Instead, the machines use a smooth hydraulic system to create a resistance which works as hard as you do – i.e, if you push hard, it will resist more.

Rocking up to my first session I was worried to see some seriously beefy blokes. However, trainer Stuart assured me that, due to the nature of the machines, I will not pump up my muscles but will instead tighten them. This also means you don’t ache nearly as much the next day – a serious bonus in my books.

With the same format as a circuit-training session, it’s hard work as you push yourself each time you go around, but motivation comes in the form of camaraderie from your fellow ‘flexers, plus you find out how many calories you burnt (550 in 40 mins for me) and how intensely you worked at the end of each session. I felt great afterwards and am excited to see what a difference six weeks makes...

Speedflex six-week experience (sessions held hourly, 7.30am-7.30pm, on weekdays), £450; monthly membership thereafter £250. Induction free of charge.  

33-36 Lombard Street, EC3V 9BQ  
Tube | Bank  
speedflex.com