definitely a lifelong athlete of one sort or another, which isn't a surprise having read most of your book, Good to Go: What the Athlete in All of Us Can Learn from the Strange Science of Recovery, I have to confess, I haven't quite finished it. It is a great read and it's really, really interesting stuff but it's pretty dense.

Christie: Interesting. I haven't heard that before. That's interesting to hear.

Brock: Well I'm the guy who follows every single footnote, too, though.

Christie: Well I'm glad to hear that because I do have a lot of footnotes. I do a lot of sourcing and all that, so it pleases me to know that you're following those because I put those in there in hopes that people would look into all of those things.

Brock: That being said, I'm not quite finished the book because there is a lot of stuff in there. There is a lot of information, so we're going to try and keep it a little bit higher level and not get bogged down in the weeds ... because we sure could. I mean, just icing alone, we could do three episodes about! But I guess before we really get into stuff, why did you decide to write an entire book, and really heavily researched, and it seems like you probably spent years talking to people getting the stories and stuff for this book, but why recovery? Why was that such a passion for you?

I had a history of over-training, a lot of injuries and illness. Recovery was really one thing that I never got right.

Christie: It seems kind of weird on the surface right? A whole book about recovery. But that question has a couple of answers. I think the first answer is just going back to me and my background. When I look back on my athletic career, recovery is really the one thing that I sort of never really managed to master. And when I look back at all of the things that happened throughout my career, I had a history of over-training, a lot of injuries and illness. And I realize now, and I eventually learned this and came to understand this about myself in the latter stages of my career, that recovery was really one thing that I never got right. And it was something that I didn't give as much attention as it probably deserved. And I fell into that very common pattern of thinking that more is better and I just need to work harder and that the payoffs are always going to be better performance when in fact, I know now and learned during my career that very often rest is the best thing you can do for your performance.

So, that was the first thread, but then the other thing is sort of in the time between when I stopped being a serious athlete and now, what I've noticed is that it has become sort of this product and this subject of very intense marketing and, as a science journalist by vocation, this is the kind of thing that I look into all the time. And so I was really interested in sort of the marketing of recovery and the genesis of all of these products and services that are purporting to improve recovery and to help athletes master recovery. I feel like if I had been an athlete at the time when these things were out, I may have been interested in trying some of those. So I did that as a journalist and I really approached recovery and I approached the topic as a journalist to really say, what do we really know here? What does the science say, and does any of this stuff really work?

What does the science say? And does any of this stuff really work?

Brock: And that is the biggest question right there. Does any of this stuff really work? I think you said in the book it's like a $5 billion industry at this point. The recovery industry or something like that.

Christie: Yeah, it's really hard to put a number on it because there are so many different types of products that fall under this, and there's so much different kinds of marketing. No one's actually tracking it. There are all these economic groups and things that track these things, but it's not a category in and of itself. So you have the hydration stuff, you have all the sort of physical therapy type tools, you have nutritional products. And then all kinds of things like cryo saunas and infrared saunas and pneumatic compression boots and a lot of devices and products like that as well.

Brock: Yeah, it really does go all over the place. And one of the common themes that comes up on this podcast, and in most athletes lives, or fitness people's lives, is there's sort of two problems as I see it, when people are getting interested in becoming an athlete or getting fit even, is that some people don't know where to start and other people don't know where to stop. And I think what we're going to talk about today is more for the second grouping of that.

Over-training is such a common problem, particularly among endurance athletes, although among strength athletes as well.

Christie: Yeah. Like I like how you framed that a lot and I have a whole chapter in the book about over-training and it's such a common problem, particularly among endurance athletes, although among strength athletes as well. And it's just something ... I think that it's a common kind of thinking that people fall into, which is more is better and their response to poor performance is more training. One of the most important things athletes need to realize and to learn is what it feels like for their body to be over-tired. What does it feel like to be under-recovered and when do you know that it's time to back off instead of push harder?

Brock: Well, and that leads really nicely actually into the next thing that I wanted to ask you about was who is it that really needs to worry about this type of thing? Is it just the professional athlete? Is it just the elite athlete or the weekend warrior? Or is it really anybody who's forcing their body or asking something from their body that's a little more unusual?

Christie: There's a tendency to think that recovery is only something that matters for elites or for people who are training a great deal. But it turns out that it can be very important for sort of weekend warrior types as well. Let me explain a little bit what I mean by that. There's a tendency I think of high-performance— I'm thinking of people who are in sort of high performance jobs, things that are very stressful or time-consuming or demanding. To do sports and to do fitness as sort of a side sort of thing or whatever. But they tend to pursue it at a high level, too, and wanting to do all that they can and that thing.

