Kristen Holmes: How to Optimize Your Sleep (Presented by WHOOP)

I had this when I was coaching for years, this is definitely kind of a theory, but we have been able to prove it on the WHOOP platform is that, what you’re doing from a training perspective does not correlate with next day recovery.

Welcome to the “BarBend Podcast,” where we talk to the smartest athletes, coaches, and minds from around the world of strength. I’m your host, David Thomas Tao, and this podcast is presented by barbend.com.

Today I’m talking to Kristen Holmes, the Vice President of Performance Science at WHOOP, which was kind enough to provide financial support for this episode.

Before joining WHOOP, Kristen was a three-time All-American and a two time Big Ten Athlete of the Year at the University of Iowa competing in both field hockey and basketball. She was a seven-year member of the USA National Field Hockey Team and also one of the most successful coaches in Ivy League history, having won 12 league titles in 13 seasons and a National Championship at Princeton University.

Kristen’s work uses data to better understand individual and team performance across tactical, sports, and medical verticals. It’s a lot.

In today’s episode, we dive deep on the role sleep plays in athletic performance, along with some amazing and actionable tips to get the most out of your rest, whether your goals are building strength, increasing mental focus, or just increasing quality of life in the long run.

Also, I want to take a second to say we’re incredibly thankful that you listen to this podcast, so if you haven’t already, be sure to leave a rating and a review of the BarBend Podcast in your app of choice. Now let’s get to it.

Today, I’m joined by a very special guest from our friends at WHOOP and that is Kristen Holmes. Kristen, thanks so much for joining us. I want to dive right into it.

Sleep and recovery, what is the main thing you think the general athletic or active population gets wrong with sleep?

Probably two things. Generally speaking, I think folks don’t necessarily give into or understand when their natural pressure for sleep actually is. That’s generally because we expose ourselves to a bunch of artificial light at night. We watch TV, we push past when we naturally feel sleepy.

We don’t necessarily work with all the cues that exist internally and externally — the environmental cues — that help us know when we need to go to sleep. I think a foundational level that’s probably one of the first things we want to try to stabilize or fix, is just that sleep/wake timing and make it as in-line with what your biological preference really is.

To do that you really have to think about your environment, you have to think about when you are having caffeine. You have to make sure that you’re not having naps during the day. I think too is important, like later on in the day, past two o’clock, that can really influence your pressure for sleep. Regulating sleep/wake time is probably one of the first things we need to get right if we want to really enhance and accelerate our recovery.

That’s, I think too, just getting that right has a cascade effect across our brain, our gut, our hormones. It affects all the other clocks in our body. I’d say that’s the number one thing to focus on, is getting your sleep/wake timing right.

One thing I know I struggle with, as an active person, and talking to, especially strength athletes, at BarBend we cover a lot of strength sports. We have listeners from all over the athletic realm, but a lot of lifters listen to this podcast. Lifters are really good at having really bad sleep schedules. It could be training at night, close to bedtime, it could be taking a ton of high-caffeine pre-workout around those evening training times.

Sleep hygiene is something I personally struggled with, I know it’s something a lot of people in the strength training community struggle with. What kind of structure do you personally recommend or practice around sleep hygiene and preparing yourself for sleep in the two/three hours before bedtime?

I think there’s a few things that are really important. One of the athletes that we work with, or have worked with in the past, he said this best, I think. He’s a professional basketball player, he says, “Preparing for sleep begins the moment you wake up.” It’s not necessarily just the two, three hours before bed, but it’s a lot of the behaviors throughout the day that accumulate to help you get an optimal nights rest or not.

I think there’s a few things to think about that are really core and then I can lead into maybe just a couple hours before bed. Working out later in the day, you are just going to feel more alert and awake, so the closer you workout to bed, it could be a little bit more difficult to come down. That’s certainly a consideration, as you mentioned. Caffeine after two o’clock is probably a bad idea.

It could stay in the system for up to seven, eight, nine hours, depending on how quickly you metabolize caffeine. That’s going to definitely prevent you from feeling sleepy. Caffeine timing’s really important. The other piece is protein consumption. Protein that’s difficult to digest can influence your ability to recover. It gets you into a parasympathetic state.

Which might sound good in the sense that…in order to digest food, you have to be in a parasympathetic state. That’s when digestion occurs. If you’re asking your system to digest huge amounts of protein, then you’re diverting resources that could otherwise go toward recovery and regeneration. That’s an important consideration too, the timing.

Being aware of how much protein you can actually metabolize and use is important to note. That’s going to vary depending on your weight, your size and what your goals are. That’s an important consideration. Rewinding even further, I would say really managing the stress/rest throughout the day is another huge influencer in terms of how well we’re able to sleep at night.

