On July 17, 1945, Swedish sprinter Gunder Hägg set a world record with a time of 4 minutes 1.4 seconds in the mile run. The accomplishment was a 0.2-second improvement upon the time of fellow Swede Arne Andersson, set almost one year to the day prior and was nearly five-seconds faster than the world record time of 4:06.2 Hägg had previously set in 1942. 

At the time of Hägg’s 1945 record, many believed it was only a matter of time before someone broke the four-minute mark, an achievement once believed to be physically impossible. But for nine straight years, 4:01.4 stood as the record in the mile, marking the longest period of time that the record had gone unbroken since American John Paul Jones’ 4:15.4 mile in 1911 broke British runner Thomas Conneff’s 4:15.6 time set in 1895.

Many in the racing community began to wonder if the four-minute mile was a physical barrier simply unbreakable by human beings. Some in the scientific and medical communities championed that belief as well, noting that if the record were ever to be broken it would likely be on a day with absolutely perfect conditions—no wind, mild temperatures with low humidity, and a dry, hard clay track on which to run.

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On May 6, 1954, Englishman Roger Bannister stepped onto the Iffley Road Track in Oxford, England as 15 mile-per-hour winds whipped over dirt still moist with rain from the night before. Within a few minutes—well, 3:59.4 to be exact—the 25-year-old had broken Hägg’s record by a full two seconds, blasting through the four-minute mark and changing the world of running forever. 

Bannister is considered by many to be one of the greatest athletes to ever live. But beyond his obvious physical gifts, he was revolutionary in his approach to running, perfecting techniques—particularly alternating between prolonged periods of rest and of grueling training—that were untested then, but have now become common practice for runners today. 

Bannister, a full-time medical student at the time he broke the record, developed his methods through trial and error, and based many of his decisions on gut instinct alone. But today, athletes have a seemingly unlimited amount of information at their disposal, and as a result of modern technology and advanced training practices the record for the mile stands at a blazing 3:43.13 today.

Something that was largely lost on the athletes of the last century was the fact that what worked for one person wasn’t necessarily what was going to work for another. That realization was what helped Bannister break the four-minute mark, as he opted not to run at all for nearly a week leading up to the day of the race while his opponents continued to train vigorously.

Recent technological advancements have made it easier for athletes to train more effectively and more safely. This is especially true when we talk about wearables, which have become incredibly powerful and increasingly affordable in recent years, opening up a world of possibilities for professionals and amateurs alike.

For more casual athletes, wearables are a great way of planning and tracking physical activity, and, according to the Consumer Electronics Association, they’re one of the most powerful motivating tools available. By providing a log of distance traveled, calories burned, and average heart rate, these devices can take more overarching fitness goals and break them down into digestible portions, allowing users to experience the satisfaction of small, daily victories en route to a larger objective. And it pays off: In a 2014 study, the CEA found that wearable users are 85 percent more likely to achieve their fitness goals than non-users.  

Basic wearables can measure physical exertion, track heart rate, and calculate calories burned, but in recent years they’ve become far more advanced, prompting professional athletes and teams to use them in their training.

Image via USA TODAY Sports/Kyle Terada

It shouldn’t come as a surprise that the Golden State Warriors, situated just north of Silicon Valley, are among the biggest users of technology in pro sports. During practices, the reigning NBA champions outfit each player with a high-tech device situated in a small pocket and positioned on the back of each undershirt. The devices use GPS and an accelerometer to not only track movement on the court but also the force players are putting on their joints, allowing team trainers to better prevent injuries. And some of the players have decided to improve their own workouts using other high-tech products. 

Warriors point guard Stephen Curry uses specialized glasses that rapidly alternate between transparency and opacity to create a strobing effect. In much the way that baseball players will often take batting practice using a heavier bat in order to build up strength and increase swing speed, Curry uses the glasses to improve his reaction time, making his vision without the glasses feel almost supernatural by comparison. Fellow backcourt starter Klay Thompson, who finished second only to Curry in made three-pointers last season, uses a pair of devices that attach to both his wrist and the rim to track shooting efficiency during workouts. And 2015 Finals MVP Andre Iguodala uses a wearable device at night to track the quality and duration of his sleep.

Image via USA TODAY Sports/Kyle Terada

But being a great athlete is about more than just an amalgam of one’s physical gifts and practiced skills. There’s a huge mental component to any sport, especially when it comes to team athletics, that can’t be overlooked. This is an area where technology is quickly catching up to the demand of the marketplace, and pro teams are taking notice in pursuit of an edge over their rivals.

At least a half-dozen NFL clubs are currently utilizing virtual reality technology in their training, using headsets to put quarterbacks in fully immersive, game-like atmospheres. Using this technology, coaches can draw up plays and then test them against different defensive schemes, gauging the reaction time of players wearing the devices in real time. With league rules limiting the amount of time players can spend on the practice field each week, virtual reality could be a way for teams to get their players extra reps without risking their health.

Image via USA TODAY Sports/Jennifer Buchanan

The question at hand with all sports technology is simple: Can it make athletes better? Like anything else, technology alone won’t be enough to accomplish that goal, but it does give athletes the tools to remain motivated, better hone their skills, and stay healthy. When we’re training smarter, we’re training better, and that’s what becoming a great athlete is all about.