Democratic presidential candidate Bill Bradley released a statement from his physician Friday saying his recent problems with irregular heartbeat do not mean the condition is getting worse.
Bradley a few hours earlier blamed the problem on drinking too much cream soda on the campaign trail.
"The natural history of paroxysmal atrial fibrillation (irregular heart beat) includes sporadic increases in frequency of episodes which does not indicate any change in heart status," said Robert Heissenbuttel, Bradley's doctor.
"He has been advised to continue all normal activity without limitations," he added.
Aides to the former New Jersey senator handed out the brief printed statement at the Miller Time Bowl in Davenport where Bradley stopped in to search for votes among the beer-drinking, Friday night bowlers.
Bradley came dressed to bowl in a maroon sweater and open-necked shirt, and his campaign had planned to have him roll a few frames; but his schedule, which was slowed day-long by questions about his health, prevented that.
A day earlier, Bradley disclosed four new episodes of atrial fibrillation since December. But Friday he insisted voters should not be concerned and called his irregular heartbeat a nuisance which would have no impact on his ability to be president.
"I'd had Gatorade, orange soda and I went to cream soda. . . . Who knew that cream soda had caffeine in it?" Bradley told a news conference in Muscatine earlier in the day.
"Caffeine is one of the things that can set this off. It is possible that that happened. So I have curtailed my cream soda. It's only a hypothesis," Bradley said.
Bradley urged the media to put the issue into perspective in the few remaining days before Monday's party precinct caucuses in Iowa in which he will square off against fellow Democrat Vice President Gore in the first test of the election year.
His doctor also said in the statement that what triggers the problem is not known, and that his heart returns to a normal pattern "spontaneously" within hours.
The only symptom he feels, the physician added, is an irregularity of pulse.
Earlier, reporters asked Gore during a Des Moines hospital tour whether he was worried about Bradley after Thursday's disclosures.
"My understanding is that it's nothing serious," Gore said as he knelt with Mercy Medical Center asthma patient Shelby Claflin, 2, and her twin stuffed bunnies."
Looking to maintain momentum, Gore released two new television ads and a pair of radio spots Friday. The TV ads mention a panoply of issues -- Medicare, Medicaid, education, the environment. One makes a backhand swipe at Bradley, whose campaign has focused on a few important ideas. "I wouldn't just pay attention to one or two things," Gore says in his new ad.
On the GOP side, meanwhile, the contest between Texas Gov. George W. Bush and Arizona Sen. John McCain erupted Friday into an exchange of personal attacks, shattering the long-civil competition between the two leading candidates for the Republican presidential nomination.