The more negative stress we accumulate, without moments of rest, the harder it is going to be to go to bed, to fall asleep. It will lead to a more fragmented type of sleep. Your sleep won’t be quite as consolidated. It will be more fragmented, which isn’t helpful for recovering, regeneration, muscle repair, all that.

 I want to talk through some of these factors one-by-one because you said a lot of really interesting things already. I want to just dive in. The first is something very near and dear to my heart — maybe too near and dear to my heart — which is caffeine consumption. Maybe the conventional wisdom is wrong. I’d always heard, “Well don’t drink caffeine after 5:00 PM.”

I don’t really know where that number came from. It’s something I heard. I’ve heard other people in active communities, people who are athletes, who are working out a lot, say, “After 5:00 PM, no caffeine.” You mentioned 2:00 PM. Let’s talk about how long caffeine tends to affect your ability to get rest, or even fall asleep, after you consume it.

Everyone is going to be a little bit different depending on how quickly you metabolize caffeine. I would say, rule-of-thumb, it can impact you for up to seven hours after you consume it. Again, body weight, all of that, is going to be important. How quickly you metabolize caffeine is another huge influence here.

Yeah.You mentioned naps as well. Having naps later in the day could impact your night’s rest. Naps are something that I know, in listening to the “WHOOP Podcast” which you’ve done an awesome job at, I guess guest-hosting?

Yeah.

You talk about naps can also be a way to super-charge your system and a way to really improve recovery. Let’s talk about nap-timing, especially when it comes to people who are very active, working out a lot and maybe using a nap to recover after training or something like that.

It’s an incredible recovery amplifier. There’s no question about it. Timing, again, is really important. I would say, generally, if you’re meeting your sleep need and you’re not training excessively, you should not feel sleepy during the day. That’s always a good litmus test. If you’re feeling sleepy during the day, you’re probably not getting enough sleep at night.

That’s something to revisit and rethink. If you’re doing a ton of heavy lifting, let’s say you’re doing a cardio session in the morning and then you’re doing a heavy weight session at night, a nap mid-day could be really, really helpful just to recharge, reset. I would say seven hours after you wake is when you’re going to start to feel a little sleepy if you maybe haven’t met your sleep need.

You’re in a training block where you’re doing pretty heavy volume and high intensity, a nap can be a massive recovery booster and energy booster. Generally speaking, you’re not going to want to go past 90 minutes because you’ll probably feel a little lethargic or groggy, 30 minutes is probably optimal.

Just paying attention to sleep debt generally, you don’t want to accumulate a lot of sleep debt because you never get back your lost biological sleep, like the nighttime sleep. That’s something to be aware of, too, is just keeping your sleep debt down.

Are you getting the sleep that you need at night? Then just being careful about naps in a sense that you don’t want it to interfere with your ability to get consolidated sleep at night.

What about folks who might have trouble napping but are looking to potentially incorporate it into their routine? You mentioned seven or eight hours after waking as a time when we might start to feel a little tired, if we’re not getting that optimal rest at night. That might be around the time when people are looking for a nap or thinking about a nap.

For people who might not be good nappers, they might just not fall asleep super quickly, and they might not be able to reach that restful state quickly. What are some tips or things that you’ve experienced when it comes to better preparing your body and getting better at just being able to grab those shorter intervals of rest?

A lot of the principles that apply for a good night’s sleep apply for napping as well. A cold, dark room is a great place to start. Just like you would at night, a good pre-bed routine involves maybe a hot shower.

That vasodilation, like in order to fall asleep, your core body temperature needs to drop. It sounds counterintuitive, but a hot shower pushes all the blood to the extremities. That process of vasodilation is actually what drops your core temperature, and it can help make you feel mellow and relaxed. I know that a shower in the middle of the day is not always possible.

Some mindful breathing, just breathing, relaxing, putting on music that’s super relaxing can be powerful just to get you in that mindset.

I think too, like after lunch is the time, especially if you’re taking in protein. Protein again is going to make you sleepy, and you want to put yourself in a parasympathetic state in order to optimally digest your protein. A nap after lunch is…you take a cue from the Europeans. There’s a reason why they do it. That’s probably an optimal time.

The other piece, too, if you’re considering napping, I know we love our morning coffee. If you’re doing two sessions a day, maybe skip the morning caffeine and then have some…if you are decent at falling asleep, you could have a little espresso before you lay down to sleep.

Then that espresso will wake you up in 30 minutes or so, and you wake up feeling pretty refreshed, so they call it the Napachino.

