A BRAVE single mother has been caught on CCTV pinning down a jogger after he flashed her during a morning jog.

The personal trainer, who identified herself as Aia, was on her morning run yesterday when she claimed a man indecently exposed himself on Memorial Drive in Cambridge, Massachusetts.

Footage shows the heroic mum-of-two, a 185cm Israeli military veteran, then pinning him to the ground as she tried to get witnesses to call police.

"I'm not the victim to go after," she told WCVB.

"He pulled his pants down once and I didn't react too much, but as he came closer, he pulled them again. That's when I understood maybe it's not what I think it is."

Surveillance video from a nearby camera released by Massachusetts State Police shows Aia turning around to confront the unidentified suspect.

While the footage doesn't show the moment the man flashes Aia, according to police, the mother reacts when he tries to touch her arm.

She then chases him and manages to pin him down for four minutes while waiting for someone to call 911. But passers-by ignored her request for help.

"With all due respect, people, what does it look like? Romantic conversation? I'm holding him down yelling, 'Call the police'," Aia told WCVB.

"When I was holding him down, he was terrified. He was really really scared."

She was forced to call police herself while still holding him down, and that's when he escaped.

"The man resisted the woman's attempt to detain him and fled the area, last seen running down Amesbury Street," police said.

Aia told the publication said she didn't want another woman to be victimised.

"If I don't chase him, he's gonna scare some girl and get her all the way down. No," she said.

While police said they would have preferred she didn't tackle her alleged attacker, they commended her for standing up for herself.

"Good for her, you know, I think she put the fear of God in the guy," an unnamed officer told WCVB.

Aia told NBC Boston she didn't regret taking down the jogger, adding: "I was not ready to see his little d**k.

"I told him I am going to get you: I am going to get you darling."

Police are hoping for witnesses to come forward. They have described the man as a white male in his early 40s with a heavy build.

It's not the first time a woman has bravely taken on a man for indecent exposure.

In April, MMA star Joyce Vieira punched a man she claimed performed a sex act in Rio de Janeiro while she was taking part in a swimwear photo shoot.

Vieira - a specialist in Muay Thai and jiu-jitsu - decided to take action after the man, named in reports as Josenei Viana Ferreira, 26, refused to speak to her over his action.

Vieira immediately reported the case to police, with Ferreira subsequently arrested for committing an "obscene act", though he has since been released.

He claimed to have been "urinating" on the beach before Viera approached him.

"We feel powerless. It's very strange because he's going to be in the same city as me, and who knows he might be in the same places," Viera said.

She said she was inundated with messages from women who had been in similar situations but didn't file a report because they knew the suspects would end up being released.

"I think the punishment for these cases should be more severe," Viera said.