But what ends up happening is people sort of don't understand that, to their bodies, stress is stress. And so if you're in a situation where you're in a really stressful job, a really stressful time at work, maybe you have even personal problems at home, you have some other thing going on. Anything that is sort of stressing you out as we would say in sort of vernacular terms. That is putting stress and strain on your body and it is limiting your body's ability to repair itself and to do all these things that it needs to perform.

You really have to ask, What kind of strains and what kind of stress is my body under?

And so if you're constantly under stress, you may not be resting even though you feel like, well I didn't train yesterday, or I barely trained and therefore I'm resting. No, you really have to ask what kind of strains and what kind of stress is my body under? And frankly, training is only one of these types of stresses. And so it's really important to balance those stresses of life with the stresses of training. And in many cases, particularly for recreational athletes or for people who are exercising for health and for wellness, exercise may actually be a very potent form of stress relief, and that's great. But what can happen is you have someone who is exercising sort of for mental health benefits and stress relief and all of that, all of a sudden they decide that, well, I'm going to jump in and do a marathon or I'm going to train for some specific event.

And then all of a sudden the mindset sort of changes. And instead of this thing being a pleasure leisure time activity that you do for enjoyment, it becomes sort of another job or another thing that feels like an obligation. And that can really change how you are experiencing it as well. And so even though you may not end up increasing the amount of training by a large amount, the stress and strain that it's taking on your body might be increased. And so it's really important to just pay attention to how that training, that exercise is feeling to you, whether you're sort of giving yourself and your body downtime to relax in between bouts of exercise in between whatever other stressors are in your life. And so I would like to think of recovery as not just being something completely specific to sport, but really in a more holistic way that takes into account everything that's going on in one's life.

And so you can really think about recovery from the stresses of work, recovery from travel, all of these other things that are sort of placing demands on our body. Those things require time to give your body just time to rest and relax. And it really is, at the end of the day, recovery really is about rest and relaxation. So you have to be really careful about getting into situations where you've turned a recovery into its own source of stress and this other obligation that you feel like you need to do and that it takes as much time and effort and energy as your training, recovery should feel relaxing.

Brock: Now ,that actually leads really well into the next thing that I wanted to talk to you about is with some of these little bit kookier recovery devices that are out there, and I think I agree completely. If you're spending a whole bunch of money in a whole bunch of time, getting yourself to these spas, I guess you would call them. The recovery spas that are popping up all over the place these days can really be an added stress on top of the stuff. So I know you've used a number of things that I've also used, and I kind of wanted to get your take on things. Maybe we can compare notes on a few of them? Let's start with with cryotherapy. Can you describe what that is? Just first off?

Cryotherapy basically feels like standing naked in a blizzard.

Christie: Yeah. You basically stand at a metal drum. You're in there naked, and they turn on this liquid nitrogen and then let that out. And so it's extremely cold. It basically feels like standing naked in a blizzard. I don't know if that's what it felt like to you, but that's what it felt like to me. But you're only in there for a very short period of time. Less than three minutes. Usually two to two and a half minutes seems to be pretty standard and yeah, it gets really cold.

Brock: Yeah. So it's the, it's the vapor, not the liquid nitrogen. That's actually covering you. Otherwise you would freeze solid.

Christie: Yeah, I should clarify. Yeah, so it's the very cold gas basically that's streaming up and chilling your body.

Brock: In the book you talked about how it gave you a bit of a boost and you sort of felt, I don't think you said giddy, but that's what I sort of took away from it.

Christie: Oh yeah. I came out of there feeling like I was ready to kick some butt. I would say it was an adrenaline rush. It felt like that feeling you get— I like to hike and run in the mountains and sometimes on a hot day I'll jump into Fountain Lake, which is very cold and it's quite exhilarating. But also, there's sort of that feeling of panic for a second too. This is a very similar thing. So it definitely gave me an adrenaline rush that felt like something where you could really feel like, wow, something powerful must be happening here.

Brock: Yeah. But then what was about an hour later, that had completely worn off for you and you were basically back to normal?

The guy at the place that I went to claimed that it could super-oxygenate my blood, which is just ludicrous, a completely unscientific term.

Christie: Yeah. It wasn't very long lasting. And the sell here isn't— I haven't seen a lot of marketing around this, which is kind of too bad because I think one thing it does seem really effective for is giving you this adrenaline rush and it doesn't [get] marketed that way, but it's marketed to increase recovery to speed recovery. There's ideas that it's improving circulation and all of these other things. The guy at the place that I went to claimed that it could super-oxygenate my blood, which is just ludicrous, a completely unscientific term. So there's a lot of claims that are made about it that just didn't pan out. I went deep into the scientific literature, found that there really wasn't much evidence for the efficacy. There have been so many very egregious claims made about cryotherapy that the FDA actually put out some consumer warnings at one point just to let people know don't believe all the hype.

