Stanford’s H. Craig Heller Helps Sound Alarm on Athletes and Transmeridian Travel

Nothing puts the folly of collegiate conference realignment into sharper focus than Stanford University football players being forced to travel 2,831 miles due west across four time zones to play North Carolina State this fall as first-year members of the Atlantic Coast Conference. Future trips to Boston College will require the Cardinal, which joined the ACC along with Cal following the collapse of the Pac-12, to cover an additional 300 miles. These are the thoughts that keep Stanford biology professor H. Craig Heller up at night. So troubled was Heller by the recent wave of radical realignment that he summoned 25 colleagues from across the country to co-author an article on the impact of trans-meridional travel on athletes, published in the February edition of the Journal of Biological Rhythms. AB senior editor Paul Steinbach asked Heller, who served as president of the Sleep Research Society while the white paper was drafted, to detail the motivation behind his wake-up call.

What motivated you to produce this white paper?

It was triggered by the news announcement of UCLA and USC joining the Big Ten. That instantly set off alarm bells in my head that, my God, they are not taking into account the increased trans-meridional travel. Travel is bad enough, because it disrupts people’s schedules and interferes with their academic work — even with their training programs. But trans-meridional travel is a whole different beast because it leads to jet lag, and with multiple trips, chronic jet lag. Jet lag has very serious consequences for health and for performance — both physical performance and academic performance.

Why so many co-authors?

This is a small list. It could have been much, much bigger. It just was to give it the weight, to give it credibility. They also expressed concern and thought this was a really bad idea. And of course, at that time, we organized into a group to draft a white paper to call attention to the damage that increased trans-meridional travel can do to our student-athletes. And then, while we’re in this process, the problem got even worse with Stanford and Berkeley joining the Atlantic Coast Conference, which is even another time zone across. Plus, all of those schools on the other side, they reciprocate at one time or another by traveling. It’s not like going to school at the beginning of the quarter or going home for Christmas. It’s something that for many of these athletes would be repeated week after week.

What did you hope the paper would accomplish?

My original intent was to write an objection, but colleagues were a little bit wiser. They said, “Look, this is a done deal. There’s nothing we’re going to be able to do. The best we can do is to call attention to it and to offer mitigating strategies.”

I have to think that most athletics administrators don’t read the Journal of Biological Rhythms. How are you reaching your target audience?

Well, certainly, we’re hoping for more articles like yours. We’re hoping for blogs. And we’re just distributing it now. That is the official journal of the Society for Research on Biological Rhythms. The other possibility that we had access to immediately was Sleep, which is the journal of the Sleep Research Society. Sleep, unfortunately, has a policy that they do not forgo publication charges, open-access charges, and we had no money for this. We had no sources of several thousands of dollars. So, my colleagues from the other Journal said, “Oh, we’ll certainly publish it for free,” which they did. Now, some of my colleagues have criticized us for this and said, “No, this should be in a place with much more visibility, such as Science or Nature.” But we figured that it will spread. It will get out there. And it is open access, so anybody can obtain it. They don’t have to be members of the society or subscribers to the journal.

That said, how cognizant of sleep issues do you think the typical collegiate coach or athletics administrator is?

Practically zilch. That’s why one of the recommendations we have is for coaches and athletic trainers to call upon their colleagues who have this expertise within their own universities — to bring in scientists and physicians with expertise in sleep and circadian rhythms to help them introduce mitigating strategies into their programs.

Do most campuses have people like you on them?

Well, these are big areas of research, so for research universities, for the major universities, they all would have these areas represented. The Sleep Research Society puts on a conference every year, along with the American Academy of Sleep Medicine, and that conference routinely attracts 5,000 people — all physicians and scientists. If they have someone on their campus, use them. Otherwise, reach out.

Do you expect to hear from coaches or ADs who want to know more or seek your advice?

I hope so. At mid-process, we met with the NCAA and invited them to participate. We met with them at their headquarters and had a half-day discussion, and they were enthusiastic about it and actually are considering creating a program that would provide education for coaching staffs and so forth.

