What if the key to a winning sports franchise isn't more and better practice but more and better sleep?

A growing body of evidence shows athletic performance of all shapes and sizes improves with even just a little bit of extra shut-eye, and yet the "sleep is for the weak" attitude persists.

In some cases, that is. Slowly but surely, more and more collegiate and professional athletes and their coaches are realizing that a little extra sleep isn't a sign of weakness after all, but more like a predictor of strength.

And it's not just that getting enough sleep improves performance; getting too little sleep hurts, too. One study of 25 years of Monday night football games found that West Coast teams won 63 percent of the time over East Coast -- read, sleepier -- teams.

So far, baseball and football teams seem to be the biggest believers, but hockey isn't far behind. Earlier this year, the NHL began investigating the use of Ambien among players and also made a number of changes to league policies that allow the players more rest during the season, writes sleep specialist and HuffPost blogger Michael J. Breus.

Hopefully, more and more professional -- and amateur! -- athletes will soon reap the benefits of some additional sleep. But in the meantime, here are some of the well-rested athletes paving the way.

  • Boston Red Sox
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    Larry Lucchino, Red Sox president and CEO, recently told a Boston radio station that the team has installed a sleep room at Fenway Park -- and the players are making good use of it. Catcher David Ross, speaking on another radio show, said, "We do have some times every once in a while where it's nice to go in there and get a little hour or so rest -- a little nap."
  • Northwestern Wildcats
    Coach Pat Fitzgerald has prioritized sleep among his players since taking the helm in 2006, The New York Times reported. But this year is the first that focus has shifted beyond altering practice schedules and mandating nap time.

    This season, the Wildcats are wearing on-body devices that track and analyze the quality and quantity of their sleep, according to the Chicago Tribune.

    "We made it a performance aspect they can use as a tool to prepare," Fitzgerald told the paper. "Anything we can do to maximize performance on the field and in the classroom is a positive thing."
  • New York Jets
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    In 2012, coach Rex Ryan enlisted a sleep specialist to help his New York Jets, hoping to capitalize on shut-eye's performance-enhancing capabilities. "If we can gain a little advantage, then we're going to look for it," Ryan told ESPN.

    Practices and meetings were rescheduled to better accommodate the players' sleep -- and they noticed the difference. "They're trying to help us in any way they can so we can perform at a high level," right tackle Austin Howard told ESPN. "It's absolutely a smart move."
  • Baltimore Ravens
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    The Ravens, too, looked to sleep for an extra edge. "We're turning over every stone, looking at everything in our program, to find any way to get better," head coach John Harbaugh said in a statement last year.

    The team's medical staff examined sleep patterns and suggested changes like moving weekday practices from 8:15 a.m. to 9 a.m. and learning how to most effectively handle jet lag when traveling to play West Coast teams.
  • Oakland Athletics & Detroit Tigers
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    Although these two teams are currently pitted against each other in the ALDS, they're on the same page about one thing: Both elected to take a day off after flying from Oakland to Detroit for Game 3 to help the players get some extra rest, MLB.com reported.

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  • ...Increase Stroke Risk

    Even without the typical risk factors, like being overweight or having a family history, short sleep can up your risk for stroke, according to 2012 research. Adults who regularly slept fewer than six hours a night had <a href="http://www.huffingtonpost.com/2012/06/11/sleep-stroke-risk_n_1586837.html">four times the risk of stroke symptoms</a>, HuffPost reported.

  • ...Lead To Obesity

    Too little sleep can spur some less-than-ideal food choices, including <a href="http://www.huffingtonpost.com/2013/02/25/sleep-portion-sizes-deprivation-food-calories_n_2735497.html">serving yourself larger portions</a>, and a hankering for junk food, thanks to some complicated hormonal changes that occur when you don't get sufficient shuteye. It seems that six hours of sleep or less <a href="http://www.huffingtonpost.com/2012/10/26/sleep-deprivation-obesity-leptin-ghrelin-insulin_n_2007043.html">bumps up production of the hunger hormone ghrelin</a> and limits leptin, which helps you balance your food intake, according to a 2012 review of 18 studies of sleep and appetite.

