Dr Rosena Allin-Khan waves from her Fiat 500 and drives down Balham High Road. It is not the archetypal boxer’s car. Rosena Allin-Khan is not the archetypal MP.

The hour before, we trained at Balham Boxing Club, a rusted shed on Tooting Bec Common in south London. It is slightly larger than the sort of mobile cabin primary lessons are taught from when a school renovation inevitably stalls. Worn heavy bags hang from scaffolding poles. Pictures of Muhammad Ali sit between promotional posters for amateur events, the showers make you want to dance in and out of a pair of flip flops while changing.

“Winston and Tasha here, they’re the ones who do the best gruelling workouts. They’re the ones that make grown men cry,” Allin-Khan says while Tasha wraps my hands beside the ring.

We do circuits. Shadow boxing with dumbbells, reverse crunches and shuttle runs before getting in the ring for pyramid combinations on the focus mitts. As well as training here, Allin-Khan is the team doctor. She runs with the team at shows, providing first aid ringside and medically assessing fighters’ fitness to box before they make the walk.

“It’s really, really come a long way in terms of safety. I wouldn’t be doing it if I didn’t think it was safe,” she says. It feels like she’s trying to get ahead of a criticism that’s not coming. “It’s really fun, particularly if you like boxing.”

The Labour MP has boxed since university, where she studied medicine, but does not compete - a black eye doesn’t help bedside manner. After graduating the junior doctor worked in what’s now her constituency hospital, St George’s, in the A&E department. It was her last job before successfully contesting the Tooting by-election to win a seat in the House of Commons. Although, that implies a sense of finality. In fact Allin-Khan still picks up shifts when she can, working 12 hours on the same ward in between parliamentary sessions.

It’s a work ethic that could be genealogically traced back to her mother Maria, a famous Polish singer during the sixties who fell in love with a Pakistani man she met on tour in London. She gave it up and worked three jobs to support the family, in a petrol station and as a childminder and cleaner. Rosena’s been in Tooting ever since. Her assessment of childhood: “I didn’t have the easiest upbringing.”