I was going to ask about the coffee nap. That’s something that I’ve heard it called before. I was going to ask about your thoughts on, is that a real thing?

Yeah. Dr. Amy Bender, she’s a Canadian scientist, does a lot of great work around this. Her advice is always, “If you’re not a good napper and you can’t fall asleep, it’s probably not worth it.” Because by the time you start to maybe…if it’s going to take you 20 minutes to fall asleep, then it’s not worth it because the caffeine’s going to kick in.

If you have the ability to conk out and fall asleep, then it can be a great strategy and definitely provide you a ton of energy when you wake up. Then counter-effect any of the inertia or the grogginess that could happen when you wake up after a nap.

I think just understanding what works for you and what doesn’t, and just making sure that you’re smart about how you go about it.

Let’s talk a little bit more about nutrient timing because you bring up the fact that protein takes a lot of energy to digest. I know a lot of athletes who swear off high-fat foods around training times.

It can give them digestive distress or be a little bit difficult to break down, so they’re going to go for a lot of simple carbohydrates, and a lot of easier-to-digest proteins, whey protein, obviously being a very popular one.

What are some other factors that you think are important when looking at nutrient timing and rest? Say you’re someone who likes that bedtime snack, for example. What are some foods, type of foods, or blends of macro and micronutrients that might basically make sleep easier, or at least not inhibit sleep as much as a heavy protein meal?

It’s a great question. Casein protein is awesome. It’s super easy to digest. I’m a huge fan of cottage cheese. Our tactical athletes on the platform, we do a little…we have some cool data around this. We had the guys do every night a pre-bed. They do a half a cup, a quarter cup of cottage cheese, a little bit of honey, raspberries, walnuts, and that was their pre-sleep cocktail.

What it has in there is the honey, which is awesome. It goes right to the liver and helps you feel satiated, and then you’ve got the casein protein, which again, easy to digest. You get a little hit of protein. It also makes you feel satiated, and it’s the same with the walnuts.

Walnuts and raspberries have a ton of serotonin, which is a precursor to melatonin, which is the chemical that helps us make us feel sleepy. That little prompt helps the release of…serotonin helps the release of melatonin, which is going to help you feel sleepy.

We saw sleep onset, so your ability to fall asleep, how long it takes you to fall asleep, we saw that decrease with this little intervention. We saw less fragmented sleep in the front end so guys were able to get into slow-wave sleep, were able to stay in deeper stages of sleep a little bit longer in the front end of their sleep. It’s a cool little study we did.

How did you come up with that particular food combination? It sounds like it works, and there’s a lot of interesting science behind it. It also sounds pretty delicious. I might try that before bed tonight.

Absolutely you should try it. It’s delicious. It’s just the perfect little natural sleep cocktail.

How big of a portion are we talking here?

A quarter cup, a half cup of cottage cheese, is plenty. I just think being really smart about the type of protein, close to bed, is important. Again, you want all the resources going toward recovery and regeneration. This is largely anecdotal, and I should say I am certainly not a nutritionist.

What we see on the platform, if you were to have a huge steak meal pretty close to bed, the next day HRV is going to be pretty low. What we theorize is that, again, you’re diverting a lot of the resources that would otherwise go to recovery and regeneration toward just having to digest this big, old piece of steak. Just being smart about the quality and the content and the timing is important.

What are you seeing on the WHOOP platform, in regard to recovery, when it comes to hydration around sleep? I tend to get thirsty at night, so I’ll try and drink a lot of water. At the same time, if you drink too much water before you go to bed, you’re not going to stay asleep, because you’re going to have to get up and go use the bathroom. Not to get too crass with it, but that’s what happens.

As athletes sometimes we want to feel like we’re always hydrated, because we hear that that improves recovery. What have you all learned regarding hydration around bedtime?

With just water generally it’s so, so important but how to think about hydration, is you should be drinking all day long. If we’re waiting to get a bulk of our water in prior to bed, to your point, it’s probably not a great strategy. You’re going to be waking up, which is going to be interrupting your sleep, which for some folks it’s hard to get back to sleep after they get up.

Drinking water throughout the day is really important. I would say getting up one time per night is not going to influence your sleep architecture in a meaningful way. Getting up more than once, you’re probably drinking too much water before bed. So I would try to time the water so you’re only getting up once per night.

One thing that we’ve been asked at BarBend and frankly, I didn’t have a good answer personally. Now fortunately, we work with a lot of really smart writers who do have good answers to things like this. It comes down to, “Look, I know I am about to come up on a period of life, it could be a week, it could be a few months.”

This is something we get a lot from young and new parents especially. Like, “I’m about to come up on a period where my sleep is going to be very interrupted. I think my sleep quality is going to go downhill. I might be just getting less sleep, and I know that’s going to happen because life happens.”