  • ...Up Diabetes Risk

    A pair of small studies from 2012 examined the link between poor sleep and insulin resistance, a telltale risk factor for diabetes. One found that among healthy teenagers, the <a href="http://www.huffingtonpost.com/2012/10/03/sleep-insulin-resistance-teens_n_1929374.html">shortest sleepers had the highest insulin resistance</a>, meaning the body is <a href="http://diabetes.niddk.nih.gov/dm/pubs/insulinresistance/#resistance">not using insulin effectively</a>, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The second study examined fat cells, in particular, and found that cutting back on sleep <a href="http://annals.org/article.aspx?articleid=1379773">increased insulin resistance in these cells</a>, even when <a href="http://news.health.com/2012/10/15/sleep-deprivation-insulin-resistance/">diet and calorie intake were restricted</a>, Health.com reported.

  • ...Fuel Memory Loss

    You probably know that on the days when you are most tired, you're forgetful and unfocused -- but sleep deprivation can lead to <a href="http://www.sciencedaily.com/releases/2013/01/130127134212.htm"><em>permanent</em> cognitive issues</a>. The less we sleep, the less we benefit from the memory-storing properties of sleep. But additionally, a lack of sleep can cause <a href="http://www.huffingtonpost.com/2013/01/28/sleep-deprivation-memory-loss_n_2566999.html">"brain deterioration,"</a> according to a 2013 study, which may at least in part explain memory loss in seniors.

  • ...Damage Bones

    At least in rats, long-term <a href="http://ebm.rsmjournals.com/content/237/9/1101.full">sleep deprivation seems to contribute to osteoporosis</a>, according to a 2012 study. Researchers found <a href="http://www.huffingtonpost.com/2012/09/26/sleep-deprivation-bones-marrow_n_1898610.html">changes to bone mineral density and bone marrow</a> in the rodents when they were deprived of shuteye over a period of 72 days. "If true in humans, and I expect that it may be, this work will have great impact on our understanding of <a href="http://www.eurekalert.org/pub_releases/2012-09/sfeb-los_1091812.php">the impact of sleep deprivation on osteoporosis</a> and inability to repair bone damage as we age," Steven R. Goodman, Ph.D., editor-in-chief of Experimental Biology and Medicine, said in a statement.

  • ...Increase Cancer Risk

    A small (but growing) body of research suggests that short and poor sleep can up risk for certain types of cancer. A 2010 study found that among 1,240 people screened for colorectal cancer, the 338 who were diagnosed were <a href="http://onlinelibrary.wiley.com/doi/10.1002/cncr.25507/abstract">more likely to average fewer than six hours of sleep</a> a night. Even after controlling for more traditional risk factors, polyps were more common in people who slept less, according to the study. Getting just six hours of sleep a night has also been linked to an <a href="http://www.huffingtonpost.com/2012/09/06/sleep-breast-cancer-aggressive-deprivation_n_1854658.html">increase of recurrence in breast cancer patients</a>. The study's author has pointed to more and better sleep as a possible pathway of reducing risk and recurrence.

  • ...Hurt Your Heart

    The stress and strain of too little sleep can cause the body to produce more of the chemicals and hormones that can lead to heart disease, according to 2011 research. The study found that people who slept for six hours or less each night and have problems staying asleep had a 48 percent <a href="http://www.sciencedaily.com/releases/2011/02/110208091426.htm">higher risk of developing or dying from heart disease</a>.

  • ...Kill You

    It's not just heart problems that can lead to sleep-deprivation-related death. In fact, <a href="http://healthland.time.com/2010/09/02/lack-of-sleep-can-cause-depression-weight-gain-and-even-death/">short sleepers seem to die younger</a> of any cause than people who sleep about 6.5 to 7.5 hours a night, TIME reported. A 2010 study examined the impact of short sleep on mortality and found that <a href="http://www.journalsleep.org/ViewAbstract.aspx?pid=27894">men who slept for less than six hours of sleep a night were four times more likely</a> to die over a 14-year period. The study's authors called this link "a risk that has been underestimated."

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