Nagekomi is a term familiar to most Japanese baseball fans. Even in the normally taxing Japanese baseball spring training menu, nagekomi, used in baseball to refer to marathon bullpen sessions, stands out as one of the most strenuous.

It’s also among the most perplexing in this day and age of increased focus on injuries to pitchers and how to prevent them. Even as many teams and doctors on the pro level carefully monitor how they use their pitchers, some Japanese hurlers still step in the bullpen and throw and throw and throw each spring.

Last week, Seibu Lions right-hander Ryoma Nogami threw 75 pitches before an intrasquad game, 23 during the game, and 304 more in the bullpen afterward, totalling 402 on the day. Elsewhere around Japan this spring, the Chiba Lotte Marines’ Hideaki Wakui has thrown 205 pitches during a bullpen session, while Orix Buffaloes duo Daiki Tomei and Tatsuya Sato have had sessions of 210 and 201, respectively.

Japanese baseball is known for long, hard spring practices. Still, there is an argument to be had about how much is too much. It’s hard to fathom that, even for a professional, throwing over 400 pitches in a single day isn’t a bit excessive.

If nothing else, it feels counterproductive, at time when so many are trying to solve the mysteries of the arm, to put these prized limbs under so much stress and strain. And for what return?

Part of the thinking is that by constant repetition, using good mechanics of course, you can train your body so that everything becomes second nature. Somewhere in there, through the pain, the fatigue and the mental strain, is the secret, the piece that completes the puzzle so to speak. It’s supposed to make the player tougher, more technically sound and smarter, an earned mixing of mind and body to achieve the desired physical nirvana.

Then again, Yu Darvish, one of the best Japanese pitchers in recent memory, eschewed the practice for the most part. So did Masahiro Tanaka, and the Hokkaido Nippon Ham Fighters, Darvish’s old team, don’t seem to be putting a heavy burden on right-hander Shohei Otani.

Which begs the question, can Seibu’s Nogami, to use him as an example, reach Darvish’s level simply by throwing enough pitches, regardless of everything else? Just how much can exhaustive repetition bridge the gap between natural talent and physical attributes? Is it really that easy — relatively speaking, of course? If so, why isn’t every pitcher in NPB, or in MLB even, doing it?

Building stamina takes many hours of training, but there is something to be said for quality over quantity. History, in NPB and MLB, is littered with players whose flames flickered out too soon due to dead arms, shoulder ailments or injuries to ligaments around the elbow, the current-day boogeyman, especially in the majors. While that all can’t be traced to overuse, there is some risk.

How hard to work pitchers is one of the biggest cultural differences between baseball in Japan and the U.S., and has been for a while. In his seminal 1989 book on Japanese baseball, “You Gotta Have Wa,” Robert Whiting included a telling quote from former San Francisco Giants and Kintetsu Buffaloes infielder Chris Arnold.

“I’ll tell you the big difference between Japan and the U.S,” Arnold begins. “In the U.S. we believe that a player has a certain amount of natural ability and with practice he reaches a certain peak point, but after that, no amount of practice will make him better — because after a certain point your ability reaches its limits. But the Japanese believe there is no peak point. They don’t recognize limits.”

Arnold’s view is perhaps a bit overly pessimistic, but the underlying meaning spotlights the thin line between working hard and physically working too much.

It would be premature to come to so simple of a conclusion as to say Japan is wrong or, conversely, that the West is right. Many Japanese pros have moved away from long throwing sessions, though they still throw far more often between starts than their MLB counterparts.

Still, 200-, 300- and 400-pitch bullpen sessions definitely leave room for a few questions.