12 Workout Warriors Poised for Big Things in the 2015 NFL Season

Top sports performance trainers reveal which NFL players put in the most hours training and preparing during the past off-season.

Football is one of the most physically demanding sports on Earth, so every athlete who plays in the NFL has to train hard during the off-season. But every year, there are a few guys who really get after it in their workouts—players who show up to the gym early, leave late, and don't go easy on a single rep. These are the guys to keep an eye on in the season ahead, the ones who are poised (and physically conditioned) to have a big year.

To get the inside scoop on who took their training especially seriously this year—and who might be ready for a standout 2015 season—we spoke with some of the country's top athletic performance trainers: Brian Abadie at Michael Johnson Performance, Brett Bartholomew at EXOS, Todd Durkin at Fitness Quest 10 and Travelle Gaines at Athletic Gaines. Here are some of the players they identified as true workout warriors during the past NFL off-season.

San Francisco 49ers QB Colin Kaepernick

Colin Kaepernick trains at EXOS in Arizona

The San Francisco 49ers underwent tremendous changes during the past year. Coach Jim Harbaugh, who led the team to one Super Bowl and three NFC Championship Games? Gone. Frank Gore, the stalwart runner who anchored the team's backfield for a decade? Buh-bye. Patrick Willis and Chris Borland? Held their retirement parties.

All of this is to say that much of the team's success or failure in the 2015 season will fall squarely on the shoulders of Kaepernick, their quarterback. Based on the work the signal caller put in while training at EXOS in Phoenix, Kaepernick is embracing the challenge.

"Colin personified a blue-collar work ethic along with tremendous accountability," says Brett Bartholomew, performance coach at EXOS. "He showed up to every session 20 minutes early or more to work on a variety of weak links and go through an extended warm-up. Colin understands the importance of the basics, and he was as steady and levelheaded as they come."

RELATED: Build Explosiveness With Colin Kaepernick's Workout

Pittsburgh Steelers WR Antonio Brown

He's gone to three straight Pro Bowls and he's considered one of the best wide receivers in the NFL, but Brown refuses to rest on his laurels. "He's the hardest working NFL athlete I've ever been around," says Travelle Gaines, owner of Athletic Gaines in Las Vegas. "The guy trains like a madman—twice a day, every day. His drive to be the best ever, to be considered the top wide receiver in the NFL, is crazy. He's had the same attitude since the first time I met him. He wants to outwork everybody. His balance is crazy. It's not even fair how good his balance is."

Want proof of Brown's balance skills? Check out his work on the BOSU ball in the video above. It'll help you understand how he keeps his body so under control on amazing plays like this.

RELATED: Antonio Brown Built His Ridiculous Footwork With Pilates

Detroit Lions RB Ameer Abdullah

Ameer Abdullah

He may be a rookie, but Abdullah approached training for his first NFL season like a polished vet.

"He showed up to day one of MJP's Pro Football Training Camp an hour and a half early," says Brian Abadie, Pro Athlete Coordinator for Michael Johnson Performance. "I asked him why he'd come so early, and he replied, 'This is the time I will have to be at the facility when I get to training camp, so I want to start waking up, eating and preparing my mind and body the way I will at camp.'"

Abadie was taken aback—and very impressed. "He was already preparing both mentally and physically to adjust to the NFL training camp life. I've never seen that before in my time here as a coach."

The former Nebraska Cornhuskers running back, Abdullah had a monster senior season in 2014, finishing with more than 1,600 rushing yards and 19 touchdowns; and he wants to build on that momentum heading into the pros. Abadie, who thinks the athlete is already ahead of the game, says, "He is the most dedicated, hardworking and mature individual I have ever been around for where he is in life."

The Philadelphia Eagles Offense

Mark Sanchez

The Eagles are another team enmeshed in change—to wit, the departures of last year's starting QB Nick Foles and team receptions leader Jeremy Maclin. They brought in Sam Bradford with the apparent intent to give the former St. Louis Ram the starting quarterback job, but it was Mark Sanchez who directed several offensive starters during the off-season.

"Sanchez hosted 'Nest West' out here in San Diego for a week over the summer," says Todd Durkin, founder of Fitness Quest 10. "I think we had 11 guys from their offense here. Mark is a great leader on that team, and he orchestrated a camp where we incorporated a ton of strength, speed, and conditioning along with a ton of fieldwork. The guys worked their butts off and got better."

