Latest
issue
Get Attractions Management digital magazine FREE
Sign up here ▸
Jobs   News   Features   Products   Company profilesProfiles   Magazine   Handbook   Advertise    Subscribe  
Fitness
Short story

There’s been a surge in interest in short, but intense exercise regimes – known as high-intensity interval training – in the fitness sector. We investigate the background and benefits of this protocol for spas

By Kate Cracknell | Published in Spa Business 2012 issue 4


In the last few years, the health and fitness industry has seen the emergence of a number of shorter, results-driven workout concepts for ‘time poor’ consumers. Women-only franchises Curves and Vivafit have offered a 30-minute, circuit-based workout for some time, but are now being joined by the likes of Fit n Fast in Australia, where Quickie workouts are available in activities such as cycling, boxing and circuits – and where the intensity is being ramped up to challenge a younger demographic.

From a fitness equipment supplier perspective, milon’s eccentric and concentric resistance equipment has been designed to maximise results via a circuit workout that takes around 30 minutes. Power Plate also recently demonstrated a 20-minute concept which combines its vibration training platform with its new powerBIKE with vibrating pedals. Classes are getting shorter.

An elite heritage
They’re also getting tougher. Because what this is all leading to is the emergence of HIT (high-intensity interval training). Or should we say re-emergence? After all, in essence HIT is a training method that’s been around for many years in the elite sports arena.

Interval training in its modern form dates back to the 1930s, when Woldemar Gerschler (Germany) and Gosta Holmer (Sweden) used it to enhance the performance of their national teams. And in Finland, Lauri Pikhala was creating interval training programmes for runner Paavo Nurmi back in 1910.

Holmer dubbed the approach fartlek – Swedish for ‘speed play’ – thanks to the use of ‘faster than race’ pace. Concentrating on simultaneous speed/endurance training, the training protocol puts stress on both aerobic and anaerobic energy systems due to the alternating pace and intensity of the exercise. It’s now used the world over to offer variation in an elite athlete’s preparation throughout the year. And now it’s coming to fitness centres and gyms in the form of HIT. So how do we define HIT?

Defining HIT
Len Kravitz and Lance Dalleck – researchers at the University of New Mexico, in the US – define interval training as “high-intensity, short duration training sessions performed at workloads above the lactate threshold, marked by an abrupt increase in blood lactate that forces the muscle to revert from aerobic to anaerobic metabolism”.

Clearly this is hard to measure within a gym environment. However, in a review paper undertaken in February by New Zealand’s AUT University (see the Literature Review panel), HIT is defined as either working at over 75 per cent of heart rate maximum (HR max) or 75 per cent of maximum oxygen uptake (VO2 max), followed by rest periods.

Intervals vary from 1:1 (work:rest) ratios, to 2:1 or other variations depending on fitness levels. The rest phase can either be complete rest or dropping back to a moderate intensity to enable recovery.

“However, 75 per cent HR max and 75 per cent VO2 max are very different intensities and not to be confused as being the same,” stresses Randy Huntington, global director of marketing, performance, education and research at fitness equipment specialist Keiser. So there are no clear-cut guidelines as yet, other than that the work phases should be ‘hard’ or ‘very hard’.

Huntington, meanwhile, categorises HIT as a form of circuit training. “In 1953, RE Morgan and GT Anderson at the University of Leeds [UK] created circuit training – of which interval training is a subset – with Manfred Scholich going on to write the bible on interval/circuit training in 1986,” he explains. “There are many ways to do circuits and Scholich has already labelled them quite well, setting a series of criteria: sets, repetitions, load, type of exercise, order of exercises, number of exercises, rest interval, work interval and density.

“It’s important that a common vocabulary be established within the fitness industry, otherwise we’ll end up with fancy marketing names for programmes that have actually existed for over 40 years – and in some cases, where the roots are over 100 years old.”

Benefits of HIT
But if precise terminology and parameters are still to be decided, there does seem to be broad agreement on the benefits of HIT.

