Modern golfers look, practice and play differently than their predecessors, thanks to innovations in golf technology and a greater emphasis on strength training and fitness.

The adaptation of workout regimens is most noticeable in the likes of a Dustin Johnson, Adam Scott or Rory McIlroy, all of whom are big, strong athletes that happen to play golf. Watching Johnson pound 350-plus yard drives off the tee has become common place and seeing his feats of strength makes it impossible not to notice how different he looks than golfers of previous eras.

However, while they might not have the same body type, might not show off the physique with a Rory-like tight fitting shirt and might not hit it as far as those guys, you can be assured that most Tour golfers spend time in the gym or fitness center.

The Zach Johnson's of the world spend plenty of time working on their strength and flexibility in order to shorten the gap in power between them and the freak athletes that have begun taking over the sport. Fitness has become part of the job of a professional golfer, as their time is now split between the range, the short game area and the gym.

For players of past generations, there was a stigma attached to spending time in the gym rather than spending it at the range. That hasn't changed all that much when you hear older players talk about the current generation -- viewers of the Open Championship recently were treated to a brief rant from Johnny Miller on how McIlroy spends too much time in the gym and not enough working on his game -- but for the current players, the stigma is gone and it's an accepted necessity of the trade.

Tiger Woods helped changed that, as he was known for a strong workout regimen and became the face of golf fitness while ascending to the top of the rankings.

Randy Myers, the director of fitness at Sea Island Golf and the director of Nike Golf Performance, said that Woods came along right as golf technology evolved, which in turn, created even more advantages for guys that got stronger and faster.

"The ball got better, shafts got customized and because the technology got better, it forced the athlete to get better. Tiger was certainly one of the pre-eminent -- and still is -- guys from the workout standpoint, but Tiger was also one of these guys that was really flexible and thin, wiry guys. I just believe that he realized in order to be his best, he just needed to be stronger and maintain his flexibility. You see that, and then it mushrooms because it was suddenly cool for younger guys to be working out. Before it wasn't cool for younger guys [on Tour] to be working out, they were just trying to grind it out on the range."

Tiger Woods was long the face of golf fitness. USATSI

Golfers today aren't just jumping in the gym and cranking out random workouts. The advances in golf fitness have led to the creation of workouts tailored to golfers, and more specifically, each player gets workouts tailored to their golf game through a collaborative effort from their swing and strength coaches.

"Just like in football where you'd have a special teams coach, a position coach and strength coach, we do the same thing in golf," said Myers. "The player has a swing coach, and from there, we're able to determine through their ball flight if they need to create more speed. If they want to hit a ball a different way, we need to work on building their body and their frame a different way. We work heavily with the club-fitting aspect of it, because with Trackman today and Gears, which is the 3D motion capture simulator system, we're able to see swing efficiency. So if someone goes into an offseason program and wants to get stronger, but they lose club head speed, then we need to dial back the strength portion and go more back into the flexibility model. If someone's trying to get more flexible, but their swing style is tighter and they get loose, then we can go back and try to build more strength."

At Sea Island, the team has taken that collaborative approach to teaching and created an all-encompassing system called the Player Performance Index that assesses all aspects of a players' game including: fitness, short-game, putting and full swing to produce a handicap. The baseline of the handicap comes from the data from the Tour players they have that practice out of Sea Island, and that allows them to assess the average golfer's skills and physical attributes with empirical data.

"Twelve years ago, when we decided to get this team of staff together, we wanted to really address all aspects of the game and make people as good as we could make them at all levels," said Craig Allen, the manager of the Sea Island Golf Performance Center. "For years we've been doing that, but the question we'd always come back to is, 'yeah they come back and they say they're playing better and maybe their handicap gets better but how can we measure that? How can we measure how much we've been able to make them improve in certain areas of the game?' So, through all those conversations, we looked at it as, the NFL has a combine and they test players on their abilities -- how fast they can run, how far they can jump, all those things -- and then they grade them based on those tests.

"We put PPI together with a lot of research, the PGA Tour keeps all of their stats, and we came up with the short-game test based off of that and then we used the current Trackman Combine test, current SAM Putt Lab test and Randy came up with a fitness test based on data he gathered from the Tour players he works with. We put those tests together and the end result is a standardized test that we can equate a handicap to. There's no curve to the test, so you're really basing it against the very best in all those areas. The reason we don't want to curve it is, golf has a handicap. If you're a 14 handicap, you're a 14 handicap because you don't hit it as far as a Tour player. You don't hit it as close as a Tour player and you don't make as many putts as a Tour player."

The assessment of the PPI allows the instructors to understand where a player is, without having to rely on the player to tell them strengths and weaknesses, which, as Allen explained, tends to veer away from the truth.

"So many times you ask a golfer, 'hey what are your strengths and weaknesses?' And golfers are like fishermen, they catch a six-foot fish and really it was a three-foot fish," said Allen. "Golfers will say, 'Oh I drive it about 275 and hit 14 greens a round,' their reality is sometimes not really what's happening."

From there, the instructors can follow a player's progress by assessing them that same standardized test. With the fitness test included, instructors can better understand a player's limitations and restrictions with their body, which in turn, helps them build a swing tailored to their strengths that can help cover up their physical weaknesses.

