Bitch Boxer, ***; Chapel Street, ****, Underbelly, Edinburgh

Chloe Jackson has just one more fight to win before she gets the chance to live her dream - to box for Team GB at the Olympics. So begins Bitch Boxer, one of five plays that have been brought up to the Fringe by Old Vic New Voices (OVNV), a new venture from the London theatre for 2012 giving a platform to young talent and their freshest stories.

And you don't get much more box-fresh and up-to-the-minute than a monologue about a female boxing star bidding for glory in East London. But while Nicola Adams is still basking in the golden glow of her real-life happy ending, our fictional heroine's future is less assured. Hailing from the school of hard knocks, she took up boxing aged 11 when her mother walked out but when her beloved father/trainer dies suddenly, everything she has worked for is thrown into jeopardy.

Written and performed by the expressive, energetic Charlotte Josephine, Bitch Boxer is in the finest tradition of fighting dramas - a pumped-up, underdog monologue with a big heart, delivered in a hail of upper-cuts and a spray of sweat. Josephine puts in an impressively physical performance broken up with tender moments. It's more coming-of-age fable than insight into life in the ring but then, as she reminds us, "every fighter has a reason" - and in this most emotional of sports, the two are often intimately linked.

Returning servicemen, sex workers and teen obesity are among the hot potatoes tackled in the other OVNV plays. In Chapel Street, Binge Britain is put under the microscope in a simple tale of a schoolgirl and a twentysomething lad whose paths cross, fatefully, one Friday night.

Part spoken word, part play and delivered through microphones like stand-up, Luke Barnes' two-hander glitters with promise and pep. There's sharp-eyed humour to his picture of modern Britain and teenage life - all Kardashians, sequins and shots - but there are a troubling undertones, too - the angry drinker who threatens the pub landlord with his shotgun, the fact that "no-one's got a job and everyone lives with their mum" and, most crucially, the deadening lack of any ambition greater than getting blind drunk at the weekend.

Cary Crankson, charming as Joe the wastrel who gradually reveals the yawning extent of his disaffection and Ria Zmitrowicz as a Vicky Pollardesque teen motormouth put in two of the wittiest and most engaging performances I've seen this Fringe.

To 26 August (0844 545 8252)