“Research shows that HIT delivers results that surpass conventional, steady-state training,” says Bryce Hastings, technical consultant for group exercise company Les Mills International (see sb08/3 p100). “These include accelerated aerobic conditioning, getting you fitter faster; an improved anaerobic threshold, letting you go harder for longer; improved insulin resistance and growth hormone changes, with enhanced hormonal responses; and the generation of athletic, powerful muscle, giving you the tone you dream about.”

Huntington adds: “Interval training has the potential to burn more calories than conventional aerobic/strength training and is an effective means of improving strength/muscular endurance. In addition, it has always delivered faster results. However, all this is at the potential expense of injury and endocrine burnout. It takes a while to adapt to such workouts, and in most cases adherence is less time than the required time to adaptation. If we’re to bring it into the gym, we need to make it fun so people will continue to do it, thereby gaining a cumulative effect.”

There’s also an argument that a HIT circuit may not deliver optimum results. Huntington continues: “In the late 80s and early 90s, Keiser developed the XPress Circuit for time-conscious, non-elite members. This was done in the full knowledge that circuit training will always compromise the true effectiveness of the five S’s – strength, speed, skill, stamina, suppleness – when they’re not done as discreet parts of a programme. Does this make HIT or circuit training bad? Absolutely not. It just means that the best results you can get will be less than the best result you could achieve by focusing on any one of the five S’s individually.”

For non-elite athletes, however, the benefits will already be very compelling. Not only that, but the AUT University/Les Mills review paper highlights benefits for a far more diverse range of exercisers than might have been expected. Gym-based use of HIT could, it seems, have a broad appeal.

Read more from this issue of Attractions Management magazine

View contents of Attractions Management 2012 issue 4
Research papers

A 2005 study of 38 elite cyclists, published in the Journal of Strength & Conditioning Research, showed that interval training leads to improved respiratory function, including better blood flow through the lungs and oxygen-carbon dioxide exchange. In the study, HIT increased performance by improving ventilatory threshold and VO2 max, boosting the body’s ability to use oxygen to generate energy.

Another study, published in the Journal of Physiology in July 2006, found improved adaptations in muscle cells after interval training in contrast to traditional steady-state endurance training. The study compared two groups of active young men over two weeks. One group engaged in traditional long-duration training for 90–120 minutes, while the other did four to six sets of sprint intervals (30 seconds all-out and four-minute rest intervals). It revealed superior adaptations in muscle tissue of the HIT group.

 



HIT led to improved respiratory function

Literature review
AUT University’s review of 45 published journal articles, carried out on behalf of Les Mills, focused on 24 papers that compared HIT with steady-state moderate intensity exercise. The authors focused on moderately trained recreational athletes through to those with general metabolic syndrome (including obesity and hypertension) as more representative of the general population. The training studies ranged from two to 20 weeks, with typically three to five sessions a week.

Some studies used supra-maximal intensity (up to a reported 170 per cent of VO2 max). But most used ‘work’ phases of around 90 per cent VO2 max – also described as 15-17 out of 20 on a self-rating scale of perceived exertion (hard to very hard). Sessions generally lasted around 40 minutes, including work and recovery phases: work phases were typically 30 seconds to two minutes; with recovery mostly one to four minutes of light to moderate exercise (70 per cent HR max).

In several studies HIT produced 5-10 per cent greater increases in VO2 max, often in less time. In some cases even greater differences were observed. Where the steady state group did experience significantly greater increases in VO2 max “it was patently owing to very big differences in training volume”.

In all cases, HIT produced greater improvements in anaerobic fitness, insulin sensitivity, endothelin function and body fat levels, with significantly greater reductions also observed in systolic and diastolic pressure in several studies.

Although often anecdotally quoted as a benefit of HIT, only one study specifically examined EPOC (excess post-exercise oxygen consumption) and found no significant difference compared with steady-state moderate intensity exercise.

Several of the papers commented anecdotally that subjects typically reported their enjoyment of interval-style training more than steady-state training, leading to good adherence.

The authors of the review found no evidence that repeat high intensity exercise bouts had a harmful effect on any of the populations. They also found no evidence that exercise intensity alone has a negative effect on resting hormone levels (testosterone, cortisol etc).

