HIIT and Other Interval Training Methods for Fat Loss

Written by Robert Forney ISSA CFT

Are you looking to lose fat without losing precious muscle mass? Are you looking for the best method of fat loss? Do you want to lose fat as quickly as possible? If so, your looking for HIIT training! HIIT training, which stands for High Intensity Interval Training, is one of the best training methods for fat loss and muscle retention. It also a preferred training program for fat loss because you can expend a lot of calories training for only 10 to 15 minutes a day! For those who have little time to train, this is the perfect training solution. HIIT training is not a new training technique. In the truest sense, it's nothing more than a form of interval training which has been used by coaches for many years. 

HIIT training is hands down the best way to lose fat without causing the body to catabolize muscle tissue. Studies have shown long endurance activates, such as marathon running, can cause muscle catabolism (the breakdown and loss of muscle tissue), which can last for up to 7 days after the activity takes place. On the other hand, HIIT training, will allow you to metabolize fat without losing precious muscle mass. Who wants to spend so much time in the gym building muscle mass only to lose it when performing cardio? If you need proof that HIIT training is a good form of training for fat loss and muscle retention, google for images of sprinters and take a look at how they look. You will quickly notice how lean and muscular they are.

HIIT (High Intensity Interval Training) and interval training are very similar, the only difference is the intensity in which they are performed. So what is interval training? Interval training is a varying of intensities within one workout, where you add a low intensity bout with a higher intensity bout. HIIT training is a very high intensity bout with a lower intensity bout.

You can perform your interval training in many ways, and you should use variety to keep it interesting. You can perform it on a stationary bike, stairmaster, mountain bike, local track, with weights, etc. Change it up often.

I will give you some ways of performing HIIT and interval training depending on your level of fitness. For the sake of simplicity, I will use running and jogging variations that can be performed almost anywhere.

stationary bike for HIIT training High Intensity Interval Training

The stationary bike is a great way to perform High Intensity Interval Training since it's safe and there is no risk of falling.

Interval Training for Beginners: If you are new to exercising you should start out slow. I will give you a few examples, but don't be afraid to experiment and find your own ways of creating an interval training program.

A good beginners interval training program is the walk-jog interval training. Start out with a 1 minute walk / 1 minute jog session and repeat for as many times as possible. As you progress, you can use a 30/30 routine where you walk for 30 seconds and the jog for 30 seconds. You can perform this anywhere. If you would like to make it a little harder, find some hills where you can perform it. Perform this routine from 2 to 4 times a week or more until you are able to progress to the intermediate level.

Intermediate Interval Training Program If you have been exercising for about 6 months, or are healthy and fit, then you can try some intermediate interval training. A good intermediate interval training program could consist of a jog-run program. You can warm-up with a five minute jog and then run for 1 minute, and then back to jogging for 1 minute, and repeat for as many times as you can. When you run, you don't need to sprint, but a good run is what you are looking for. If you want to add more intensity you can do a 30/30 split of a 30 second jog and a 30 second run. Or a 30 second jog and a 1 minute run. Perform this training 3 to 5 times a week for 10 - 20 minutes.

Advanced Interval Training Program (HIIT) Be warned, this is a tough routine! This is how I suggest you perform your HIIT training. There are many variations of it, but I will show you ways I perform it. Remember, it has to be intense to get the most of out it. You should be extremely tired when you are done. If you find you are able to perform it for 20 minutes on your first try and your not an elite athlete, you are not performing it with enough intensity. If you are ready for the advanced interval training, or HIIT, then this is the program for you.

Perform a 5 minute warm-up and then perform an all out sprint for as long as you can and then back to a jog for 1 minute and than another sprint, repeat for as many times a possible. At first you will be lucky to get past 5 minutes total after the warm-up. You can also perform a 30 second jog and all out sprint to increase the intensity.

To really increase the intensity, find some hills. I find it better to perform this on a stationary bike or Stairmaster when you first start since there is less risk of injury due to falling. Some other variations would be to perform the all out sprint and than back to a jog again until you are ready to perform another sprint. Although not as intense as the other ways, it is a good way to get used to the program. Perform this training 3 to 5 times a week, for 5 to 20 minutes depending on your ability.

