“Your heart’s beating faster, you feel all these eyes on you, your body reacts with panic.” No, it’s not the discarded first line of Eminem’s Lose Yourself, but Alex MacLaren’s description of how his students feel in work meetings, job interviews or even the pub. MacLaren teaches improvisational comedy at the Spontaneity Shop in London. At first, its courses attracted performers. Now, he estimates half his students are seeking help with anxiety or confidence.

It’s a trend noted by other improv teachers. In Manchester, Brainne Edge runs workshops as head of ComedySportz UK. In the past five years she’s seen the proportion of non-performers attending her courses rise to around 75%.

Sarah Farrell, 40, a graphic designer from Manchester and Ryan Kelly, 34, head of digital at a London creative agency, are two such students. Farrell was struggling with social anxiety and depression. Kelly was preparing to be best man at a friend’s wedding and was dreading the speech. They are both fans of the TV show Whose Line is it Anyway? and imagined how the confidence needed to perform in an improv show could help them.

“This was my first time speaking in front of 200-odd people,” says Kelly. “I didn’t relish the thought, so I thought I’d do something that would make me more confident.” Farrell already attended therapy sessions, which she finds useful, but felt she needed something more. “I was dealing with suicidal thoughts at the time, [so] maybe it was to distract myself from those long Saturday afternoons,” she says.

Going into the first session was intimidating (“I made my friend come with me – I wasn’t that brave!”), but Farrell found a welcoming environment.

Edge says: “We work hard to make it a comfortable space for people to try things and play and not worry about consequences.” MacLaren agrees: “We have to move people from mild social anxiety … into a playful and safe space.”

The teachers identify improv principles that could help to combat anxiety. First, they try to remove the fear of failure – teaching students that there is no “wrong” thing to say. “That is incredibly powerful because we are so used to trying to get the answer right,” says MacLaren.

Games help students get used to speaking their thoughts. “We did word disassociation games where you run around the room, point at things and say a word that it wasn’t,” says Kelly. “It teaches you to have a better link between your brain and your mouth.”

Farrell stopped overanalysing her thoughts so much. “You try to be less inside your head,” she says. “With anxiety and depression you’ve always got the running commentary about how bad and useless you are. Getting that to shut up and just talking is massively helpful for me.”

Once participants are comfortable with the possibility of messing up, they can start saying yes to new experiences – or in improv, “Yes, and”. It means embracing and building on character and scenario ideas others bring to the stage. In real life, it could mean accepting a social invitation or simply participating in a conversation. “You learn to say yes even when you don’t know where you’re going to end up,” says MacLaren.

Comedian Pippa Evans performs improv at the Comedy Store and with Josie Lawrence as part of Glenda J Collective. She also runs Improv Your Life, for non-performers. “I started doing it because I found improvisation really helped me,” she says. At work, she moved from being “an absolute control freak” to embracing her colleagues’ suggestions. It also helped her let go of the need to have a five-year life plan: “Improvisation allowed me to be open to a life where I don’t know what’s at the end of the tunnel and therefore appreciate what’s happening in the moment.”

Evans hopes to share these benefits and relates parts of her course to everyday situations. In her game “That reminds me”, a single word prompts a series of anecdotes, each inspired by the last, highlighting that every contribution keeps conversation flowing.

Most beginner courses don’t involve a performance, beyond working with classmates. But this can be too much. “We’ve had that a couple of times,” says Edge. “People have turned up and gone, ‘This is very big and loud, I’m not ready for this yet.’”

For Kelly, the course was fun and useful: “It made me a lot more relaxed; I actually enjoyed the [best man] speech.” He’s since noticed extra benefits. “I used to not enjoy big social things – working the room was very stressful,” he says. “I now look forward to those more. People aren’t judging you in real life. Don’t be afraid to put your thoughts into the conversation.”

After completing her course, Farrell signed up for the next level, which concluded in a performance. She’s since been back for more and would do it again. “You stop playing when you get older – everything becomes serious business – but it releases a lot of pressure,” she says. “I think [improv] saved my life. It opened me up to being a better version of myself.”

In the UK, Samaritans can be contacted on 116 123. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is 13 11 14. Other international suicide helplines can be found at www.befrienders.org.