"Knowing where those restrictions are really helps from a swing perspective and the instruction staff to cater towards that and find ways around that for them to swing," said Allen. "At the same time, it helps the swing staff to pinpoint issues they need to work on from a fitness standpoint."

The test can be used on golfers of all levels and ages, but where it's most useful is in determining whether a junior golfer has the attributes, especially physically, to be a Tour-level player in the future. An example Myers used of being able to tell a young player had Tour-level ability was the first time he saw Brooks Koepka as a freshman at Florida State without ever seeing him even swing a club.

"I'll tell you a Brooks Koepka story," said Myers. "I work with Florida State and I walk into Florida State's gym, and he's an 18-year-old freshman and he's on an incline dumbbell press doing 85 pound dumbbell presses for reps. 18 years old as a freshman in college! I get him off there, we go through the physical screening and he passes every test. This kid's doing as much as a defensive back and he's more functional than anyone on the team. I look at Trey Jones and say, 'This kid's going to be on Tour,' and I haven't even seen him hit a ball in college yet. If you're flexible and strong, and you have any kind of short game whatsoever, you've got a great shot at playing at the next level."

Brooks Koepka is one of the young athletes taking over the PGA Tour. USATSI

The trickle-down effect of the fitness boom in golf has moved from the professionals to the junior players, which has been part of the reason we see so many young players come in with the ability to handle the physical demands of the PGA Tour in their first years out there. College strength programs are tailoring workouts to golfers in a similar manner as Tour trainers, which is helping the athletes get stronger and maintain flexibility as they prepare to go pro.

Along with the added emphasis on workouts and fitness, the improvements in golf technology have significantly impacted the development of this generation of golf stars. There are constant improvements in club and ball technology, but the recent introduction of Trackman, a mobile data-gathering tool that allows players to see their ball flight, launch angle, spin rate, swing path and other empirical data in real time, has been a massive step forward for professional golfers -- and instructors.

Speaking with Allen, who works with pros like Davis Love III, Zach Johnson, Harris English, he explains that Trackman provides players with immediate data that they can get at any time -- step onto the range at any PGA Tour event and you'll see a Trackman set up behind most players -- which allows them to fine tune their game in a way players have never been able to do before.

"I think what the Tour players are doing is that they're now able to finely tune either their swing and/or their ball flight and maintain it," said Allen. "In other words, what you're seeing is guys are able to maintain high levels of performance for longer periods of time and you're seeing lesser drop-offs in their game and those drop-offs are for shorter periods of time.

"The reason being, they've got certain parameters that they try to maintain in their swing in terms of their path, attack angle, face-to-path relationship and things like that, and by being able to maintain them to a much tighter degree and get information instantaneously, they're much more precise in what they're doing. You're seeing better scores on the golf course and guys doing things we've never seen before. That is one of the tools that has helped them do that, no question. They're able to optimize ball flight and optimize their gapping to a level that's never been done, really."

There are some that think having that constant data is taking out the feel of the game and getting rid of the artistry of golf in favor of science. Allen thinks the opposite is the case, as players can now attach a data point to their feel, which in turn makes them more confident in competition.

"From a teaching standpoint, you bring up feel, Trackman allows them to equate a certain feel they have in the golf swing to a data-based result," said Allen. "So if their instructor wants them to achieve a certain number out of any one of those parameters, they can then equate that to, 'well if I make the swing like this, then I get that result.' And I think that's one part that gets lost on it.

"I think a lot of people get caught up in 'oh that's a lot of data, a lot of numbers,' well, yes. But the Tour players are really saying, 'OK, when I'm swinging shoulder-to-shoulder with my 54 degree it goes x-number of yards.' So, they're able to equate a feel with actual data and I think that's a big deal. No longer do you have to do it in competition. You can now build that trust and that confidence on the range using the technology and I think that's a big deal. They no longer get in competition and say, 'I think it's going to go that far.' They now know it's going to go that far."

For Tour players, the results speak for themselves, particularly with shorter shots. In 2006, only 14 players on the PGA Tour had an average proximity to the hole of less than 15 feet on approaches inside 100 yards. In 2016, there are 31 players with an average proximity of less than 15 feet on shots 100 yards and in. The combination of club tech, ball tech and data collection tools like Trackman have all played a role in making players more consistently dialed in with wedges and irons.

Jack Nicklaus recently remarked that the PGA Tour is stronger than its ever been, top-to-bottom. The influx of young talent into the PGA Tour -- and the ability of 40-plus-year-old golfers like Phil Mickelson and Henrik Stenson to maintain their strength and skill -- can be tied to the advancements in golf technology and the commitment to better training and fitness.

Some former players will continue to rail against the prevalence of Trackman and aggressive workouts in the weight room. Their concerns are understandable. If not used and adopted properly, the massive amounts of data available from using Trackman could confuse golfers more than help them, just as a golfer jumping in the gym without a plan could cause them to lose flexibility and power in their swing despite gaining muscle mass.

However, when used properly, the advancements on the tech and fitness sides can help tremendously, and the incredible achievements of golf's current generation has shown that. The Rory McIlroy's, Jason Day's and Jordan Spieth's of the world are using all of it to their advantage, and now we're seeing the fruits of that labor in the form of major championships and scoring records.

The new era of golf is that of the athlete and the scientist, combining feel with data to create better, more consistent players throughout the Tour.