Variation As with all training, you should add variety to your interval training as you would with any type of training. You should change it every 4 to 6 weeks in order to keep it fresh. Some good ways to add variety is to change the times, or perform your training on a bike, stairs, hills, stationary bike, Stairmaster etc. One of my favorite ways is on a stationary bike where I can increase the intensity during the all out portion of the interval training. Don't be afraid to create your own types of interval training to suit your own likes and dislikes. Have fun with it and the fat will come off.

Concluding Remarks Interval training is a fun and great way to lose the fat and increase your general physical preparation. Remember to start out slow if you are new to exercising. When you are ready, advance to the HIIT style. Here is another quick article you may be interested in reading:


James Krieger

As exercise intensity increases, the proportion of fat utilized as an energy substrate decreases, while the proportion of carbohydrates utilized increases (5). The rate of fatty acid mobilization from adipose tissue also declines with increasing exercise intensity (5). This had led to the common recommendation that low- to moderate-intensity, long duration endurance exercise is the most beneficial for fat loss (15). However, this belief does not take into consideration what happens during the post-exercise recovery period; total daily energy expenditure is more important for fat loss than the predominant fuel utilized during exercise (5). This is supported by research showing no significant difference in body fat loss between high-intensity and low-intensity submaximal, continuous exercise when total energy expenditure per exercise session is equated (2,7,9). Research by Hickson et al (11) further supports the notion that the predominant fuel substrate used during exercise does not play a role in fat loss; rats engaged in a high-intensity sprint training protocol achieved significant reductions in body fat, despite the fact that sprint training relies almost completely on carbohydrates as a fuel source.

Some research suggests that high-intensity exercise is more beneficial for fat loss than low- and moderate-intensity exercise (3,18,23,24). Pacheco-Sanchez et al (18) found a more pronounced fat loss in rats that exercised at a high intensity as compared to rats that exercised at a low intensity, despite both groups performing an equivalent amount of work. Bryner et al (3) found a significant loss in body fat in a group that exercised at a high intensity of 80-90% of maximum heart rate, while no significant change in body fat was found in the lower intensity group which exercised at 60-70% of maximum heart rate; no significant difference in total work existed between groups. An epidemiological study (24) found that individuals who regularly engaged in high-intensity exercise had lower skinfold thicknesses and waist-to-hip ratios (WHRs) than individuals who participated in exercise of lower intensities. After a covariance analysis was performed to remove the effect of total energy expenditure on skinfolds and WHRs, a significant difference remained between people who performed high-intensity exercise and people who performed lower-intensity exercise.

Tremblay et al (23) performed the most notable study which demonstrates that high-intensity exercise, specifically intermittent, supramaximal exercise, is the most optimal for fat loss. Subjects engaged in either an endurance training (ET) program for 20 weeks or a high-intensity intermittent-training (HIIT) program for 15 weeks. The mean estimated energy cost of the ET protocol was 120.4 MJ, while the mean estimated energy cost of the HIIT protocol was 57.9 MJ. The decrease in six subcutaneous skinfolds tended to be greater in the HIIT group than the ET group, despite the dramatically lower energy cost of training. When expressed on a per MJ basis, the HIIT group's reduction in skinfolds was nine times greater than the ET group.

A number of explanations exist for the greater amounts of fat loss achieved by HIIT. First, a large body of evidence shows that high-intensity protocols, notably intermittent protocols, result in significantly greater post-exercise energy expenditure and fat utilization than low- or moderate-intensity protocols (1,4,8,14,19,21,25). Other research has found significantly elevated blood free-fatty-acid (FFA) concentrations or increased utilization of fat during recovery from resistance training (which is a form of HIIT) (16,17). Rasmussen et al (20) found higher exercise intensity resulted in greater acetyl-CoA carboxylase (ACC) inactivation, which would result in greater FFA oxidation after exercise since ACC is an inhibitor of FFA oxidation. Tremblay et al (23) found HIIT to significantly increase muscle 3-hydroxyacyl coenzyme A dehydrogenase activity (a marker of the activity of b oxidation) over ET. Finally, a number of studies have found high-intensity exercise to suppress appetite more than lower intensities (6,12,13,22) and reduce saturated fat intake (3).

Overall, the evidence suggests that HIIT is the most efficient method for achieving fat loss. However, HIIT carries a greater risk of injury and is physically and psychologically demanding (10), making low- and moderate-intensity, continuous exercise the best choice for individuals that are unmotivated or contraindicated for high-intensity exercise.


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