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08/01/12 8:15 PM ET

Giambi ready to resume baseball activities

DENVER -- After prescribed rest and relaxation, Jason Giambi was back at Coors Field on Wednesday and ready to resume baseball activities.

The 41-year-old was placed on the 15-day disabled list July 21 with a viral syndrome.

"I had stomach aches, was kind of nauseated," Giambi said. "I was tired all the time, exhausted."

Giambi played through the malaise for about three weeks before he asked team doctors to check him out, figuring it was a combination of his age, the birth of he and his wife Kristian's first daughter, London, in November, and the 100-degree temperatures the Rockies were playing in.

"I started to notice my batting practices weren't very good, I wasn't able to go out to first base because I was so tired," Giambi said. "That's when I spoke up. We ran some tests and we went from there."

Giambi hit .100 in July (1-for-10), when he estimates he began feeling bad. The slugger took "a ton of antibiotics" and is hoping he's well enough to get back on the field soon.

"The big test will be how the stuff I do today goes," Giambi said. "I feel a lot better now. But first I've got to start. Like I said, I haven't really done much."

Helton, Cuddyer out of the lineup vs. Cards

DENVER -- The same flu-like symptoms that struck Dexter Fowler on Tuesday got to Todd Helton on Wednesday, making Helton unavailable for the Rockies' game against the Cardinals.

Fowler was unavailable on Tuesday night, but will be able to pinch-hit Wednesday if needed.

"I feel better, got a stomach ache and chills," Fowler said. "I feel a little weak."

Neither case is believed to be anything more than a stomach sickness, which should pass by the end of the week.

Also out for Wednesday's game is Michael Cuddyer, who's dealing with a sore right oblique.

"I'm very hopeful it's only a day and he'll be back in there [soon]," manager Jim Tracy said.

Tyler Colvin started in place of Helton at first base, and Andrew Brown started in right field for Cuddyer.

Worth noting

• Jorge De La Rosa threw a bullpen session on Wednesday. The left-hander is out for the season after undergoing Tommy John surgery last June.

• Carlos Gonzalez has a chance Wednesday night to tie Larry Walker for the longest home hitting streak in Rockies history. Walker hit in 30 consecutive games from May to July of 2002. Gonzalez notched his 29th straight game with a hit Tuesday night with an RBI single in the first inning.

Trey Scott is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.