"We've been stealing bases all year," he said. "This is what we do. We've emphasized it from Spring Training on. We're going to try and steal as many bases as we can and be aggressive."
The Astros lead the National League in bases stolen with 72, ranking second in the Majors behind Tampa Bay (75).
The team has signs meaning stop, free to go, or go, depending on the situation. Free to go means the runner can steal at will, while go means "go now."
Third baseman Ty Wigginton had a "go" sign with no outs in the ninth inning Friday after being hit by a pitch. He was caught at second base on a good throw from catcher Jose Molina.
"It was an ideal situation," Cooper said in defense of the call. "There was one ball and two strikes on the hitter [Michael Bourn], the [pitcher, Kyle Farnsworth,] had just thrown three straight fastballs. Surely there comes a breaking ball, surely on 1 and 2. It's a perfect time to run.
"It wasn't Wiggie, he had a real good jump. The guy just had a great throw. The [pitch] was up and away, and it was just like a pitchout. It was the perfect situation for him, and [Molina] throws pretty good. I would do that 100 times in a row.
Cooper said the steals have nothing to do with a recent slump by the middle of the Astros' lineup. His philosophy for running has always been to go whenever possible.
First baseman Lance Berkman stole second in the fourth inning after reaching on a fielder's choice, his 11th of the season and a career high.
But he was caught trying to steal third the next at-bat. Cooper said Berkman had the green light on a good opportunity to run, but he broke too soon.
"Guys are going to steal better when they get the green light as opposed to when I say, 'OK, you go,'" Cooper said. "You've got to get a good jump first. A guy can pick the situation and get a good jump, but he's on his own."
The Astros, who have been caught stealing 23 times this season, have a 75 percent success rate. Bourn leads the NL with 27 stolen bases and is third, behind Boston's Jacoby Ellsbury and Seattle's Ichiro Suzuki (29), in the Majors.
"I have no concern with stealing and running bases," Cooper said. "That's not why we lost. We lost because we didn't hit."