The milon circuit uses traffic lights to take exercisers through a 30 minute workout
The milon circuit uses traffic lights to take exercisers through a 30 minute workout
HIT has been proven to help generate powerful, athletic muscle
HIT has been proven to help generate powerful, athletic muscle
In several studies, HIT produced 5-10 per cent greater increases in VO2 max
In several studies, HIT produced 5-10 per cent greater increases in VO2 max
COMPANY PROFILES
Sally Corporation

Our services include: Dark ride design & build; Redevelopment of existing attractions; High-quality [more...]
instantprint

We’re a Yorkshire-based online printer, founded in 2009 by Adam Carnell and James Kinsella. [more...]
ProSlide Technology, Inc.

A former national ski team racer, ProSlide® CEO Rick Hunter’s goal has been to integrate the smoot [more...]
DJW

David & Lynn Willrich started the Company over thirty years ago, from the Audio Visual Department [more...]
+ More profiles  
FEATURED SUPPLIER

Iconic Liverpool attraction opens door to new operators
An opportunity to reimagine one of the UK’s most recognisable towers has been formally opened by Rivington Hark, as St Johns Beacon invites operators and partners to shape its next phase. [more...]
CATALOGUE GALLERY
 

+ More catalogues  
DIRECTORY
+ More directory  
DIARY

 

23-26 Aug 2026

Elevate Spa Riviera Maya Edition

The Riviera Maya Edition Kanai, Playa del Carmen, Mexico
29 Sep - 02 Oct 2026

Synergy - The Retreat Show

Pical Resort, Valamar Collection, Porec, Croatia
+ More diary  
LATEST ISSUES
+ View Magazine Archive

Attractions Management

2026 issue 1


View issue contents
View on turning pages
Download PDF
FREE digital subscription
Print subscription

Attractions Management

2025 issue 2


View issue contents
View on turning pages
Download PDF
FREE digital subscription
Print subscription

Attractions Management

2025 issue 1


View issue contents
View on turning pages
Download PDF
FREE digital subscription
Print subscription

Attractions Management

2024 issue 4


View issue contents
View on turning pages
Download PDF
FREE digital subscription
Print subscription

Attractions Management News

06 Apr 2020 issue 153


View on turning pages
Download PDF
View archive
FREE digital subscription
Print subscription

Attractions Handbook

2019


View issue contents
View on turning pages
Download PDF
FREE digital subscription
Print subscription
 
ABOUT LEISURE MEDIA
LEISURE MEDIA MAGAZINES
LEISURE MEDIA HANDBOOKS
LEISURE MEDIA WEBSITES
LEISURE MEDIA PRODUCT SEARCH
 
ATTRACTIONS MANAGEMENT
ATTRACTIONS MANAGEMENT NEWS
ATTRACTIONS HANDBOOK
PRINT SUBSCRIPTIONS
FREE DIGITAL SUBSCRIPTIONS
ADVERTISE . CONTACT US

Leisure Media
Tel: +44 (0)1462 431385

©Cybertrek 2026
Get Attractions Management digital magazine FREE
Sign up here ▸
Jobs    News   Products   Magazine   Subscribe
Fitness
Short story

There’s been a surge in interest in short, but intense exercise regimes – known as high-intensity interval training – in the fitness sector. We investigate the background and benefits of this protocol for spas

By Kate Cracknell | Published in Spa Business 2012 issue 4


In the last few years, the health and fitness industry has seen the emergence of a number of shorter, results-driven workout concepts for ‘time poor’ consumers. Women-only franchises Curves and Vivafit have offered a 30-minute, circuit-based workout for some time, but are now being joined by the likes of Fit n Fast in Australia, where Quickie workouts are available in activities such as cycling, boxing and circuits – and where the intensity is being ramped up to challenge a younger demographic.

From a fitness equipment supplier perspective, milon’s eccentric and concentric resistance equipment has been designed to maximise results via a circuit workout that takes around 30 minutes. Power Plate also recently demonstrated a 20-minute concept which combines its vibration training platform with its new powerBIKE with vibrating pedals. Classes are getting shorter.

