The Indians will have Jason Kipnis on a very different offseason conditioning plan than the one he was on last winter. (This per Terry Pluto of the Cleveland Plain Dealer.) Last offseason Kipnis worked to add weight, in hopes that it would increase his power. Kipnis did in fact report to camp with more muscle on his frame, but the results were not at all what Kipnis, the team, or fans were hoping for.
Kipnis was the Tribe's best player in 2013, hitting .284/.366/.452, good for a wRC+ of 129, which was tied for 15th in the American League. He also stole 30 bases, tied for 7th in the league. He finished 11th in AL MVP voting. I suppose it's natural to always want more, but I'm not sure why Kipnis or the team would have felt compelled to try and make big changes to a player with that kind of production.
Whether last winter's workout routine actually led to his decline is impossible to know. He looked slower in the field to me, but his base running didn't really decline. Yes, his stolen bases fell from 30 to 23, but he reached base only ~75% as many times in 2014, so having ~75% as many stolen bases doesn't really seem to reflect a dip in his ability to run, just in his opportunities. His BABIP was way down, and it's possible that's in part because he was beating out fewer hits, but I'm hesitant to say he was really much slower this season.
Pluto mentions a decrease in his bat speed. I don't know if his bat speed was really worse this year than in the past. His strikeout rate actually declined, which I guess could be a result of lower bat speed, but it doesn't seem to me like that would be the relationship between the two.
If the added weight had a negative impact, hurting his defensive range (possibly be harming his flexibility) and making him more susceptible to injury seem like the most likely ill effects. It's possible this talk is just an attempt to spin a down season. We'll have to wait to see what Kipnis looks like when he shows up to camp in February to know if he really seems to have done things differently, and we'll have to wait longer than that to see if the on-field results are any different.
Getting the 2013 version of Kipnis back would be a major boost for the team though, so I'm going to hope there's something to this.