According to Adam Kilgore of the Washington Post, Harper won't even watch the 2013 MLB postseason, instead choosing to focus on bulking up for his 2014 campaign:
Bryce Harper will not be watching the playoffs, he said. He won’t even pay attention to the results. He cannot stomach postseason baseball when his team has been eliminated.
Harper, eventually, plans to lose himself in offseason weight lifting and to arrive at spring training "as big as a house."
ESPN lists Harper at 6'2" and 230 pounds. Harper isn't a small guy, but if all goes according to plan we'll see him much, much bigger next year.
Harper already has quite a bit of power, which he showed off during this year's Home Run Derby, in which he lost in the finals.
Now that he's going to bulk up a considerable amount, however, we could see him easily improve from 20 home runs to 30, or even 40.
Washington finished third in home runs in the NL this year, and a power surge for Harper could mean that the Nats lead the league next season. What's more, the Nats went 16-3 in games when Harper hit at least one home run.
Nationals fans are obviously on board with their young stud bulking up to improve his power, but they're hoping he does it the right way.
Dvorsky (@TheyGoToJared) September 30, 2013
Bryce Harper says he's "working to get big" during the off-season. Hope he doesn't start hanging out with A-Rod...— Travis Akers™ (@travisakers) September 30, 2013
However, with that power also comes a loss of mobility.
Harper's speed and fielding will likely take a hit if he gains more than 15 pounds, which appears to be his plan. He was successful on just 11 of his 15 attempts to steal a base this year, and a serious gain in weight would hold him back from swiping bases in 2014.
The Nationals aren't asking Harper to be the best defensive player in the game, however. They're asking him to lead the team at the plate, and bulking up will certainly help.
Harper getting bigger has the potential to have a huge impact on the team, and it's going to be interesting to see how he comes back next year.