A group of women skate around a banked track. As the whistle blows, they pick up speed.

Two women break ahead of the pack, and as suddenly as one lifts her arm to strike the other, they are both hurtling over the outside rail with helmets and fists flying.

The crowd roars in support of the rumble.

The non-stop antics of full contact Roller Derby bring all the showmanship of entertainment wrestling to the roller circuit.

This is the sport where body slams, throws to the ground, hair pulling and general clobbering by folding-chairs are all commonplace sportsmanship.

After a 21-year absence from the world of television, the San Francisco Bay Bombers returned to KOFY 13 on March 14. The hour-long broadcast was full of jam session excitement and plenty of skirmishes, knockouts and even the occasional strangulation that occurred between the Bombers and the Orlando Thunder playing in the Kezar Pavilion.

This mixed-gender league calls the Kezar Pavilion, on the Haight end of Golden Gate Park, home base.

"Kezar is a great place to see roller derby. Every seat is a good seat," said the general manager of the Bombers, Jim Fitzpatrick.

Fitzpatrick has been the GM of the world champion Bombers for about two years and led them to the Championship his first year on the team. The former roller derby skater thought his life in this sport was over when he retired after too many shoulder injuries, but "the sport just keeps calling me back," he said.

Lisa Hartmayer, Bomber and full-time registered nurse, answered that calling two years ago and has been skating with the team ever since. Even though Hartmayer is no stranger to rinks and skates - she plays hockey once a week with a local league - though her calling was a bit more atypical.

"I had grown up watching roller derby, but it was an April Fools joke with my boyfriend that really got me to try out."

Despite getting three head injuries in one game, she has shown no signs of slowing down.

"I don't think I have any permanent damage yet. But, I'm a nurse and often I think that I should know better to be involved in such a dangerous sport. I help people at work, but seem to hurt them on the track," said the 30-year-old jammer.

Finding time to get practices in has been the biggest challenge for the team. Practices happen with most of the team about once a week but some of the members live or work outside of the Bay Area - some in Los Angeles and Las Vegas. But the Bombers don't let that get in the way of their success on the track.

The version of roller derby that the Bombers participate in takes place on a inclined circuit track. Their banked track, which is 52 feet wide by 96 feet long, is what you need in order to have a "real" Roller Derby game, according to the American Roller Skating Derby.

The public can also find an opportunity to jam on the circuit when the Bombers are not playing. Practice sessions are available daily before the game and on weekends along with the Saturday night games.

The next game will be at the Kezar Pavilion on March 21 at 8 p.m. Student of SF State can gain admittance at the door for $5 if they show their school I.D. General adult admittance is $10. The next game on TV will be the Bombers battling against the Brooklyn Red Devils, April 18, on KOFY TV20 Channel 13.