But there's also pretty good evidence. Now, one of the ideas behind cryotherapy is the same idea behind icing and ice baths and things like this. And the idea is that it's reducing inflammation and that this is going to speed recovery and aid healing. But it turns out that's not actually how it works. If you are looking for better recovery, if you're looking to help your body heal, inflammation is actually a necessary part of that process. And so you don't want to slow it. And what you're basically doing is slowing the travel of these necessary agents, inflammatory and immune system agents that are absolutely crucial in the healing process. So rather than expediting recovery, any kind of cooling, whether it's an ice bath or a cryotherapy actually seems to actually impair it and to hinder it and slow things down, which is exactly the opposite of what you want.

Brock: Okay, let's switch to the complete opposite and talk about infrared saunas.

Christie: Sure. So, I was really interested in the word infrared, which just seems to appear all over the recovery products. It's just such a scientific word and it really is fairly meaningless. It's just a description of a particular kind of heat.

Brock: It's just a spectrum of light.

Christie: Right. It's just part of the infrared spectrum. There's nothing special about it. Tom Brady has these infrared pajamas that, I mean basically they're just warm pajamas, but it sounds so much more scientific and high tech to say that they're infrared. And so what is an infrared sauna? It is basically just a sauna that from my experience it just feels a little bit cooler than a regular sauna. It isn't quite as hot.

Brock: Quite a bit cooler yeah. It feels just above room temperature most of the time.

Is there something extremely special about warmth that will aid recovery? Well, probably not too much.

Christie: Yeah. So sort of like a somewhat warm sauna, which can be pleasant. And personally I find heat to be a very pleasant and nice thing for recovery. And this goes back to the idea of if it's helping me feel relaxed and feel good, that's working and that's legitimate and we can say that's worthwhile. Is there something extremely special about warmth that will aid recovery? Well, probably not too much. The heat does increase circulation a little bit, but the fact of the matter is most athletes do not have problems with circulation. And so increase in circulation is going to have a pretty minimal affect.

And yeah, there are other ways to accomplish this. Like for instance, a warm down. Exercise is a really excellent way to increase your heart rate and your circulation. So circulation is just not the limiting factor here, but heat feels really good. And so if you are enjoying an infrared sauna and it feels good for you, go ahead and do it. I wouldn't recommend that someone go out and spend a lot of money on something like this if the only reason they're doing it is because they believe that infrared somehow has magical powers. Because I found in my research that it doesn't, unfortunately.

Brock: The sauna that I was using actually had settings, one was fat loss, and the other one was detox. It was really pushing this wellness sort of an aspect rather than just relaxation, which is really what I was using it for.

The idea that you're going to do something that will flush toxins or detoxify your body is just pseudoscience nonsense.

Christie: Yeah, it's so interesting. I mean a detox and flushing toxins and that sort of language is a real red flag. I mean there's really, we don't need to do those sorts of things. Our body has very effective ways of ridding itself of bad chemicals and things we don't need. The idea that you're going to do something that will flush toxins or detoxify your body is just pseudoscience nonsense. So I would steer clear of any claims that have those sorts of wordings in them.

Brock: Fair enough. Now, in terms of actually getting some relaxation, not that infrared saunas aren't relaxing, but I know you used a float tank and you seem to be a lot bigger fan of them than I was. I had the, the Homer Simpson response. In the book, you actually brought up the Simpsons episode where they go and do the float tanks and I was totally Homer. I was just laying there going “bored, bored, bored.” But you actually, you really enjoyed it.

Christie: I did. I did not expect that at all. I really expected to have the Homer Simpson experience and I was dreading it because I'm a little bit claustrophobic. I thought it would be really uncomfortable and tedious and all that. But what I found is I really enjoyed it. For me it felt like a really pleasant sort of forced relaxation or forced meditation, which I don't like what it says about me that I have to be forced to meditate. But it kind of felt like that long moment when you're falling asleep and it was very pleasant. It just was a really nice way for me to get into this sort of hyper state of relaxation and that was really nice. I enjoyed it. But I also recognize that it's not for everyone. And I think the takeaway here is not that floating is the magic bullet, but that every person should find some way and something for them that allows them to sort of get to this state, allows them to lie back and relax.

