Effect of HIIT Training on Body Fat Mass and Visceral Fat Mass

· Body Composition

High intensity interval training, or HIIT, is sold at gyms and fitness classes as the most efficient way to lose fat and build muscle for our time poor society. HIIT is, essentially, a workout in which bursts of high intensity cardio are alternated with short, low intensity exercises over a certain length of time1. Workouts can be anywhere between 5 and 45 minutes.   

Is HIIT the fastest way to lose fat? 

HIIT has been shown to be a highly effective way to lose both body and visceral fat mass2. While lower intensity training also reduces fat mass, the process is slower and studies show its effects are more concentrated in the abdominal region, helping you to shed visceral fat first. High intensity training at above 90% peak heart rate was effective for the whole body, removing both body fat mass and visceral fat mass.  

But what about running and cycling? 

Running and cycling are often performed as steady state exercises, which in one study3 was shown to be less effective than resistance and HIIT training at increasing the number of calories burned over the post exercise period. In terms of numbers of calories burned over a workout, the same study recorded that steady state, resistance and HIIT burned about the same amount over a 40-45-minute period.  

You can make running and cycling high intensity – one study4 confirmed that high intensity intermittent (interval) cycling was more effective at burning fat than a lower intensity. If running or cycling is your thing, make at least one workout a week a HIIT workout by performing intervals as hard as you can. 

Making sure HIIT works for you 

HIIT workouts are intense, and while you can do them without supervision – the internet has loads of great resources – many people opt to join a class or work with a personal trainer. Either way, HIIT is intense. Hold yourself accountable for sticking with your exercise and diet program. Personal accountability is essential for improvement. Since improvement is the reward for all that hard work, make sure you can see it! Every fortnight, take photos in your underwear and track the changes in your body composition. Body Exo’s Accuniq and our unique data visualisation software Stretch will allow you to see the increase in skeletal muscle mass and the drop in body and visceral fat.  

Tracking your body’s data 

A body composition scan is the most accurate and accessible way to track the improvements you’ve made to your body. A body composition scanner that sends multi-frequency electrical currents through your body, will be able to measure, the amount of body fat mass, visceral fat mass and skeletal muscle mass at that particular point in time with a high degree of accuracy. Photos and scans should be taken at the same time of day and point in your routine. This is so the body’s conditions – hydration and so on – are about the same each time. This ensures that the changes tracked are the ones you have made, not the ones that occur naturally in your body over a day.  

Capturing body composition data in combination with HIIT Training should not be a one-off event. Tracking your data, as a part of looking after your health, is an ongoing commitment to constant improvement. 

Reducing Body and Visceral Fat: HIIT’s Role in Community Health  

HIIT training has received much interest as awareness of the high rate of obesity and lack of mobility amongst the population has grown. In a society where many people lead very busy lives and struggle to meet recommended weight and exercise benchmarks, a time effective way to shed fat and stay mobile is essential for individual health as well as avoiding excessive burdens on the national healthcare system.  

BodyExo CEO Adrian Rainey suggests that fitness venues with the capability to collect data can support public health by contributing towards data collection. 

“Gyms that provide HIIT training must now support public health with body composition data, such as decreasing body fat mass and visceral fat at an aggregate level. This aligns to decreasing costs on the public health system along with decreasing the risks to lifestyle related diseases,” he said. 


[1] https://dictionary.cambridge.org/dictionary/english/hiit

[2] https://pubmed.ncbi.nlm.nih.gov/29127602/

[3] https://pubmed.ncbi.nlm.nih.gov/25675374/

[4] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4048667/