"I had a setback on Wednesday but I feel much better," Fuld said. "There's still some symptoms so I'm not really doing a heck of a lot yet. Just walking around and some slow walks is all I'm really doing right now."
Fuld added that this is his first documented concussion, and so it's hard to know what to expect. He's suffered from the usual symptoms such as sensitivity to light and sound, nausea and headaches.
"It's really frustrating," Fuld said. "We've all had our fair share of injuries but if you injure something, you can always make up for it with something else. Like if you injure your ankle, you can get on the arm bike or if it's your wrist, you can get on the bike or run around. But really the remedy here is to do nothing."
Twins manager Ron Gardenhire said Fuld will need to feel symptom-free for roughly four to five days before he'll be able to resume baseball activities.
"That's the process," Gardenhire said. "We just need to keep him to do that for four or five days now. The trainers say three but I say four or five. But once we let him do that, we'll make a decision and see if we can put him out there. But he has to be symptom-free before he starts running around on the field and doing baseball activities."
Fuld originally suffered his concussion on May 2 after running into the center-field wall at Target Field. He played in six games after the concussion before the symptoms began to worsen.
The Twins are looking into replacing their outfield walls to add new material to make them more cushioned, much like the walls at Chase Field in Phoenix. Twins owner Jim Pohlad called assistant general manager Rob Antony to discuss their options about improving the padding in the walls.
"We actually have talked about it," Antony said. "We're looking to see if there are any options of outfield walls we could install. I have to check with Major League Baseball to see if it's something we could do during the season or after the season."
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger. This story was not subject to the approval of Major League Baseball or its clubs.