A man's world for female mixed martial artist Katharina

The training hall is located on the outskirts of Neuss. Katharina Lehner goes out there from Cologne once a week for her training. Children are running around the small gym, still full of energy after their sports class. Gradually, they are replaced by older athletes, who greet each other with a handshake and a pat on the back. Kathi clearly belongs to the group - but she is the only woman there.

After warming up, the next series of exercises are done in pairs. Kathi teams up with her boyfriend. "It's fun to train with him. We're comfortable with each other because he knows me so well," she says. "We kid each other - and if we're mad about something, we get to hit each other really hard," she adds with a laugh.

But there won't be any punches today. Today's training focuses on wrestling. They sneak around each other, waiting for the right moment to attack. It almost looks like a dance.

Training for a rough sport

Most of Kathi's training partners are good friends too. They all know that she can hit just as hard as any man. Their trainer Max admires Kathi's power. "Male or female, that doesn't matter for anyone here. We're all doing full-contact martial arts. She really found her way in, and that's something I truly respect," he says in this video showing Kathi training.

Although full-contact combat also involves being in close physical contact with men, Kathi says she's never felt anything even remotely erotic while training with them.

She does notice a difference when she trains or fights with women. "They don't strike as hard, and you don't need as much power for grappling. The opponents are easier to beat," she explains.

The supreme form of martial arts

Kathi got her Bachelor of Arts in Health Management. During the day, she has a part-time job with a German sports publishing company. Her short work shifts allow her to dedicate the rest of her time to her passion.

Training has become Kathi's main interest in life. She goes running in the morning, and in the evening she's in the sports club, where she practices all the different techniques she needs to practice her discipline, mixed martial arts, also called MMA. It's a mixture of Thai boxing, wrestling and grappling on the ground, and also includes aspects of other martial arts.

MMA is a full-contact combat sport. Kathi calls it "the supreme discipline of martial arts."

She is one of 27 women in Germany who do mixed martial arts. These athletes come from different social backgrounds - one of them even has a PhD.

Kathi is the best in the country: She's currently the first in a national ranking.

To achieve this, she pushes her body to its limits every day - and is always exhausted in the evening, she says. "I might party after a fight. But not for long - because if I party too much, then I can't train for two days. I don't think it's worth it."

Not just for the looks

Kathi began bodybuilding when she was 15. But that wasn't enough for her. "You work out every day just to look good. At then what? Those competitions with anorexics posing for a half hour on a stage - that wasn't for me."

So she moved on to martial arts. "It really contributes to developing your character. You learn how much energy you have to invest in achieving something," she says. "You learn to keep a cool head in difficult situations. When you receive a bad blow, you need to figure how to free yourself from the situation."

Giving and taking

Kathi used to have lots of piercings, but she had to get rid of all her jewelry when she started doing martial arts. But she can still show off her tattoos. Her tattooed neckline catches the eye right away, but others are less conspicuous.

One of her favorite sayings is tattooed on her thigh, a Rocky Balboa quote: "Life ain't about how hard you hit; it's about how hard you can get hit and keep moving forward."

Kathi has never been knocked out, and she hasn't knocked anyone down yet either, even though it's a really rough sport. She mentions that it's completely normal to see blood flowing.

"I've already broken someone's nose and hand, and I got a really bad liver punch once. But nothing worse," she says, adding that she once got a worse injury while snowboarding.

'My children will have to wrestle'

Kathi grew up in the countryside, in a village called Schwandorf near Regensburg in "beautiful Bavaria," as she calls it. But despite the beauty of the region, she found it boring after a while. There weren't that many possibilities for sports either: "There wasn't anything except soccer."

She moved out of her parents' home when she was 16 and moved on to Munich to study at the age of 18. Since 2012 she's been living in Cologne's student district, the "Kwartier Latäng."

Her parents weren't very excited when she took up martial arts. Her mother particularly struggled with the fact that her daughter was brutally fighting in a boxing ring. But now her parents are proud of her success and attend her competitions.

Kathi also plans to pass on her passion for martial arts: "If I have children, they'll definitely have to wrestle. But no boxing - that's just not for kids."

Germany, or someplace warm

Kathi's goal is to take part in four or five competitions this year. She can't plan the future any further ahead. She might like to leave Germany one day, to live somewhere warm. But she enjoys living here, no matter where in Germany. She's spent time in many different cities with her competitions - in the West and in the East - and says she's never noticed any differences between the people in both parts, except the regional dialects.

October 3 and German reunification aren't important issues for Kathi. "I didn't experience it all myself. Of course it's a good thing that the Wall came down and that people from former East Germany are now free."