According to manager Matt Williams, Zimmerman also spent 15 minutes on a tread mill "at a brisk walk." The team hopes that Zimmerman can start jogging soon.
"For right now, he is making good progress. The pressure on the plantar fasciitis is being reduced and he is feeling better about it," Williams said.
Before going on the DL, Zimmerman was hitting .209 with five home runs, and his 34 RBIs ranked second on the team entering Tuesday.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the Time. He also can be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.