What is the minimum amount of sleep that, say, male athletes ages 18 to 24 should be experiencing to reach optimum performance mentally and physically?

Well, the best way to ask if someone is sleep deprived, or someone has not had enough sleep, is asking them whether they sleep in on the weekends. Someone who is sleep satiated, has had adequate sleep every night, they’re not going to sleep in on the weekend. So that is a very simple symptomatic measure of whether or not someone is sleep deprived. How much sleep someone needs varies enormously. For some college-level individuals, it can be nine hours a night is optimal for them — others, six hours or seven hours. We normally hear the average figure of eight hours of sleep, but that doesn’t pertain to everyone.

Is there a difference between males and females?

Not significantly. I’m not aware of any really definitive studies of difference between males and females. I’m sure there are people who have made claims, but the variability from individual to individual is greater than what you would expect from male/female.

Collegiate team travel schedules are almost guaranteed to put athletes at risk of chronic jet lag, right?

Absolutely. If you travel one time zone, it takes most individuals a day to re-adjust. Two time zones? Two days. Three time zones? Three days. Let’s say you’ve traveled three time zones, you’re there for at least two days, and then there is the problem of the overnight travel coming home, which is also very disruptive. But let’s just say everybody is feeling very generous, and we’ll give them three days. And if it’s baseball or tournament basketball, when they have multiple games, that’s highly likely. You go to your new location. You’re going to be jet lagged for three days. But after that three days, you’re pretty much synchronized with your new environment. But then you go home, and you have the same sequence of events in the return travel. If these travels are weekly, or biweekly, it just adds up. That’s why it’s chronic.

The paper says, “Chronic jet lag is more likely to lead to undesirable and even pathological results.” What is meant by pathological results?

Well, the simplest one is insomnia — so, lack of sleep even after you return home, or certainly in the new location. There are many, many papers in the medical literature that link chronic jet lag and high blood pressure, diabetes, a whole host of things. But there are also quite a few papers that are showing effects on academic performance of sleep deficits. A good night’s sleep is really important for health, and one of the worst things that can happen is to have your sleep disrupted and fragmented by jet lag.

Another sentence that stood out for me from the paper, “Feelings of anger, sadness and suicide ideations were three times higher in college athletes compared to their non-athlete peers, even when matched for gender and age.” That is stunning to me.

Yeah, it certainly is.

According to the paper, “Eastward travel requires more time to adjust than westward for most people. Thus, the aphorism east is least, west is best when it comes to getting over jet lag.” Why is that?

That has to do with the mechanism of the circadian system, the realignment of the circadian system. If you are out of sync with the real world, you can either phase advance or phase delay your rhythm. In other words, turn your clock ahead or turn your clock back. Now, the way you do that is by exposure to light in the morning, or the evening. If you’re exposed to light in the evening, when you normally shouldn’t see light, that phase delays your internal clock. If you see light in the early morning, when your internal clock is not expecting it, that phase advances your clock and helps you come into sync with local time. Now, the system is less sensitive to phase-advance stimuli than to phase delay. So, when you’re traveling from east to west, you are essentially going to be seeing light in the evening longer than you otherwise would. And that causes a phase delay and brings your clock into sync with the later time on the east coast. It’s just the biology of the clock, that you get bigger phase delays than you get phase advances for the same situation — exposure to light, morning or evening. Exposure to light in the morning phase advances, exposure to light in the evening phase delays, and phase delays are bigger than phase advances.

I would think that being the western-most member of a conference, as Stanford and Cal are going to be, would just be an inherent competitive disadvantage.

Yeah, it is. Sure. Absolutely. You see the difference between the new situation and the old. With the old situation — Pac-12 — you had a lot of travel, and travel alone is disruptive. But when it’s north-south travel, you don’t have the complication of jet lag. Now all of a sudden, the refocusing of alignments so that it’s more east-west than north-south is what generates the problem. Published papers show that the odds of winning change dramatically if you have undergone a situation that gives you jet lag.