Massage is another really good way. Some people just meditate without the tank. These are things that you can do in a variety of ways. And I don't think that there's one correct way. The best way to do this is the way that works for you and the way that you enjoy, and that feels like something sustainable that you can continue doing. Because this rest and relaxation shouldn't be a special thing that you do only on occasions where you're feeling tired, but they should be things that are sort of part of your daily life. Every person should have some part of the day that's dedicated to relaxing where you're not feeling this urgency or this pressure to be productive and to get things done and to always be doing, doing, doing. There is some sort of beauty, but also health and wellbeing that comes from just sort of doing nothing, allowing yourself to just be.

Brock: What is it about us active individuals that we are just— and I hate to pick on us because I fall into this category as well because obviously I've done cryotherapy. I've done float tanks, I've tried infrared saunas, I've done the online blood tests, I've done all of this stuff, so I count myself among the suckers. I'm going to call us "suckers" for this type of stuff. Why do we go after all these supplements and these bars and these beverages when it really does sound like all we need to do is take a break?

We seem to be living at this time where we've been sold this idea that there is a perfect version of ourselves that's just out there waiting for us to attain.

Christie: Yeah, I think there's a couple of answers to that. One is that we seem to be living at this time where we've sort of been sold this idea that there is a perfect version of ourselves that's just out there waiting for us to attain. And if there's just one little weird thing we did, we could have it all. And that would make all of the difference. And so I think on the one hand it's this idea that science or these things that sound very scientific, that there's some sort of breakthrough that they can offer us. But the fact of the matter is our bodies are really sophisticated machines and they're actually quite good at making due under different environmental conditions. We're very good at adapting to different circumstances. And it turns out that the most important things that we need here are actually just the most basic and most fundamental.

It's things like sleep, eating nutritiously, reducing stress. But these are things that are sort of hard to master and even though on the one hand everyone knows them, and I've heard people say that my book is boring because it just says sleep more and things like this. But most people don't sleep enough and this is actually really important stuff. I think there's a tendency to think, I'd rather download an app or order this product than actually re-evaluate my priorities and rearrange my life a little bit. Because some of the things that we need to do actually may sound simple, but they're not.

Even something as fundamental as getting a good night's sleep every night and making that an important part of your day and not a special event or only on weekends sort of thing. That's not just a simple thing for a lot of people. It means rearranging some of the priorities in their lives. It may mean going to bed earlier than they ordinarily would. It may mean cutting out some other thing that's keeping you up late because if the choices is between another hour on Netflix or getting a good night's sleep, your body really needs the sleep, but sometimes our brains aren't so good at making those priorities.

Brock: Yeah. There is a spot in the book where I can't remember who you're talking to. I've got the quote here.

It's if you stick to the basics, you'll do fine. The problem is most people can't even do the basics. People are like, hey, what's the secret? I'm like, well, you train really hard. You sleep a lot. You eat well and you repeat it a lot.

Christie Aschwanden

Christie: Exactly, exactly. That's really fantastic advice and it's advice that no one wants to hear that. They want the magic bullet. They want the pill that they can take, they want the product that they could use. And I think the more that we can get away from that kind of sleeping, the better off we'll be in so many aspects of our life, not just for the recovery. We're sort of vulnerable to these claims in so many other arenas too.

Brock: Now, I wanted to ask you what the best way is to recover, but I'm pretty sure you've already covered that, so I'm not going to reiterate that. So instead, I'm going to ask you about when you were researching the book and you were going through all of this stuff. Was there one thing that really jumped out at you that you didn't expect? Was there an unexpected outcome or some sort of modality that surprised you in any way?

Christie: I think I was really surprised to find so little scientific evidence for the usefulness of massage.

I was really surprised to find so little scientific evidence for the usefulness of massage.

Brock: Yeah, that was a bummer. I found that to be the biggest bummer of the book.

Christie: Well, I think that's one way of looking at it. There's not a lot of good scientific evidence that massage is doing something tangible that we can measure in something in your blood or muscles or things like that. But I think one of the takeaways with this, it's not that massage is terrible and that it's just a scam. It's that massage may have benefits, but the benefits are not sort of the things that we've been sold on it. Massage isn't helping athletes feel better because it's flushing the lactic acid out of their muscles. First of all, we know that lactic acid isn't what makes you sore and probably by the time you're on the massage table, your body's already flushed that stuff out anyway. That lactic acid is pretty short lived in your muscles.

Brock: I think the most of the manufacturers of those things have now switched to the words "metabolic byproducts" rather than lactic acid.

I think that massage is helpful. It is good for recovery, but it's not because it's flushing something out of your muscles.

