The quarterback told The Associated Press that he'll give the Vikings an answer on whether he'll play by the July 30 start of training camp. Favre has been working out with the Oak Grove High School football team three days a week all summer, but added a Sunday workout this week.
"There's two weeks left and I'm doing everything I can," Favre said. "I was down here Sunday morning working out. I'm trying to get everything to where I feel 100 percent when I go in. I can't go in any less. When you're 39 years old, it's hard enough. But it's getting there."
The former Packers and Jets quarterback said surgery to repair a biceps tendon in his throwing arm was successful and that he has enough velocity to return to the NFL. He's just not sure whether that means he'll be able to compete for an entire season.
"I felt like going to New York last year that I still had it," Favre said. "I didn't know my arm was hurt at the time. So that's what I try to get across to people. I had that fixed, the surgery to fix that. So I'm trying to make sure that if I go back that that part is completely resolved."
It sure looked like it Wednesday morning, when a jovial Favre hit a variety of passes to high school and college wide receivers. He was crisp on short timing passes and was hitting receivers in the end zone from about 50 yards away. He attempted a few deep passes off bootlegs and usually hit his targets in stride.
Favre's spirals held true and he proved he still has plenty of zip when he tossed a deep pass to a college receiver who dropped by to work out. The pass split the receiver's hands and hit him in the face.
"He's a senior from Southeastern Louisiana, so I put a little more on it," Favre said with a smile.
Favre said if the arm strength wasn't there, he wouldn't be making a bid to return for his 19th season in the league.
"I don't think Minnesota would even consider it if I didn't have it," Favre said. "Second of all, I wouldn't even think about it if I didn't have it. Now, having it here and having in on the field on Sundays is two different things, I know that for a fact. I know what it takes to play on Sunday and I still believe I have that."
Favre said his hesitation is more about what those watching him practice might not see. He used a golfing analogy to explain his situation. What if, he asked, Tiger Woods came back and found he didn't have the same game?
"He goes out and hits a 2 iron and he thinks it will go the normal distance it has all his life, then all of a sudden it's 13 yards short, and he says, 'I don't know why that is because everything felt perfect,' so that's what I have to get through," Favre said.
"If you're throwing and it's a little off and you have a little pain, it's a little bit understandable. If there's no pain and there's no excuse, that's where you've got a problem. So I want to go out and have one of those days throwing and then have another where all of those throws you make, every warmup throw you make or just in general, feels perfect."
Favre was released by the Jets earlier this year, clearing the way for him to sign with any team willing to take him. Dr. James Andrews performed surgery May 22 to address the injured biceps tendon, which hampered Favre down the stretch last season.
The Vikings have remained mostly quiet on the topic in recent weeks, preferring to let Favre work through his rehabilitation from the surgery and make up his own mind.
At a fan forum in June, owner Zygi Wilf made it clear officials were receptive to Favre joining the team and the decision was Favre's to make.
"Right now, it's all up to Brett Favre in terms of where his future is at," Wilf told about 1,200 fans gathered at the State Theatre. "I'll just leave it at that."
Coach Brad Childress has had sporadic conversations with Favre throughout the summer.
"He's trying to make a push to get back," Childress said in June. "I just know this, he won't play unless he feels like he's able to play at the level that he's played over the course of the years. I know he's working hard."