CARDIO

[C]

HIGH 

INTENSITY

INTERVAL 

CARDIO

W

e all know that one person who is a fixture on the treadmill or elliptical trainer – 
every time you come to the gym, there they are, working away at monotonous 

high-duration cardio to burn body fat. But what they’re really doing is breaking down their 
muscle and burning very little fat.
Studies show that type of cardio isn’t as beneficial for fat loss as experts once thought, 
and even worse, it can be detrimental to body composition. 
High-Intensity Interval Training (HIIT), sometimes referred to as High-Intensity 
Intermittent Exercise (HIIE) is the best prescription for fat loss. 
When it comes to fat loss you want to burn at as high a rate as possible right? HIIT 
accomplishes this through intervals that push heart rate to the brink, then back it off to a 
moderate pace, and resume a higher intensity again at the end.
The best part is, with HIIT you're burning more calories and fat, but for a much shorter 
time than the old school cardio method. Shorter, more intense, sessions for cardio mean 
optimal fat loss and maximum muscle retention – which has always been a necessary 
evil for the kind of aerobic training that's always been done for competitions.
With HIIT, you don’t have to do hours of cardio because your workouts are going to 
actually be more intense and more difficult than the guy working three times as long on 
the treadmill next to you.

For bodybuilders and others trying to 

hang on to hard-earned muscle, the old 

steady-state cardio, with low to moderate 

intensity levels, are no longer the norm.  In 

fact, exercise performed at 60 to 70 percent 

of one’s maximum heart rate (MHR), 

whittles away not only body fat but muscle 

too.  HIIT cardio, on the other hand, uses 

short intervals of high-intensity exercise to 

peak your heart rate at 90% of your max, 

but, followed immediately by intervals of a 

slower recovery to a more normal heart rate. 

HIIT should be considered the only way 

to truly lose body fat fast, while increasing 

heart health and retaining muscle. 

THE PROTOCOL

Typical HIIT sessions vary, but run 

anywhere from 10 to 20 minutes, depending 

upon your level of fitness. Don’t be 

surprised, even if you’re a seasoned cardio 

guy or girl, if you are not up to the HIIT 

challenge at first. It’s a gut and lung buster, 

and is challenging for people of all fitness 

levels.  

But however grueling it may be, it is 

proven to increase athletic capacity, and 

improve condition, and glucose metabolism, 

as well as burning more body fat than 

steady-state cardio at low to moderate 

intensity.

One of the reasons HIIT is more effective 

in 20 minutes than standard cardio in 60 

minutes, is that HIIT training causes your 

body to produce more fat-burning hormones 

(hGH) through working more than one fiber 

type. Whereas running may work one type, 

and cycling may work another, HIIT works 

three types:

TRAINING GUIDE  

PRIMAL MUSCLE  19