Science of nap time: Seeking an edge in the most basic of all human needs
This story appears in the April 13, 2015, issue of Sports Illustrated. Subscribe to the magazine here.
On the night of last Nov. 14, Mike Napoli found himself speeding through a major city on old-fashioned roller skates, wearing tiny jean shorts, a tight white T-shirt and a Walkman attached to large, outdated headphones. "I was weaving around cars, and I remember going by a hotel," says the Red Sox' first baseman. "I could see that there was an NBA team checking in, and then, next thing I knew, I was in a mall, doing flips, twirling around."
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To Boston fans familiar with Napoli's adventures in celebrating around the city after the 2013 World Series, that scene might not sound so surreal. But it was actually Napoli's first dream in a decade, at least the first that he remembers, and he has a Harvard physician named Leonard Kaban to thank for the experience. Ten days earlier Dr. Kaban, Chief of Oral and Maxillofacial Surgery at Massachusetts General Hospital, had used a small power saw to cut and then reconfigure Napoli's chin, jaw and sinuses in a seven-hour procedure called maxillomandibular advancement. The goal was to allow the 33-year-old slugger, who had suffered from severe sleep apnea since his early 20s, to breathe more easily at night. "I used to wake up 50 or a hundred times a night," Napoli says. "Now I'm actually sleeping. I'm not tired all the time."
In the scientific quest to maximize athletic performance, as teams scrape for every win, Napoli is on the frontier of a burgeoning area of study: sleep. A number of major league teams, including the Giants, Rays, Rockies, Pirates and Indians, have consulted sleep experts in an attempt to fight fatigue and to exploit the so-called "circadian advantage." The man who coined that term, Dr. Christopher Winter, Medical Director of Charlottesville Neurology and Sleep Medicine in Virginia, was the lead author of a large 2009 study that examined how time-zone changes affect outcomes in major league baseball. His group recorded how frequently each team crossed a time zone over 10 seasons and discovered that if a team has to cross a time zone to play a game, it is at a slight disadvantage over and above a visiting team that does not deal with a time change; a team that crosses three time zones has just a 40% chance of victory. Winter, who is board certified in both neurology and sleep medicine, attributes this to a disruption in circadian rhythms—the body's sleep/wake cycle, which is synchronized to cues in the environment like light and temperature as well as the hormone melatonin.
Perhaps no team feels this more acutely than the Rockies, one of only two teams in the Mountain time zone. Says outfielder Michael Cuddyer, who joined the Mets this winter after three seasons with Colorado, "Every time you got on a plane, you were switching time zones ... you never felt like you were on the same clock." To combat the circadian disruption, Cuddyer attempted to trick his body's internal clock: "No matter where I was, 9 a.m. was 9 a.m. If I'm on the East Coast, and I'm used to getting up in Denver at nine, well now I've got to get up at 11. But it was hard. I don't know if it worked or not."
The Rockies are aware of their circadian disadvantage and try to minimize it by carefully selecting travel days. "If we had a home game, and then an off-day, and then a road city," Cuddyer says, "we would travel after that home game and spend the whole off-day in the road city. Most teams would leave on the off-day." Greg Feasal, Executive VP and Chief Operating Officer of the Rockies, says their consultation with sleep experts prompted the club to push back Sunday home games to 2 p.m. to give players more rest. Cuddyer says this arrangement helped, but he, like many players, was often dragging by midseason.
"Our research shows that sleepy players don't tend to stay in major league baseball as long as well-rested players," Dr. Winter says. "You need sleep to do all kinds of things: to produce growth hormone, to fight off infections and to heal." Winter works with a number of teams, including the Giants, who consulted him during last year's World Series. After San Francisco lost Game 2 in Kansas City, the team took his advice and did something it had rarely done before: stayed the night in Missouri instead of catching a late flight home. The next afternoon the team flew back to San Francisco; a week later they were Series champions.
"I was really surprised by how little education was flowing around these clubs," Dr. Winter says. "There was a lot of bad information out there." In the past, teams have paid thousands of dollars for 20-minute PowerPoint presentations and players were advised to use unusual, unproven sleep aids like magnetic bracelets or oxygen chambers. "Organizations were scammed," he says, "but sleep medicine is not a scam. It's about what sleep can do for you and what it can't."
We don’t really know why humans need sleep. From an evolutionary perspective, it doesn't make much sense: The unconscious state leaves us vulnerable, and sleep does nothing to replenish or propagate the species. But without it, we fall apart.
Sleep deprivation affects a baseball player—or any athlete—in a variety of ways, impairing reflexes, motivation, judgment, healing and attention. Chronic sleep deprivation can slow reaction times nearly tenfold, which is devastating for a hitter who has just .25 seconds to decide whether to swing at a Major League fastball. Dr. Scott Kutscher, a neurologist and sleep expert at Vanderbilt, has studied plate discipline—as measured by a hitter's tendency to swing at pitches outside of the strike zone—and argues that for many players, it becomes progressively worse over the course of a season. He believes this has to do with fatigue, which impairs judgment.