An elite heritage
They’re also getting tougher. Because what this is all leading to is the emergence of HIT (high-intensity interval training). Or should we say re-emergence? After all, in essence HIT is a training method that’s been around for many years in the elite sports arena.

Interval training in its modern form dates back to the 1930s, when Woldemar Gerschler (Germany) and Gosta Holmer (Sweden) used it to enhance the performance of their national teams. And in Finland, Lauri Pikhala was creating interval training programmes for runner Paavo Nurmi back in 1910.

Holmer dubbed the approach fartlek – Swedish for ‘speed play’ – thanks to the use of ‘faster than race’ pace. Concentrating on simultaneous speed/endurance training, the training protocol puts stress on both aerobic and anaerobic energy systems due to the alternating pace and intensity of the exercise. It’s now used the world over to offer variation in an elite athlete’s preparation throughout the year. And now it’s coming to fitness centres and gyms in the form of HIT. So how do we define HIT?

Defining HIT
Len Kravitz and Lance Dalleck – researchers at the University of New Mexico, in the US – define interval training as “high-intensity, short duration training sessions performed at workloads above the lactate threshold, marked by an abrupt increase in blood lactate that forces the muscle to revert from aerobic to anaerobic metabolism”.

Clearly this is hard to measure within a gym environment. However, in a review paper undertaken in February by New Zealand’s AUT University (see the Literature Review panel), HIT is defined as either working at over 75 per cent of heart rate maximum (HR max) or 75 per cent of maximum oxygen uptake (VO2 max), followed by rest periods.

Intervals vary from 1:1 (work:rest) ratios, to 2:1 or other variations depending on fitness levels. The rest phase can either be complete rest or dropping back to a moderate intensity to enable recovery.

“However, 75 per cent HR max and 75 per cent VO2 max are very different intensities and not to be confused as being the same,” stresses Randy Huntington, global director of marketing, performance, education and research at fitness equipment specialist Keiser. So there are no clear-cut guidelines as yet, other than that the work phases should be ‘hard’ or ‘very hard’.

Huntington, meanwhile, categorises HIT as a form of circuit training. “In 1953, RE Morgan and GT Anderson at the University of Leeds [UK] created circuit training – of which interval training is a subset – with Manfred Scholich going on to write the bible on interval/circuit training in 1986,” he explains. “There are many ways to do circuits and Scholich has already labelled them quite well, setting a series of criteria: sets, repetitions, load, type of exercise, order of exercises, number of exercises, rest interval, work interval and density.

“It’s important that a common vocabulary be established within the fitness industry, otherwise we’ll end up with fancy marketing names for programmes that have actually existed for over 40 years – and in some cases, where the roots are over 100 years old.”

Benefits of HIT
But if precise terminology and parameters are still to be decided, there does seem to be broad agreement on the benefits of HIT.

“Research shows that HIT delivers results that surpass conventional, steady-state training,” says Bryce Hastings, technical consultant for group exercise company Les Mills International (see sb08/3 p100). “These include accelerated aerobic conditioning, getting you fitter faster; an improved anaerobic threshold, letting you go harder for longer; improved insulin resistance and growth hormone changes, with enhanced hormonal responses; and the generation of athletic, powerful muscle, giving you the tone you dream about.”

Huntington adds: “Interval training has the potential to burn more calories than conventional aerobic/strength training and is an effective means of improving strength/muscular endurance. In addition, it has always delivered faster results. However, all this is at the potential expense of injury and endocrine burnout. It takes a while to adapt to such workouts, and in most cases adherence is less time than the required time to adaptation. If we’re to bring it into the gym, we need to make it fun so people will continue to do it, thereby gaining a cumulative effect.”

There’s also an argument that a HIT circuit may not deliver optimum results. Huntington continues: “In the late 80s and early 90s, Keiser developed the XPress Circuit for time-conscious, non-elite members. This was done in the full knowledge that circuit training will always compromise the true effectiveness of the five S’s – strength, speed, skill, stamina, suppleness – when they’re not done as discreet parts of a programme. Does this make HIT or circuit training bad? Absolutely not. It just means that the best results you can get will be less than the best result you could achieve by focusing on any one of the five S’s individually.”

