Introducing our new, 45 minute BMF HIIT classes. Shorter, more intense classes to fit around your schedule and help with fat-loss.

The new classes will run for 45 minutes and just like our normal BMF classes will be suitable for all fitness abilities. Your membership will include all BMF classes and run clubs too.

Try your first class absolutely free.


If you’re looking for a maximum-effort, minimum-time training regime then you’re on the right page! High intensity interval training, or HIIT, is the solution for time-poor, but enthusiastic people. HIIT training is similar to 'Tabata' and is highly effective for improving aerobic fitness, weight-loss and fat burning.

What is HIIT?

HIIT itself involves alternating bouts of both high and low intensity exercise to increase the amount of high intensity work performed. Here’s the science-y bit: The low intensity, or rest periods, allow for the buffering and clearing of lactic acid from the blood which then allows you to perform another bout of high intensity work.

This type of training method is nothing new. For years, people have run up and down hills, done stop-and-start sprinting and also done traditional interval training in order to get that extra ‘oomph’ from their training. But HIIT is different. It involves working extremely hard for a short period of time, whilst gaining a similar amount of benefit as a typical session of endurance training.

So, is HIIT training like circuit training?

The simple answer is no, the only similarity these two workouts have is that they’re time-efficient workouts. That’s it. Circuit training is primarily a resistance training workout. You would work through nine to 12 exercises (such as push ups, jumping jacks or kettle bell swings) for a period of 15 to 45 seconds with little to no rest in between.

What about Crossfit? Are HIIT and Crossfit the same?

Again, no, Crossfit is also a time-efficient workout but that’s it again. Crossfit is all about your time challenge. A Crossfit session encourages you to complete a set of exercises as fast as you can (great for that output but not so great for your body form or positioning – watch out for injuries!).



Studies have shown that repeated HIIT sessions three days per week over a six-week period is a powerful method of increasing whole body muscle capacities to oxidise fat and carbohydrates in untrained individuals. In non-jargon this means that HIIT workouts can increase your metabolism for up to 36 hours after a session, thereby burning a LOT more calories per workout.

We know that HIIT has some fantastic benefits on both health and performance. Generally, we see HIIT used for one or more of the following three reasons:

Improved performance
Improvements in body composition
Health benefits

How does HIIT burn fat and why is it best for fat loss?

For a lot of people, one of their major goals is weight loss, either in the form of ‘dropping a dress size,’ or ‘getting a beach body.’ The fitness industry itself seems to be overwhelmingly based on body composition too. For this reason, we will spend a little bit of time looking at how HIIT can help improve your figure.

HIIT has repeatedly shown results of a greater impact on fat loss than traditional steady state exercise has. Want to know what the secret sauce is? Keep reading…

How to HIIT

HIIT can be any kind of exercise but let’s keep it simple and say you were going to go outside and run for 20 minutes. Not a gentle jog but a flat out pelt.

In the first 10-20 seconds you are officially nailing it, you’re running like the wind, running like you stole it, running like a rabid dog is on your heels and is hungry for your running shoes. Why are you doing so well? Because you’re using a high-intensity energy source known as phosphocreatine. 

You’ve hit the 20 seconds mark and are seriously considering competing for a spot on the GB Olympic running team when…you start to slow. That lovely phosphocreatine is running low and more lactic acid is being produced by your body to try and keep you going. Mentally you will still be running as fast as you can but physically you’d be slowing down because of anaerobic glycolysis (you’re getting tired!) and your lungs are working overtime.

There’s a magic ingredient that COULD keep you running faster, for longer: OXYGEN.

When you’re running flat out your body can’t get enough oxygen around your body and THAT’S why you struggle. Imagine if there was a smart way to train our bodies to use the optimal amount of phosphocreatine and oxygen to: 

Get fit - Lose weight - Feel great 

There is: HIIT!

With HIIT, you alternate short bursts of very intense exercise (such as 10-20 seconds of sprinting) with periods of lower intensity (such as one minute of walking).The higher intensity periods create a metabolic demand that is very effective for long-term fat loss and overall conditioning. The lower intensity periods let you recover and use the aerobic energy system.


HiiT for the over 50’s and for people with health conditions

HIIT has also demonstrated some fantastic health benefits, which for us at BMF is our key concern for all our members. Recent studies have shown that when using HIIT there have been improvements in lipid profiles, reduced blood pressure and an improvement in overall myocardial function in patients suffering with cardiovascular disease. Type 2 diabetic patients showed reductions in blood glucose along with increased mitochondrial activity and GLUT4 expression following two weeks of three x 20 min HIIT sessions per week.

Using HIIT to help improve health has not only shown to be effective, but also safe.  HIIT has been used effectively with no adverse reactions on some of the following patients.

Type 2 diabetics
Patients suffering from angina
Patients suffering from heart failure
Patients following myocardial infractions
Post cardial stenting and coronary artery grafting


Making the most out of your HIIT session

Pick a goal

Firstly, you need to understand your goal for the session. Spend some time working out exactly what you want to achieve from the HIIT workout.

Choose your weapons

So, you know what you want to achieve during your HIIT routine, next up is how you’re going to achieve it. Once you have the goal you must decide which energy system you want to task. The relationship between duration, intensity and rest is very important to help you achieve the goal you set out.

Exercise selection – just KISS

We can’t all be pro athletes so when you’re designing your HIIT workout it’s better to ‘keep it simple (stupid)’. You want to operate at the highest intensity possible and that will be difficult to achieve if you are performing exercises which require a high skill level. Stick with simple exercises that involve multiple joints and large muscle groups to see the best results.

Frequency of training

It really depends on those goals we talked about above, as well as your own fitness levels and the time you have available. Adam Rosante, certified personal trainer and author of The 30 second body recommends three to four times a week max (with a day or two of rest in between them.)


Want to try a HIIT session at home? Here’s an example:

Complete the following exercises as fast as you can with minimal rest in-between. Remember to maintain good form throughout the circuit:

10 press ups
10 squat thrusts
10 squat jumps (keep going!)
10 burpees
10 star jumps (you can do it!)
4 x 40m sprints

Have around two minutes of rest between circuits. Then try to repeat the circuit a total of five or six times (with the rests in the middle).

Don’t do it alone

HIIT is a fantastic workout to do in a group. The camaraderie, group energy and a little bit of competition are all fantastic ingredients to make your HIIT dose a big success.

Want to find a HIIT class near you? Click here to find your next class!


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HIIT Class Timings
Venue Monday Tuesday Wednesday Thursday Friday
Abington Park         11:30
Bellahouston       18:00  
Blackheath   07:00      
Callendar Park       18:00  
Cannon Hill Park - Birmingham         11:30
Clapham Common         06:30
Ealing Common     07:00    
Hyde Park     09:30    
Kelvingrove Park 19:15        
Lydiard Park   10:00      
Meadows     17:30    
Peckham Rye Park     06:30    
Pittencrieff Park     17:30    
Pittville Park     10:00    
Platt Fields   18:00      
St Albans - Verulamium Park     09:30    
Stamford Park       18:00  
Watford - Cassiobury Park     18:00    
Worcester Woods Country Park   10:00