Along with Sanchez, Durkin said several other Eagles players stood out in the group he trained during this off-season, including:

Darren Sproles

*Darren Sproles – According to Durkin, Sproles "is always a beast. He doesn't miss days. He goes hard all the time. He's a leader among the guys and all the guys look up to him and watch what he does. He doesn't take sets or reps off, ever."

Zach Ertz

*Zach Ertz – Durkin says of Ertz:  "This was his first year with me and what a talent! Great, coachable young man who works his butt off. He worked not only on strength, speed and field work, but also mindset. Zack has what it takes to be an All-Pro tight end." Durkin would know—he's trained many, including Saints QB Drew Brees and former Chargers and Jets standout RB LaDainian Tomlinson.

Jordan Matthews

*Jordan Matthews – "My goodness," Durkin says. "[Matthews] is strong, fast, athletic, and tough. I love his confidence, swag, and verbal leadership. He has the makings of what could be a great career." The Eagles WR also won praise from Bartholomew during his time at EXOS. "Talk about lightning in a bottle," Bartholomew says. "Jordan is another athlete who set himself apart by displaying the epitome of a 'growth mindset.' He took every opportunity he could to get better, and always wanted to learn the 'why' behind what we were doing. When you pair that kind of hunger and focus with athletic gifts like his, you are primed to plow the fields of success."

Buffalo Bills QB Tyrod Taylor

Tyrod Taylor

E.J. Manuel was thought to be the Bills' signal caller of the future when he was drafted two years ago, but things didn't go as planned. Buffalo brought in veteran Matt Cassell to start this season, and the competition got even hotter when former Ravens QB Tyrod Taylor leapt ahead of Manuel on the depth chart.

"Tyrod's calm, cool persona is one of the biggest assets to his success," Bartholomew says. "When most people talk about being a 'beast,' they reference the weight that they stack on the bar. That's part of it. But the real part that makes someone a 'beast' is their technique and tenacity that they bring to each set, each rep and each moment."

Bartholomew adds that Taylor's team-first mentality is another big asset. "He's a truly humble guy who not only looks to compete and challenge himself, but also to bring out the best in others."

Tampa Bay Buccaneers DT Gerald McCoy

Gerald McCoy

The Bucs' big man in the middle made a big splash in his time at Fitness Quest 10. "[McCoy] came out here for six weeks in the spring, and from 9 a.m. to 4 p.m. every day, he spent just about every minute training, doing Pilates, yoga, and stretch therapy," Durkin says. "Heck, he even jokingly put his picture on the 'staff wall,' as he's been known to answer phones at the front desk."

New Orleans Saints WR Brandin Cooks

Brandon Cooks

Shortly after the speedy receiver out of Oregon State was drafted by the Saints, he sought out Brees and began training with the QB under Durkin. Cooks's rookie season last year was going well—he had 53 catches, 550 yards and three touchdowns—before it was cut short by a hand injury. Now he's poised for a sophomore breakout, following a complete off-season spent with Brees and the rest of the crew at Fitness Quest 10.

"Cooksy is amazing," Durkin says. "He is a freak athlete and works his tail off. He watches what Sproles does and replicates his work ethic. In addition to all of our strength, speed and conditioning work, he spends extra time with Drew on the field going over every possible scenario."

Related: Path to the Pros 2014: Brandin Cooks

Buffalo Bills DB Ron Brooks

Brooks, a fourth-year cornerback out of LSU, had slowly but surely been taking on a bigger role with the Bills defense when new head coach Rex Ryan arrived this off-season and issued a new challenge: be ready to split time between corner and safety during the 2015 season. To prepare for the change, Brooks worked under Gaines's direction to bulk up without losing a step.

"Brooks gained about 10 pounds of lean muscle," Gaines said. "He's up to 195 pounds. Brooks worked out twice a day. I've never seen a guy work like that. He worked on his change of his change of direction and to get stronger."

New Orleans Saints RB Tim Hightower

Hightower has been out of the NFL for a few years, but he's attempting a comeback with the Saints. He had been a consistent performer in the Arizona Cardinals backfield during that team's emergence in the late 2000s, and he scored the touchdown that sent the team to Super Bowl XLIII. But he suffered a torn ACL in 2011 after being traded to the Washington, and was ultimately cut by that team in 2012. Since them he hadn't suited up for an NFL team until the Saints signed him in January.

Hightower joined Brees's training group under Durkin. "We did a ton of work," Durkin said. "Weights, field work, beach work… heck, we even went paddle boarding. Tim was always asking me, 'Todd, what do I need to do to get back to being great?' He put a lot of time into getting back in great shape and did all the little things to put himself in a situation to succeed. That's all you can ask. He's a special young man."

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