For non-elite athletes, however, the benefits will already be very compelling. Not only that, but the AUT University/Les Mills review paper highlights benefits for a far more diverse range of exercisers than might have been expected. Gym-based use of HIT could, it seems, have a broad appeal.

Read more from this issue of Attractions Management magazine

View contents of Attractions Management 2012 issue 4
Research papers

A 2005 study of 38 elite cyclists, published in the Journal of Strength & Conditioning Research, showed that interval training leads to improved respiratory function, including better blood flow through the lungs and oxygen-carbon dioxide exchange. In the study, HIT increased performance by improving ventilatory threshold and VO2 max, boosting the body’s ability to use oxygen to generate energy.

Another study, published in the Journal of Physiology in July 2006, found improved adaptations in muscle cells after interval training in contrast to traditional steady-state endurance training. The study compared two groups of active young men over two weeks. One group engaged in traditional long-duration training for 90–120 minutes, while the other did four to six sets of sprint intervals (30 seconds all-out and four-minute rest intervals). It revealed superior adaptations in muscle tissue of the HIT group.

 



HIT led to improved respiratory function

Literature review
AUT University’s review of 45 published journal articles, carried out on behalf of Les Mills, focused on 24 papers that compared HIT with steady-state moderate intensity exercise. The authors focused on moderately trained recreational athletes through to those with general metabolic syndrome (including obesity and hypertension) as more representative of the general population. The training studies ranged from two to 20 weeks, with typically three to five sessions a week.

Some studies used supra-maximal intensity (up to a reported 170 per cent of VO2 max). But most used ‘work’ phases of around 90 per cent VO2 max – also described as 15-17 out of 20 on a self-rating scale of perceived exertion (hard to very hard). Sessions generally lasted around 40 minutes, including work and recovery phases: work phases were typically 30 seconds to two minutes; with recovery mostly one to four minutes of light to moderate exercise (70 per cent HR max).

In several studies HIT produced 5-10 per cent greater increases in VO2 max, often in less time. In some cases even greater differences were observed. Where the steady state group did experience significantly greater increases in VO2 max “it was patently owing to very big differences in training volume”.

In all cases, HIT produced greater improvements in anaerobic fitness, insulin sensitivity, endothelin function and body fat levels, with significantly greater reductions also observed in systolic and diastolic pressure in several studies.

Although often anecdotally quoted as a benefit of HIT, only one study specifically examined EPOC (excess post-exercise oxygen consumption) and found no significant difference compared with steady-state moderate intensity exercise.

Several of the papers commented anecdotally that subjects typically reported their enjoyment of interval-style training more than steady-state training, leading to good adherence.

The authors of the review found no evidence that repeat high intensity exercise bouts had a harmful effect on any of the populations. They also found no evidence that exercise intensity alone has a negative effect on resting hormone levels (testosterone, cortisol etc).

