Former teammate Mike Miller said James treats his body like an investment.
Miller said, via Bleacher Report:
"Where a lot of people don't do it, he puts a lot of money behind taking care of his body. A lot of people think it’s a big expense, but that big expense has allowed him to make a lot more money for a long period of time."
James has a whole team of people that work with him, from trainers to masseuses to chefs.
According to ESPN, when James was having back problems in 2015, he reached out to David Alexander, a trainer he worked with in Miami. Alexander pointed James to Donnie Raimon, a former Navy SEAL and an expert in biomechanics.
Raimon helped James work on his core strength, eventually fixing his back problems. James eventually hired Raimon full time and Raimon moved to Akron to be close to James.