Harbaugh said he isn't worried about burning out with the rigorous year-round schedule and pressures on an NFL coach.
"I don't foresee that, no," he said. "I'm just glad to be back at work, glad to be preparing for this ballgame."
Concern for Harbaugh's health reached his old Stanford campus, too.
"Pretty scary stuff, but it sounds like he's doing OK now," Cardinal coach David Shaw said. "And if I know Jim Harbaugh, it's going to take a lot more than that to stop Captain Comeback."
Running back Frank Gore certainly doesn't expect the excitable Harbaugh, who regularly becomes red-faced and angry at officials, to stray from his approach.
"He's going to be him," Gore said. "Coach is a tough guy."
And Harbaugh didn't seem to mind a little bit of good-natured razzing from his guys.
"We had to," defensive tackle Ricky Jean Francois said. "He's the guy you never think is going to get sick. He's good. We got him out there joking and laughing. He's in good spirits. It's good for him to be back on the field."
Notes: Harbaugh said QB Alex Smith's status for Monday is still unknown as he works back from a concussion, and he will be evaluated again by a neurologist. Backup Colin Kaepernick is getting a "little bit more work than normal," Harbaugh said. "Alex seems like things are progressing as it does." Smith practiced in a non-contact black jersey for the third straight day. ... RB Brandon Jacobs said his series of Twitter posts Thursday in which he referenced never working "in a place where you hate your boss so much, you should always be happy at work" were not directed at Harbaugh but rather toward the unstable work environment of his big brother, Michael. "I don't look at him as my boss. He's our coach and leader," Jacobs said. "I look at (GM) Trent Baalke as the boss." Jacobs — who hasn't played all season — also revealed he has long had an irregular heartbeat, and that the 49ers are aware of it. ... The NFL fined DT Ray McDonald $21,000 for a third-quarter hit on Rams QB Sam Bradford in Sunday's 24-24 tie.
AP Sports Writer Antonio Gonzalez contributed to this story from Stanford.
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