How might we, as athletes, look to be smarter about our training when we are coming up on those intervals? It could be due to travel. It could be due to new child, it could be due to any number of factors.

Yeah, I have a couple kids, I travel a lot. I’ve had hard training blocks, so I can relate to all those scenarios. I was a caregiver at one point when my grandma was sick. I had periods of my life personally, where sleep has been a challenge.

I think too, the professional athletes we work with, tons of travel. One of the great ways to think about it, is we have to be strategic. You have to plan. [laughs]

Anything you’re trying to be good at, anything you’re trying to fit in, you need to create a schedule around. Looking at your day and thinking about “OK, when is my time for sleep?”

This is one of our MLB teams with a platform. This is exactly how they think about, “OK, this is a schedule, how many hours of the day can we sleep, and when are those periods of time, and what’s optimal?” Strategically, that’s how to think about it, is map it out.

If you’re a new parent, working with your partner to make sure that you’re getting at least a block of five hours. That might be baby goes down at 9:00 PM, wakes up at one o’clock, two o’clock, nursed the baby, put the baby down, and then get that next block of sleep.

Thinking about it in those terms and try to getting — if you’re a new parent — getting your child on a schedule as best as possible is going to help.

Bottles [laughs] can be really helpful and the partner can feed, but having both parents exhausted, though, is not a great strategy. Working together to make sure that you’re dividing and conquering.

If one person is going to be up during the night, let’s say the mom is up during the night nursing, and then during the day she can pump, and then you can give her five, six hours where she gets some consolidated sleep. That can be an awesome strategy, particularly in the front-end of the day.

There’s a lot of ways to think about it, but getting a patch of time where you’re getting at least five hours in one block is important.

I want to talk about screen time now. It’s something that you, sorry screen time it almost sounded like I said scream time there for a second. It’s something you talked about a little earlier in our recording. Reducing screen time or screen time is something that keeps us from maybe recognizing our body’s natural signals that we are tired.

It’s something that we use as a crutch to push past like, “Oh, I’m tired but I’m on Tik Toc right now, so I’m going to avoid going to sleep.” Do you have a particular protocol that you personally like when it comes to reducing screen time?

That could be everything from having a cut off before bed like, this many minutes or hours before bed, no screens. All the way towards something like blue light blocking glasses, which I know is something that a lot of people use. I’m not personally sure how effective those are. I’m curious as to your thoughts on those kind of things.

Yeah, I wear blue light blocking glasses, dim the lights in my house. I definitely think about light it has a huge impact on our circadian rhythms. It’s an important cue to regulate sleep/wake timings. I definitely think about that really intentionally. As it relates to social media, I’m not on any platform at all. I guess LinkedIn, but I use that for work. Other than that, I don’t have Instagram, I have nothing. I don’t feel that pull, I guess, that a lot of folks do.

Getting out of that zone where all of a sudden it’s two hours later. It’s 11:30 and you’re scrolling through Instagram. I have eliminated that from my life with the intent of wanting to be really conscious of what I’m putting in front of my eyeballs. I’m giving myself the best chance to be as present and as rested as possible. That’s how I personally think about it.

For every person, you have to look inside and be a little bit introspective in terms of understanding what is this doing for me? Is this really upgrading my life? Is it not? Being able to make those kind of choices. Powering down an hour before you intend to sleep is probably a good…If I were to pinpoint, if you said, “Hey, give me a time.” I’d say, “An hour.”

Then you can start thinking more about bed and do some meditation. Really get yourself in a position where you’re actually in a position to sleep.

What kind of differences, when it comes to type of activity, are you seeing as far as the importance of sleep and recovery for athletes? Maybe an athlete is training for power output, like a weightlifter or a powerlifter, versus an athlete who might be a marathoner or a triathlete. Are they getting different things out of the sleep?

Depending on the answer there, are there different strategies or different approaches to sleep that those two different types of athletes might need to take?

You know it’s so interesting? I had this when I was coaching for years. This was definitely a theory, but we’ve been able to prove it on the WHOOP platform is that what you’re doing from a training perspective does not correlate with next day recovery. [laughs]

If you’re training for two, three hours a day, it’s the other 21, 22 hours of the day that are actually most influential on next day recovery. Sorry, I know this isn’t videoed, but I see your expression. I saw your response and that’s why I…

We can see each other’s faces, the listeners can’t. Just for context, listeners, Kristen said that and my face looked like one of those “huh” emojis. Just like, “Huh, OK.”

