Your heart rate is monitored with the info displayed on a big screen so everyone can see just how hard you're working. Coupled with shouts of encouragement from the trainers, it's difficult not to give it your all. Which is precisely why these classes are so effective.
What is it?
You get a full body workout through a series of 12-14 exercises, performed for increments of 10-35 seconds. It may not seem much, but just one circuit has your muscles burning, your heart thumping and your face sweating.
The Speedflex is a hydraulic machine with adjustable resistance. There's no easy way to describe the machine other than a pillar with two handles that move up and down.
There's no real weight on the machine, so you get out as much resistance as you put in, meaning there's less chance of over exertion injuries.
With exercises that are adjustable based on ability, it's a class that is great for those that are just starting to get fit, or athletes looking for a new challenge.
A typical 45 minute session will comprise of between 5-7 rounds of circuits, including exercises such as clean and press, high pulls, bent over rows, squat press, mountain climbers and burpees - however no two sessions are the same.
If you want to see quick results and are willing to work hard, then this is the class for you. Over a 4 week period, our tester Charlie lost 1.5% body fat, and saw her visceral body fat (the important stuff) drop 4%, all through 3-4 classes a week and no change in diet.
Give it a try if:
If you like working out in a team environment, enjoy seeing exactly how hard you're working and like to sweat.
Give it a miss if:
You prefer working out alone, hate the 'all in it together' mentality, or like a slow paced exercise class.
What to wear:
Opaque leggings and a tank - this is not the time to test out whether your leggings are a little see through. Its chilly in the room to start with but you will soon warm up.
People have burnt 1200 calories in a class, no joke. Expect to burn between 500-700 for an average build and fitness level.
How much does Speedflex cost?
£30 per class, although memberships and 6 week blocks are available. These boutique style workouts aren't cheap but you will see results.
Currently just London and Newcastle.
Find out more at speedflex.com
See more from fitness fanatic Charlotte Watson at therunnerbeans.co.uk or follow her on Twitter @charliedwatson
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