The Les Mills Difference: Our Science

All Les Mills fitness programs are born from the expertise of world-class program directors, the talent of top choreographers and many hours of practice, testing and fine-tuning. But that’s certainly not all. Every program is designed in line with the very latest industry research. This comprehensive research and development ensures that Les Mills participants are delivered a highly motivating, effective and safe workout experience time after time.

Les Mills fitness programs are scientifically proven to deliver results. Check out some of our key research projects to find out the details. 


Les Mills BORN TO MOVE™ was created with a specific goal in mind, to get young people moving. By combining age appropriate music and movement we set out to inspire and motivate new generations and help them enjoy the increased self-esteem, wellbeing and health benefits of an active life. The BORN TO MOVE™ classes are underpinned by scientific research*, which shows that improved levels of fitness result in healthier, happier and smarter children.


Les Mills has conducted research measuring the effectiveness of BORN TO MOVE™.

In a Pennsylvania State University study two groups of children, aged 6-8years and 9-12 years completed two BORN TO MOVE™ classes a week for six weeks. In addition, the University of Auckland carried out research on BORN TO MOVE™ with children aged between 12-13 years.


Young people love the classes. Results of both studies revealed the participants experienced high levels of enjoyment and that the music and group environment were key drivers of this.

The classes improve attitudes to being active. The energy expended during a BORN TO MOVE™ class was equivalent to moderate intensity exercise and the classes had a positive effect on student’s self-efficacy to be active.

Parents recommend BORN TO MOVE™. Parents also had an extremely positive perception of the programs – 100% said they would recommend the classes to others.

You can find out more about these studies here.

*This research includes: Evidence that Aerobic Fitness Is More Salient than Weight Status in Predicting Standardized Math and Reading Outcomes in Fourth- through Eighth-Grade Students. Robert R. Rauner, MD, MPH1, Ryan W. Walters, MS2, Marybell Avery, PhD3, and Teresa J. Wanser, MA3. THE JOURNAL OF PEDIATRICS _ Vol. 163, No. 2 Physical Activity and Sedentary Behaviors and Health-Related Quality of Life in Adolescents Bamini Gopinath. PEDIATRICS Volume 130, Number 1, July 2012


Les Mills’ passion for supporting all-around healthy lifestyles has led to the development of the LES MILLS™ Food Pyramid and the LES MILLS™ 21 Day Challenge, a reduced carb diet that helps you reset your habitual eating patterns using a three week period to detox the body and provides eating habits that enable you to start fresh with more conscious behaviours around food.

The LES MILLS™ Food Pyramid and LES MILLS™ 21 Day Challenge have been developed by Dr Jackie Mills and Corey Baird. Jackie, who was originally an obstetrician and general medical practitioner, is a specialist in nutritional medicine, and has repeatedly seen the effects that great nutrition has on people’s health and vitality. Corey has a Diploma in Personal Training and is a certified CHEK Practitioner (Level 2), a certified CHEK Holistic Lifestyle Coach (Level 2) and a certified BioSignature modulation practitioner. Penn State University has conducted a literature review on the safety and efficacy of low carbohydrate diets. You can find a copy of the full literature review  here.

For more information about the Les Mills Food Pyramid, Les Mills 21 Day Challenge and frequently asked nutrition questions click here.

Get Fit Together

The 2011 Get Fit Together research proves that LES MILLS™ fitness programs work just as well as, if not better than, other exercise prescriptions.

Conducted in conjunction with Dr Jinger Gottschall and Pennsylvania State University, the Get Fit Together research tested the LES MILLS™ fitness programs using the American College of Sports Medicine physical activity guidelines. The Get Fit Together research provided:

  • An exact measure of the physiological, musculoskeletal and psychological benefits that beginners experience when they are introduced to a combination of Les Mills programs. 
  • An insight into how new participants feel as they progress through the different stages of the programs.
  • A proven approach for introducing new people to the classes and getting them hooked.

Check out this video for further details about the Get Fit Together research.

Read the full research paper here

LES MILLS GRIT™SERIES: High-intensity interval training that gets results

With an intense, scientifically-backed structure, the latest motivational music and highly trained coaches, LES MILLS GRIT™SERIES gets results – and a recent research project by Les Mills, Dr Jinger Gottschall at the Pennsylvania State University proves it. Designed to establish if the LES MILLS GRIT™SERIES could improve the health and fitness of already fit adults, this study measured aerobic fitness, body composition, functional strength and blood markers. After six weeks of testing participants’ improvement in health risk factors was better than from other forms of exercise.

Find out more about LES MILLS GRIT™SERIES and how why it works

Get a summary of the research here

When Les Mills set out to develop a team training program that would get real results we needed to make sure that embracing the fundamentals of high-intensity interval training was the way to go. Working with the AUT University Sports Performance Research Institute of New Zealand we were able to identify that high-intensity interval training is scientifically proven to improve fitness faster than conventional training methods.

Get the AUT research paper here

BODYPUMP™: the proven formula to transform your body


Over the last 10 years, Les Mills has conducted extensive independent research into the scientific benefits of BODYPUMP™. This research has confirmed that BODYPUMP™ has strong calorie and fat-burning effects and it improves aerobic fitness, muscular strength, and muscular endurance. There is also proof that BODYPUMP™ classes can have positive psychological benefits.

The secret to BODYPUMP™ is THE REP EFFECT™, a breakthrough in resistance training. THE REP EFFECT™ exhausts muscles using light weights, while performing high repetitions. Performing 800 reps in a single group workout, it’s more than four times the amount a person can achieve when training alone! BODYPUMP™ really is the fastest way to get in shape!

Find out more about the REP EFFECT™

Find out more about BODYPUMP™


Recent research conducted by Dr Jinger Gottschall and Pennsylvania State University has scientifically proven that integrated exercises deliver the fastest, most effective way to work your core. This research, which throws out traditional theories about core training, has been pivotal in the development of Les Mills CXWORX™.

Check out the below video for further details about the research behind CXWORX™.

Check out the abstract here.

Find out more about CXWORX™