It's incredibly difficult for many players to sustain high levels of production over an entire season, to the point that there's even been talk reducing the number of games in the season to relieve the strain it puts on players.
It also frequently comes up as one of the main difficulties players have in adjusting to the major leagues. Additionally, it comes up a subject among managers, wiyh effective managers often being ones take care to rest their players during the season.
The length and strain of the long season are ubiquitous subjects that get talked about all the time, to the point that they are practically defining features of baseball.
I mean the individual game isn't that taxing. Compare to the length of any other team sport - only basketball comes vaguely close at 80ish games. Anything physical is taxing if you do it a ridiculous number of times.