What’s interesting is not necessarily looking at, “Oh, I did a heavy weight session. I need to do XYZ.” It’s really about, “OK, what’s my goal for tomorrow in terms of my training? How do I need to think about my other 21 hours, or 22 hours of the day to help me position myself to do what I need to do tomorrow?”

Whatever my physiological intent is tomorrow, I need to think about my non-workout load and be strategic about that. Does that make sense? It’s less about the content of the training and more about the other hours of the day.

That has to do with sleep, but also, you mentioned earlier on in our recording, other non-training stressors that could accumulate over the course of the day.

Exactly, bouncing from one meeting to the next. If I know I have a hard workout tomorrow, I’m maybe a little bit more mindful about what I’m put in my body. I’m going to really focus on my hydration. I’m going to make sure I’m getting…All my macronutrients are in line to prep me for tomorrow’s workout.

Obviously, get my micronutrients in a way that I need, just trying to be as consistent across the board with that as possible. Being super mindful about how you’re thinking about recovery from a hydration, nutrition and rest/stress cycling is going to be core to the capacity you show up with tomorrow.

That’s absolutely fascinating. I’m really glad you framed it that way. That’s definitely going to change the way that I think about sleep and recovery in relation to training. When it comes to strength gains in particular, people who are strength-training, whether it’s to build muscle, build power output, build strength, walk us through what happens during sleep and during which phases of sleep.

We’ve actually worked with WHOOP on BarBend, with some really cool content about the different phases of sleep and how they impact strength gains. For the lifters who are listening, different phases of sleep, what roles do those have in recovery when it comes to strength and muscle regeneration?

A lot of your gains are going to happen in the front end of your sleep. That’s when you get a bulk of your slow-wave sleep. This is the only time frame that you release human growth hormone. If the front end of your sleep is fragmented, is not good, let’s say you have alcohol.

You’ll see the front end of your sleep, while you think you’re asleep just because you’re sedated from the alcohol, you’re actually not getting into the deeper stages in a meaningful way.

You’re not able to get return on all the work that you did that day because the only time you can regenerate and produce human growth hormone, which is going to build the muscle and help all the repair and the restoration, is during slow-wave sleep.

Getting into slow sleep is definitely a priority for athletes who are looking to build muscle, and gain strength, and just make fitness gains in general. That’s all the physical restoration. Again, making sure that you’re positioning yourself to optimize slow-wave sleep is critical.

You want to make sure that you’re not getting into a position…obviously, inflammation is important to a degree. You want to make sure that you’re not doing things like having NSAIDs, like Ibuprofen, for example, because that’s going to disrupt your slow-wave sleep, your ability to get into slow-wave sleep.

There’s a lot of literature to support this and it actually can decrease it up to 15 percent. Just being smart about what you’re putting in your body before bed and really taking that pre-bed routine seriously, so you can capitalize on all the work that you’ve done during that day to break down the muscles in order to build it back up at night.

All right. My final question is one I’m sure you and the team at WHOOP gets quite a bit. How much sleep do we need? Is there a concise answer to that?

Everyone needs something different. It’s based on how hard you’re working during the day, mentally and physically. Everyone is going to be a little bit different and a lot of it does depend on your environment.

If your environment is not conducive to sleep, you might need to spend longer in bed in order to get full regeneration, so the idea if you want to spend less time in bed, regulate your sleep/wake timing, and have an amazing environment that’s conducive for sleep.

Maybe the WHOOP cocktail with cottage cheese, walnuts, raspberries, and honey before bed too.

The WHOOP cocktail will go a long way. Yes. For sure.

[laughs] Kristen, thank you so much for taking the time to join us. I certainly learned quite a bit regarding sleep recovery. It’s really fascinating to hear it from someone who I say eats, sleeps, and breathes this, ha-ha, I guess pun intended, but who really has access to so much data when it comes to sleep and recovery, especially for athletes.

Where is the best place for folks to keep up to date with the work your team is doing in regard to recovery sleep and as it pertains to athletic performance?

Yeah. The Locker on whoop.com has any new validation or case studies will get posted there. Lots of educational content that goes into The Locker. Definitely on LinkedIn, I’ll post a ton of any new case studies, anything that I’m doing with particular teams that I’m able to talk about.

I’ll always post results, their outcomes. I definitely also push a ton of research that’s relevant to recovery, and building strength, and things like that. I try to push all the latest and greatest on that platform.

Whoop.com is awesome, The Locker, lots of great content there.

Awesome. Kristen, thanks so much for joining us and have a great rest of your…I mean, recording’s in the afternoon, but I feel like I need to say have a great evening, sleep well after this, so have a nice one. [laughs]

I appreciate that. Thank you. [laughs]