When it comes to fitness classes, the maxim to remember is the best form of exercise is the one you actually do. Any personal trainer worth their salt will tell you that it’s pointless signing up for a weekly high-intensity, muscle-building circuits session when actually you really want to be doing Pilates. You’ll just go once or twice and then give it up.

It’s time to stop choosing your fitness classes based on calories burned, and instead pick a workout you’re going to love (and, importantly, stick with). And, if you’re based in the capital, we’ve got good news: London’s high-end gyms and health clubs are home to hundreds of unique and effective fitness classes. So, where to start? From leg-burning spin sessions to full-body cardio blasts and targeted strength training, these are the best fitness classes in London guaranteed to get hearts racing.

Psycle Strength at Psycle

When you hear ‘Psycle’, it’s likely the first thought that comes to mind is spinning. However, there’s a lot more than meets the eye to this fitness brand, which established itself in the capital in 2013 as one of the first pay-as-you-go spinning boutiques. Today, Psycle offers five different workout classes: Ride, Barre, Reformer, Yoga and Strength.

While they all do the job (and by that, I mean make you sweat and feel great afterwards), it’s the Strength class which sits at the top of our list. Split across three classes – Lift, Condition and Sweat – have been co-created by Amy Claire, Psycle Strength Coach and Nike Trainer, and head of Reformer and Strength, Matt McElligott. Each Strength class is designed to test your mental and physical capacity in a challenging but fun way with a satisfying ache guaranteed the following day – and our favourite is the Sweat session that uses SkiErgs, rowing machines and weights, to challenge your strength and cardiovascular endurance. Expect multiple stations and constant challenges.

Classes from £26, membership from £100 per month, visit psyclelondon.com

BarreSignature at BarreCore

Since bringing its ballet-inspired low-impact, high-intensity workout to London in 2011, BarreCore has become a workout phenomenon, now boasting nine locations in the capital and a further three across the UK. Pippa Middleton, Claudia Schiffer and Poppy Delevingne are all known to be fans of the BarreCore Method, which prides itself on safely exhausting muscles and inducing the famed ‘BarreCore Shake’ without putting pressure on joints.

There are now a whole span of classes on offer but long-term fans still swear by the original Barre Signature. This 45-minute class can be adapted for all levels, making it a great choice if you’re new to barre, and combines bodyweight resistance, barre work and light weights in high repetitions for a full-body workout that hits all the major muscle groups.

Classes from £30, membership from £187 per month, visit barrecore.com

The Original HIIT Workout at Barry's

Barry's has become a London institution and is now celebrating its 11th year, having built an empire of fitness studios in London, Manchester and Liverpool. There's a reason its signature HIIT class has become a thing of legend and inspired a cult-like following across the globe. Available at its seven London locations, and always taking place in the infamous Red Room, the workout follows a 50 per cent treadmill, 50 per cent strength training formula, with workout focus changing daily so you're always challenged and never bored. While there's no denying that this is a tough workout (and we know we said it's not all about the numbers), if you are looking to torch some serious calories, Barry's promises to burn more than 1,000 in a single 50-60 minute class while raising your metabolic rate by 15 per cent.

Classes from £26, membership from £160 per month, visit barrys.com

Full Body at Kobox

If you’ve always fancied trying your hand at boxing but have been put off by intimidating rings, warehouse gyms and the thought of taking a glove to the face, Kobox is the solution you’ve been looking for. Its two stylish locations in Chelsea and Marylebone offer a welcoming place to learn proper jab and hook technique in classes that combine fast-paced combinations with traditional functional exercises.

Specific 50-minute classes targeting the core, upper and lower body are on offer but for a great all-rounder choose the full-body workout – and don't miss the Lunch Box for a speedy afternoon session that will leave you feeling pumped (and includes a free shake). Let the music and flashing lights sweep you up as you spend half the class performing fast-paced six-punch combinations at the bag, before switching to mat exercises designed to target the core and lower body. This may be the most fun you've ever had in the gym.

Classes from £25, membership from £185 per month, visit koboxboxingclub.com

Ride at Boom Cycle

If you find the range of classes on offer at a lot of gyms a little dizzying, head over to Boom Cycle, where they make things simple by offering just one highly effective workout. A classic spin class, complete with nightclub atmosphere, chest-thumping beats and high-energy trainers, every class is adaptable to your personal fitness level, with all participants encouraged to set their own goals and push to meet them. As with most classes of this type, how much you love it will often come down to the instructor, so try out a few to see whose style suits you best.

Classes from £19, membership from £180 per month, visit boomcycle.co.uk

Rocket Yoga at Blok

Hip East London gym group Blok – which has outposts in Shoreditch, Clapton and Leyton – doesn’t believe in a one-size-fits-all approach to training. Instead, upon joining every member is encouraged to choose three training categories to focus on (strength, endurance, skill, flexibility and reset), with a programme of at least three classes per week created to cover your chosen specialisms. The benefits of this cross-training method are myriad: lower injury rates, less chance of boredom and faster progress, to name a few.

Classes are highly tailored, with some surprisingly niche options on offer, including an hour-long class dedicated to handstands, as well as strength-based calisthenics, breath workshops and sound healing. Yoga is one of Blok’s specialties and, if you’ve got a solid foundation, it offers a number of more advanced classes and twists on classic flows to take your practice to the next level. Our favourite is Rocket Yoga: a fast-paced class that utilises the principles of Ashtanga yoga but does away with long holds to offer inversions and arm balance sequences that improve flexibility and stamina.

Classes from £23, membership from £90 per month, visit bloklondon.com

Band Burn at Equinox

Equinox’s three London locations rank among some of the most luxurious health clubs in the capital, with spas, members' lounges and steam rooms as standard. But, before you can sit back and relax in the sauna, you’re going to need to earn your downtime. Enter Sculpt classes. Otherwise known as body conditioning classes, these workouts range from dance-inspired sessions to core-focused classes – and our favourite is the Band Burn. Designed to create lean muscle, perfect posture, and more mobile joints with just a band and gliding disc, expect plenty of squats, pushes, pulls, lunges, and rolls in timed intervals. Will you be exhausted? Yes. Will it be worth it? Absolutely.

Memberships from £270 per month, visit equinox.com

Wattbike at Third Space

Third Space doesn't do things by halves. At its 13 venues in key London locations, including Moorgate, Mayfair, Canary Wharf, Soho and Islington, you'll find acres of floor space, rows and rows of equipment, yoga studios, pools, saunas and quite possibly the chicest changing rooms in the city. Accordingly, the range of classes on offer is equally all-encompassing, with 44 workouts offered across disciplines including swimming, dance, combat, strength and conditioning, yoga and athletic training. The star of the show, however, is its Wattbike class. Endorsed by British Cycling, this innovative class replicates the feel of a real ride while also analysing your technique and adapting the challenge to maximise performance.

Memberships from £240 per month, visit thirdspace.london

Read more: The best luxury gyms and health clubs in London