Kutscher and Winter are among the first generation of physicians investigating the impact of sleep deprivation on ballplayers, and their work reveals that there's not a one-size-fits-all solution for athletes. "It's more about understanding a player's physiology," Dr. Kutscher says. "Different people sleep differently." Experts can explain basic sleep hygiene to players, determine who is sleep deprived and identify a player with a sleep disorder that needs fixing. (Both Winter and Kutscher declined to discuss the specifics of the services they provide for professional baseball teams.) Interestingly, certain bodily functions may remain relatively impervious to fatigue. Some studies have found that muscle strength is not compromised by sleep deprivation. Things like the clean and jerk, squats and the 40-meter dash—tasks requiring short-term, high-power output—are largely unaffected by one or several nights of sleep loss. That's presumably why an exhausted Napoli could regularly hit a baseball 400 feet when he made good contact. Will better sleep help him do that more often? That's the hope for the Red Sox, for whom a couple of wins could make all the difference this season.
Last fall, Napoli was referred to Dr. Kaban because he was suffering from obstructive sleep apnea—his jaw muscles relaxed during sleep and the lower jaw and tongue fell back, causing his upper airway to collapse. He had all of the classic symptoms of a patient with a severe form of the disease: Constant fatigue, loud snoring, lack of dreams and apneic episodes—frequent moments when he'd simply stop breathing at night.
Obstructive sleep apnea places people at a higher risk for all kinds of other diseases, including diabetes, hypertension, heart disease, arrhythmias and stroke. Patients with severe, untreated obstructive sleep apnea—the kind Napoli was living with—have a two- to threefold higher risk of premature death than those without the condition.
"It started a long time ago," says Napoli, who began his big league career with the Angels in 2006 before being traded to the Rangers in '11. "I was still playing with the Angels and my mom came to visit me. I remember her saying, 'You've got some really weird sleeping patterns. You need to get it checked out.' But I was young, and I didn't do anything."
Because he ignored the problem, Napoli has spent much of his career feeling perpetually exhausted. "When I played in Texas," he says, "I was always tired. It got to the point where I would come out of games dizzy. I thought it was my blood sugar, and I tried to play through it." The unrelenting big league schedule—162 games in approximately 180 days—only exacerbated Napoli's' symptoms. He often woke up in hotel rooms short of breath and disoriented. "I wouldn't know where I was," he says. "I'd stop breathing and wake up and realize I was hallucinating."
Despite his chronic fatigue, Napoli, who signed with Boston before the 2013 season, hit 186 home runs over his first nine seasons; he only got tested for a sleep disorder because he repeatedly nodded off while driving. Napoli was diagnosed with severe obstructive sleep apnea—a condition that affects millions of Americans—and prescribed a host of treatments, including breathing machines, anti-anxiety medication and mouth guards. None of them worked.
When Napoli joined the Red Sox, a room inside Fenway Park was set aside for him to rest before games. "I usually took naps during batting practice," Napoli says, "because I was so tired every single day." Shortly after the 2014 season, he decided to do something drastic.
"We made an incision in Mike's gums above the teeth," Dr. Kaban says of the Nov. 4 operation. (Napoli gave his surgeon permission to speak about his medical condition.) "We dissected away the soft tissue to expose the upper jaw," Kaban continues, "then we used what's actually a rather delicate power saw to cut his upper jaw horizontally above the teeth and above the floor of the nose and sinuses." Once that incision was complete, Napoli's upper jaw was free from the skull base, and it was pushed forward about 12 millimeters and stabilized with bone plates and screws. Kaban and his team then went to work on Napoli's lower jaw, making an incision behind the molars. "We split it like a log," Kaban says, "and we slid the lower jaw forward about 12 millimeters." The procedure nearly doubled the size of Napoli's cramped airway.
Napoli spent the first night after the surgery in the Mass General intensive care unit. He went home a few days later with strict instructions not to eat or exercise. "It wasn't easy," Napoli says of the post-op experience. "I'm laying around my house, icing my face, taking pain meds. I couldn't eat—I went on liquid diet for six weeks. I lost 15 pounds." But after a few weeks he noticed that he was sleeping better, getting between seven and eight hours per night, and actually felt refreshed when he woke up in the morning. And of course he was starting to have evocative night visions. "The dreams were weird," he says. "Really weird."
This season batting practice might actually be a time for Napoli to swing, not sleep. Based on Dr. Kutscher's research, Napoli can expect to have better concentration, mood and reaction time with fewer headaches.
"I'm having another sleep study in a few weeks," Napoli says, "so the doctors can see exactly how well I'm sleeping." According to Dr. Kaban, approximately 90% of patients who have undergone maxillomandibular advancement report an improvement in sleep. But fewer of them—somewhere around 75%—actually score better several months after surgery during a formal sleep study (known as a polysomnogram). There is little consensus in the medical community regarding the role of facial surgery in patients with obstructive sleep apnea; surgical therapy is generally reserved for the most severe cases, and success isn't known until months after the operation.
Still, thus far it's hard to doubt that Mike Napoli is achieving a deeper form of sleep. That's why he's having such vivid dreams. His body is finally able to enter rapid eye movement (REM) sleep, which was previously impossible. He kept waking up before he could get there.
"He's worked hard this off-season," Dr. Kaban says, "and he's been through a lot. I hope Mike hits 30 home runs this year and drives in a hundred runs. And I hope he gets another World Series ring." If Napoli does put up those numbers and gets another ring, his surgeon might deserve one too.
Matt McCarthy is the author of the new book The Real Doctor Will See You Shortly.