The beauty of H.I.I.T is not only better results with shorter time commitment, but the reason behind it. Any workout produces certain hormonal responses in the body. A few main hormones that are of importance when we talk about fat burning and growing muscles, are cortisol, growth hormone and testosterone. With longer workouts (even though they are less intense) the body gets too taxed, and after about 40-45 minutes cortisol levels rise pretty high. This has a catabolic (breaking down muscle) effect on the body rather than anabolic, as most exercisers desire. Growth hormone and testosterone, which stimulate muscle growth and fat burning, and are released in higher amounts as a result of exercise, get suppressed if the workout is too long and stressful on the body. However, shorter workouts, but with higher intensity, seem to create an ideal situation for a much lower cortisol release and, at the same time, no suppression of either growth hormone or testosterone. In fact, these two hormones seem to respond amazingly well to this kind of scenario. There may be many reasons behind it, the main one being that humans evolved to use high intensity movements only for short periods of time, as in “fight or flight” situations, and otherwise move a lot but in a low intensity fashion, and our bodies are simply better adapted to handle this kind of exercise on a hormonal level than workout sessions that are medium/medium-high intensity and last forever.
This video is designed for pretty advanced and experienced exercisers. Please, make sure to watch all the instructions carefully. The length of the H.I.I.T circuit can easily be adjusted to suit anyone with a limited amount of time, from as short as 3 minutes all the way to 30. You probably wouldn’t want to do just 3, but all the circuits in this series (there are 5) range from 2 ½ to 5 minutes. All you need to do is repeat them as many times as your endurance and level of conditioning will allow, up to a maximum of 30 minutes total. They will give you a great fat-burning full body workout, addressing most of the muscle groups. H.I.I.T is great for toning and shaping, as well as overall muscle conditioning. You don’t really need a lot of additional abdominal exercises since your core is used to a great degree in most of the exercises shown.
Please, always do a 5-10 minute warm-up before any exercise.
If you’re not used to working out at a very high intensity you may need between 1.5 to 2 minutes of rest before repeating each circuit. If you find that your level of fitness and conditioning allows you to move faster through the whole routine, then take only 1 full minute of rest between the circuits.
Each circuit consists of 5 exercises and all exercises are done in sets of 6 repetitions, using moderate weights that are still challenging, but that will also allow you to perform full range of motion and complicated multi-joint movements. You will have to figure out yourself what amount of weight you feel most comfortable with that will let you finish the whole set with good form. The sets are short since you are not resting at all during each circuit, and anything longer would be too taxing on the body given the choice of exercises.
Make sure that you get enough recovery between sessions. Most of the exercises in these videos are strenuous and demanding, and you will need a minimum of 48 hours recovery time. For many people a schedule of 2 days of rest afterwards is a better option to avoid overtraining.
DON’T LET THE LOOKS FOOL YOU. IF YOU DO THE EXERCISES CORRECTLY AND WITH A FULL RANGE OF MOTION, YOU CAN GET VERY SORE FROM THIS WORKOUT, SO BE SMART ABOUT PROGRESSION AND DON’T START WITH 7 OR 8 CIRCUITS, AS YOU WON’T BE ABLE TO MOVE THE FOLLOWING DAY.
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