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Any NFL player relies on his body to make a living. Many more athletes thus invest heavily on conditioning and recovery to stay in peak shape.

ESPN.com's Jeremy Fowler profiled the deep lengths some veterans take to prolong their careers. No case is more extreme than James Harrison, the 39-year-old Pittsburgh Steelers linebacker preparing for his 14th season.

According to Fowler, Harrison spends around $300,000 a year on acupuncture, massage therapy, chiropractors and cupping. Most of the cost stems from traveling across the country to see specialists.

"I don't need to do the checks and balances like that," Harrison said. "When it comes down to it, what I make versus what I spend, the payout is worth it based on how I feel."

Safety Mike Mitchell, Harrison's Steelers teammate and training partner, estimated a $200,000 annual bill on his body maintenance expenses. The 30-year-old has tested body tempering, which Fowler described as "basically foam rolling with about 120 pounds of metal."

"Instead of rolling on it, it rolls on you," Mitchell said. "If you had any knots in your leg and they start moving that thing around, it gets painful at times. But when you stand up, you're loose immediately. It just smashes [the tension] out."

While those go the extra mile, retired NFL players Barry Cofield and Ryan Harris labeled $50,000 a fair average on yearly recovery costs. Cofield, who played for 10 seasons with the New York Giants and Washington Redskins, expressed regret over not spending more.

"If I were to go back, I would invest even more," Cofield told Fowler. "I'd probably spend twice as much. I was very healthy the first eight years of my career. Toward the end, maybe more treatments would have helped."

Ryan Shazier, a 24-year-old linebacker, expressed a willingness to follow the lead of his veteran Steelers teammates.

"If you pay $100,000 and you make an extra $3 million playing, that's an easy decision," Shazier said.

In terms of career longevity, investing on player recovery is far smarter than spending on cars and mansions. The average NFL player is lucky to play beyond 30, so Harrison's success should especially persuade peers to redirect their earnings.

But maybe they can just find local specialists.