The milon circuit uses traffic lights to take exercisers through a 30 minute workout
The milon circuit uses traffic lights to take exercisers through a 30 minute workout
HIT has been proven to help generate powerful, athletic muscle
HIT has been proven to help generate powerful, athletic muscle
In several studies, HIT produced 5-10 per cent greater increases in VO2 max
In several studies, HIT produced 5-10 per cent greater increases in VO2 max
LATEST NEWS
Butterfly sanctuary to host hot yoga during retreat at Jersey Zoo for Hotel de France
Hotel de France, located on the British Isle of Jersey, has created a wellness retreat package that includes a hot yoga session that will take place in Jersey Zoo’s butterfly sanctuary.
Warner Bros Discovery collaborates on upcoming Pompeii attraction
A new immersive attraction designed to transport visitors into the final hours of ancient Pompeii is preparing to open near the world-famous archaeological site in southern Italy.
Bob Rogers hands BRC to long-serving leadership team
Experience design company, BRC Imagination Arts, has completed a transition that sees founder Bob Rogers pass ownership of the business to four long-serving senior executives, while remaining actively involved with the company.
Rainer Maelzer joins Therme Group as chief entertainment officer
Rainer Maelzer, an experiential entertainment innovator, has been appointed chief entertainment officer by Therme Group.
Movie Park Germany reveals new Paramount attraction as part of its 30th anniversary celebrations
Movie Park Germany has opened a new Paramount Pictures-themed attraction as part of its 30th anniversary celebrations, using immersive storytelling and adaptive reuse to reinforce the park’s longstanding “Hollywood in Germany” positioning.
Therme Manchester reveals 90:90 strategy – 90 per cent of the UK population within a 90-minute drive of a Therme
Therme Manchester’s 28-acre development, which will include interconnected glass pavilions that measure 65,000sq m, will be the largest bathing and wellbeing attraction in the world once complete, according to prof David Russell, CEO of Therme UK. 
Efteling expands family offer with new Hooghmoed drop tower
Efteling has opened Hooghmoed, a new family drop tower designed to broaden the appeal of its recently launched Sirene Island themed area and introduce younger visitors to thrill attractions.
Universal and Puy du Fou projects point to rise of Oxford–Cambridge corridor
A proposed Puy du Fou development near Bicester and Universal Destinations and Experiences’ planned resort in Bedford are emerging as part of a wider transformation of the Oxford– Cambridge Growth Corridor into a major centre for UK leisure and tourism inv
Shedd Aquarium upgrades its visitor experience with new Immersion Theater
Shedd Aquarium has opened the Immersion Theater developed in partnership with SimEx- Iwerks, as part of a wider strategy to enhance the guest experience and create additional revenue opportunities.
UK government cuts VAT on attractions to boost summer visitor economy
The UK government has announced a temporary reduction in VAT on visitor attractions and children’s meals as part of a summer cost-of-living support package designed to stimulate the visitor economy and encourage family days out.
Joy as a radical act: Yinka Ilori launches solo exhibition celebrating the rebellious power of spreading happiness
As designer Yinka Ilori prepares for his first solo gallery show in London, he speaks exclusively to CLADmag about his mission to spread joy, the power of play, and his bold approach to using colour (including the colours you won’t see in his work).
Government of Thailand reveals it is courting major theme park operators
The government of Thailand is exploring plans for a THB300bn (£6.3bn, US$8.3bn) entertainment complex in the country’s Eastern Economic Corridor (EEC), with officials proposing a large-scale theme park and sports destination as part of a broader tourism and economic development strategy.
+ More news   
 
COMPANY PROFILES
Sally Corporation

Our services include: Dark ride design & build; Redevelopment of existing attractions; High-quality [more...]
instantprint

We’re a Yorkshire-based online printer, founded in 2009 by Adam Carnell and James Kinsella. [more...]
ProSlide Technology, Inc.

A former national ski team racer, ProSlide® CEO Rick Hunter’s goal has been to integrate the smoot [more...]
DJW

David & Lynn Willrich started the Company over thirty years ago, from the Audio Visual Department [more...]
+ More profiles  
FEATURED SUPPLIER

Iconic Liverpool attraction opens door to new operators
An opportunity to reimagine one of the UK’s most recognisable towers has been formally opened by Rivington Hark, as St Johns Beacon invites operators and partners to shape its next phase. [more...]
CATALOGUE GALLERY
+ More catalogues  
DIRECTORY
+ More directory  
DIARY

 

23-26 Aug 2026

Elevate Spa Riviera Maya Edition

The Riviera Maya Edition Kanai, Playa del Carmen, Mexico
29 Sep - 02 Oct 2026

Synergy - The Retreat Show

Pical Resort, Valamar Collection, Porec, Croatia
+ More diary  
 


ADVERTISE . CONTACT US

Leisure Media
Tel: +44 (0)1462 431385

©Cybertrek 2026

ABOUT LEISURE MEDIA
LEISURE MEDIA MAGAZINES
LEISURE MEDIA HANDBOOKS
LEISURE MEDIA WEBSITES
LEISURE MEDIA PRODUCT SEARCH
ATTRACTIONS MANAGEMENT NEWS
ATTRACTIONS HANDBOOK
PRINT SUBSCRIPTIONS
FREE DIGITAL SUBSCRIPTIONS