Is there an advantage to continuous sleep versus interrupted sleep that incorporates naps to catch up to the desired number of total hours? Is one preferable to the other?

Oh, yes. First of all, naps are not bad. Naps can help. But they’re not the same as adequate nighttime sleep. In general, a nap does not include REM sleep, and therefore it’s not the same as nighttime sleep. Now, I say that, but I can’t answer the follow-up question: What is the function of REM that you’re missing? Because we don’t know that one, actually. We know lots of functions of non-REM sleep, but we don’t have any clear agreement or even any clear evidence supporting a particular function of REM sleep. But it is critical. Now, back to your original question of whether or not fragmented sleep is as good as continuous sleep, and the answer is no. But it also depends on the frequency of the fragmentation. The extreme example are people who have sleep apnea, and they may wake up 200 or 300 times a night. They don’t realize it. The next morning they complain, not about lack of sleep, they complain about daytime sleepiness. And they go to see the doctor because they are groggy during the day, and they have no idea they are sleeping poorly. One of the reasons why fragmented sleep is not as good as continuous sleep is that whenever you are aroused from sleep, whenever you wake up, it then takes you a period of time to get back into the deepest levels of non-REM sleep, the levels that provide the benefits. If you’re woken up like someone who has sleep apnea, every 10 or 15 minutes, that means you are getting much less deep non-REM sleep. You may be asleep the same amount of time, but it’s not the same quality sleep.

You say “deep non-REM sleep,” I always assumed REM sleep was the deepest.

No, actually REM sleep is closer to wakefulness than it is to non-REM sleep. That’s why you have your most vivid dreams in REM sleep. The cortex of your brain is active again, but your muscles are paralyzed so you can’t act out your dreams. But the non-REM sleep, also called slow-wave sleep, is when the EEG has big slow waves in it. And that’s due to the fact that large populations of neurons in your brain are firing at the same time, at a pulse rate of anywhere from one to four times per second. So that’s the deepest, and that’s the restorative sleep. So someone who has sleep apnea, they may have the same number of hours of total sleep, or close to the same number of hours, but the quality of the sleep is very different. And if you’re an athlete and you’re traveling, you’re never going to have the same quality sleep in your first night. This is called the first-night effect. The first night in any new environment is going to be disruptive, but if, in addition, your brain clock is telling you that you should be awake, it makes it even worse.

Let’s say I get eight hours of sleep. Ideally, what percentage of that eight hours is the deep, restorative sleep you’re talking about?

Roughly 80 percent of your sleep is non-REM and 20 percent is REM. But you get the deepest, non-REM sleep early in the night. The first half of the night might be 80 percent, 90 percent deep non-REM. And then in the second half of the night, you have more REM sleep, and your non-REM is not as deep. We’d classify non-REM as stage one, two, three. Stage one, when you go to sleep, you’re just sort of dozing off. Stage two is deep, but the cortex is not as synchronized as it is in stage three. In stage three, you have these big, big slow waves.

When you hear the NCAA, or collegiate conferences, or even individual athletic departments talk about making the mental wellness of student-athletes a priority, how does that jibe with regularly sending kids cross country to compete?

I’d like to give them the benefit of the doubt that they just don’t know. They don’t understand these connections. And that’s why I encourage better relationships between the medical and the research parts of their institutions and their athletic staff. I mean, they have all that expertise available, why not use it? But I went over a lot of the articles about the realignment of the conferences, and not a single one mentioned problems for the student-athletes.

How I learned of the defection of UCLA and USC to the Big Ten was in a June 2022 article by Pat Forde of Sports Illustrated. He wrote, “As an example, when Penn State travels all day on a Monday to play UCLA in basketball on a Tuesday and then flies home overnight, 60 percent of the academic week is trashed. Coursework will be harder to maintain. In-season fatigue will increase. Mental health consequently will suffer. All the buzzword off-field stuff administrators pretend to care about will be further jeopardized. Don’t believe them when they say otherwise.”

Oh, that’s wonderful. I hadn’t seen that.

He didn’t mention sleep specifically, but I think he was getting at that very thing.