Christie: Which is another way of saying we're flushing out that gunk. That makes intuitive sense to us. I think that massage is helpful. It is good for recovery, but it's not because it's flushing something out of your muscles. It's because you're lying there and relaxing for an hour, and you're sort of checking in on your body and you're gaining this body awareness. That is a really important tool and a really important sense for athletes to develop. And so it's not helping you flush those byproducts or whatever, but it's just helping you feel good. Take time out of your day, you're lying there, you're not running around doing other things. You're not under stress. And I think sort of the potency of just that cannot be overstated. And I wished that people would appreciate that a little bit more. That you don't need the infrared, whatever it is to relax.

Christie: On the one hand, this stuff is actually really simple. I've had a lot of people write to me and say, wow, this has been really eyeopening for me. I'm so glad to hear that I can let go of all these anxieties that I had. I've been learning that a lot of people have become very stressed out about this stuff. And my book sort of gives them permission to stop fixating on this small stuff that doesn't really make a difference and isn't that important. And to really master the fundamentals, which again, is harder to do than it might seem, but it makes things so much easier because you're focusing on the big things that matter instead of chasing those tiny little gains that probably are just always going to be elusive.

Brock: Yeah. It's giving yourself permission once again to just relax occasionally. At the same time, you do have a through message throughout the book that even though things aren't scientifically proven and aren't actually doing anything in quotation marks, it doesn't mean you have to stop. You're not saying you're not poo-pooing these things and saying you're an idiot if you do this. You can still do it, but just realize what it's actually achieving.

Christie: Yeah I think that's right. And there are very few things that I looked into that were actually causing harm or seemed detrimental.

Brock: Yeah, I think supplements was really the only one that jumps to my mind that you actually said maybe avoid these because they could actually hurt you.

If there's one thing I hope people take away from the book, it's that there's just no good reason to take supplements

Christie: Oh, not maybe you should absolutely. If there's one thing I hope people take away from the book, it's that there's just no good reason to take supplements and there are a lot of really compelling reasons to avoid them. I recount in the book, multiple athletes who sat out at Olympic games and missed out on competition because they were serving time for doping offenses for things that they ingested through a supplement. And in some cases, even through supplements provided by their sponsors. So the idea that you can ascertain some that are better than others is just so many of the raw products are coming from the same places and at the end of the day there's just really no compelling evidence that any of this stuff is helpful anyway. So this is just another instance where, wow, you can actually stop worrying about that stuff. Stop wasting your money on these products that don't work and could actually harm you and focus that money and time and effort on something much more helpful.

Brock: Yeah. I guess to sum things up in the book you wrote:

The belief that there is some absolute perfect physiological state you can reach if only you do everything right, opens the way to dubious products that use the language and jargon of science to exploit our search for the ideal.

Christie Aschwanden

I think that really sums it up. Sort of why, I guess going back to my, why are we such suckers?

Well thank you so much for coming on the Get-Fit Guy podcast. I don't want to put any words in your mouth, but it seems to me like you're saying that we just need to relax more.

Christie: Exactly. Well put. Very well said.

Brock: Now, where can people find you and find your book if they're interested in finding out more info?

Christie: Sure. www.goodtogobook.com. You can find out all things about my book. My website is my name, christieaschwanden.com those are the best ways to find me. On Twitter I am @cragcrest. That's named after my very favorite trail run out here in Colorado.

Brock: Awesome. Thank you so much. I encourage everybody out there who's interested in this kind of stuff and does want to do a nice deep dive into all the science and pseudoscience and non-science and everything else around here to check out the book. I'll put links to all of the stuff we discussed in the show notes at getfitguy.quickanddirtytips.com. So thank you Christie.

Christie: Pleasure to be here.


Brock Armstrong is a certified AFLCA Group Fitness Leader with a designation in Portable Equipment, NCCP and CAC Triathlon Coach, and a TnT certified run coach. He is also on the board of advisors for the Primal Health Coach Institute and a guest faculty member of the Human Potential Institute. Do you have a fitness question? Leave a message on the Get-Fit Guy listener line. Your question could be featured on the show. Stay in the fitness loop! Listen and subscribe to the Get-Fit Guy show on Apple, Spotify, or wherever you get your podcasts.

Join the Fitness Conversation
Facebook | Twitter

All content here is for informational purposes only. This content does not replace the professional judgment of your own health provider. Please consult a licensed health professional for all individual questions and issues.

About the Author

Brock Armstrong Get-Fit Guy

Brock Armstrong was the host of the Get-Fit Guy podcast between 2017 and 2021. He is a certified AFLCA Group Fitness Leader with a designation in Portable Equipment, NCCP and CAC Triathlon Coach, and a TnT certified run coach. He is also on the board of advisors for the Primal Health Coach Institute and a guest faculty member of the Human Potential Institute.