SANTA CLARA, Calif. — Frank Gore darts around the practice field these days like a man not burdened by the past. That's what a new offensive scheme is doing for the San Francisco 49ers' Pro Bowl running back.

Gore says he is loving every minute he spends in offensive coordinator Mike Martz's attack. After suffering as part of the NFL's worst offense during a very discouraging 2007 season, Gore has a whole new outlook this summer whenever the ball gets in his hands.

"It's fun, man," a smiling Gore said Tuesday. "Going through last year, it would take the whole (first) half for us to get across the 50-yard line. And now we're just moving the ball anytime we want."

It has been a while since the game was easy for Gore or the San Francisco offense.

After his breakout 2006 season, when he rushed for a franchise-record 1,695 yards and started for the NFC in the Pro Bowl, Gore lost his stride during a 2007 season that began with high expectations for both him and the 49ers.

The running back was hampered by an ankle injury and constantly faced defenses stacked with eight and sometimes nine defenders in the box to stop him.

He still produced a solid season, finishing fifth in the NFC with 1,102 yards rushing, ending the season as San Francisco's only legitimate offensive threat.

It has been different this year since Martz took over as San Francisco's offensive coordinator.

The 49ers displayed new explosiveness on offense, scoring 71 points in a recent six-day span that produced exhibition victories over Green Bay and Chicago.

Gore rushed for 80 yards on 14 carries in limited action with the first unit during the two games, propelling four 49ers scoring drives in their first four possessions against Chicago.

"This offense is better than when I had 1,600 yards," Gore said. "(Opponents) can't really sit safeties down, put eight, nine men in the box. So the big lanes are coming, and I have to take advantage of that."

Gore can't wait for the Sept. 7 season opener against Arizona, when the 49ers will unleash him with the rest of the new offensive attack. Gore and San Francisco's other starters might not play more than one series in Friday's exhibition finale against San Diego.

"He looks like he's enjoying himself," coach Mike Nolan said. "I know he's excited about the offense, and he's had real good communication with Mike Martz about his role."

Gore gives Martz most of the credit for a revamped offense that ranks sixth in the NFL in total offense during the preseason with 349.7 yards per game. The Niners rank third in scoring with a 25.7 average.

"We have a new leader, man, a new leader on the ship," Gore said.

"When he stands up in the room, and you hear him talk, you know that he knows what he's talking about. Everything is going to change this year. I'm going to be all over the place."