That’s terrific. The one article I read that talked about deficits or problems that are incurred by this, mentioned the impact on the university in terms of travel costs. Nothing about the impact on the student, just on increased cost to travel.

When you learned of the defections of UCLA and USC, did you fear for the future of the Pac-12?

Oh, yeah. I did. But my immediate feelings were more for the students. I work with a lot of student-athletes, so I realize what stresses they’re under. To give them a lot of credit, they are the most organized and time-efficient students in the university.

Is that right?

They have to be, in order to accomplish what they’re doing. Why make things worse for them?

Before Stanford agreed to join the ACC, did anyone at the university seek your input as to what this might mean for Cardinal athletes?

No.

What do you recommend schools whose travel is going to encompass all four continental U.S. time zones do to mitigate sleep deprivation?

Well, one thing that they can do is pre-adaptation, but that’s not easy for college students. And of course, it depends on the local environment. If they have common housing for athletes, they can try to change the timing of “lights out.” But even if they can do it logistically, it’s not easy physiologically. What happens with young people, with adolescents and up until about 20, is they have a natural phase delay in their rhythms. You know, for little kids, come 8 o’clock at night, boom, they’re out. Even for middle school kids, not much problem going to sleep by 9 or 10. But after that, they cannot. Their rhythms have switched, have changed, have been phase altered, so that they can’t go to sleep earlier, and therefore, they can’t get awake earlier. So that’s why all over the country, there has been a national movement for school start times to change. It used to be you sent the big kids to school earliest and then the little kids later, and most states now appreciate the fact that the other way is preferable. You send the little kids to school early and then you send the big kids to school a little later. That phase change of circadian systems, it’s natural, it comes with adolescence, and it is a fact of nature. So even though you may tell someone and they agree that they should go to bed at 9 o’clock at night, it doesn’t mean they can sleep.

Can you envision athletic departments, in this era of coast-to-coast conferences, investing in a full-time sleep expert?

I think that’s possible. But you know, it’s part of the health program, so another way to think about it is educating your sports medicine staff in terms of sleep, so that they are aware of it, they’re conscious of the problems, and they can raise the issue regularly. One of the things that could be done with wearables now is we can actually keep track of the sleep and activity patterns of individual athletes. Then you get the problem of confidentiality with HIPPA regulations, but the point is that the data can be collected. And if the data can be accessed by authorized individuals, such as the team physicians, it would be possible to assess the needs of the individual students. Now, whether or not you can operationalize that in planning, travel and so forth for the whole team, that’s another question. But you could keep track of what the problems are due to travel.

Would you advocate for a greater investment in sleep-supporting infrastructure, such as dedicated nap rooms or sleep pods within an athletic complex, to help kids catch up in between classes?

Yes, I think there are a lot of things that could be done in the environment of students. As I said naps do help, so I wouldn’t want to poopoo that. And if indeed, students are able to take advantage of that, that would be great. The best time for a nap is early afternoon. So, if students can take an hour at that particular time of day, that’s when it would be easiest for them to fall asleep, and that would be good. I know some of the professional teams are actually using specialized beds. They are experimenting with ways to improve their athletes sleep by providing them with better beds, which actually record all the characteristics of your sleep. People are actually able to dial in temperature profiles on their bed to maximize their sleep. Normally, early in the evening, people want to be warmer, and then toward the early morning, they want to be cooler. There are beds now that have these temperature profiles, and you can sort of twiddle with it to get the profile that is best for you. And the feedback you have is the bed is also recording your movements, your non-REM sleep, supposedly your REM, but that’s not easy to document accurately.

Can you envision a scenario in which the health and performance of athletes become so compromised that a return to regionality becomes the clear choice in conference alignment, or is that horse out of the barn?

I think the horse is out of the barn. What happens when you have a change in practice and there is an obvious deficit, what you do is you try to compensate for the deficit and then you forget that prior to the deficit things were better. It’s just not human nature to go back. We very readily adjust or adapt to new situations, even if they are not optimal.