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What is HIIT Training?

aerobic exercise

HIIT is defined as repeated bouts of exercise at maximal intensity; that reflects the client’s VO2 max peak with active rest intervals in between. The maximal intensity bouts of exercise and active rest intervals can be manipulated to suit the fitness levels of the individual, as the fitter they are; the shorter the active rest intervals and the longer the blasts of activity are (see table below).

Cardio HIIT training should only be used with clients at the lower end to middle of the spectrum of the special population. Do try to build a bit of high-intensity work into the exercise programs. Throughout this manual, there will be some good examples of HIIT used in the sample workouts at the end of each section.

aerobic exercise

Green zone is for an advanced fitness level and there is a 1:3 ratio of work intervals versus active rest intervals.

Amber zone is for an intermediate fitness level and there is a 1:2 ratio of work intervals versus active rest intervals.

The Red zone is for a beginner fitness level and there is a 1:1 ratio of work intervals versus active rest intervals.

Research has indicated that to get the best results in HIIT training; they should be between 12- 15 minutes in duration with an exercise frequency of no more than twice a week (this will need careful monitoring with the client).

Conventional cardio programs dictate that for the best fat burning results, a client should be exercising at 65% of their heart rate maximum for between 30-50 minutes, at least 5 times per week. This is a training myth. This time consuming conventional approach is detrimental to muscle gain and does not shed as much fat as HIIT training.

The question is why?

Conventional cardio has the following adverse effects on muscle growth and is very much catabolic in terms of muscle growth:

  • It breaks down the muscle tissue.
  • Decreases testosterone levels in the body.
  • A decrease in glucose absorption after training.
  • Blocks the motor pathway which is important for muscle growth.

On the other hand, research has indicated that HIIT training increases the muscular oxidative capacity of the mitochondrial enzymes, increases testosterone levels, raises Glut 4 levels and increases the myofibril cell size. All of these factors are all hugely important in gaining muscle size and mass.  After a HIIT session, there is evidence to suggest that human growth hormone is increased by 450% and this important catalyst is extremely important for muscle growth. Also, insulin sensitivity is enhanced; which translates to glucose entering into the muscle instead of being stored as fat and carbohydrate metabolism is more efficient post exercise.

Due to the higher intensity of the work intervals being performed for a longer duration than during a steady state protocol; there is a higher amount of fat being shredded.  This fat shredding also occurs up to 24 hours post-exercise and is this process is called the ‘excess post-exercise oxygen consumption’  (EPOC)  or the ‘afterburn effect’.

However, this fat burn burning mechanism is not evident in conventional cardio. HIIT training improves aerobic capacity, enhances glycogen utilization, and the lactate threshold is raised so that you can train for longer periods, and subsequently burn more body fat.

It has been established that HIIT training helps to shred fat, improves muscle tone, aids with muscle size/mass and greatly improves cardiovascular function. Here are some other key benefits:

  • It can be performed anaerobically with weights and aerobically while performing cardio.
  • It can be performed outside or in the gym.
  • It uses a variety of exercise machines such as treadmill, elliptical machines, and bike.
  • It can be manipulated using different exercise modes such as running, sprinting, jumping, skipping, plyometrics, Tabata protocol, and calisthenics.

Now What?

The latest research proves that metabolic conditioning training and HIIT are among the fastest ways to reach your fitness, health, athletic and weight loss goals. Most of your client’s goals are to burn fat, build muscle and get into amazing shape. And they rely on you to get them there. Science and research prove that metabolic training is the fastest way to get these results.

The Metabolic Conditioning Coach course is specifically designed to teach you the specific method of metabolic training. You will be giving the framework around this method of training and from there you will be able to put it into action.

Check out what it takes to start a career in personal training. This is your most affordable and fastest way to become a highly qualified personal trainer.

There is always something exciting about earning a new coaching or training certification and applying that new knowledge of how you train your clients. This also helps you hit the reset button.

NESTA certification programs are open to anyone with a desire to learn and help others. There are no prerequisites.

That’s it for now.

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