In summary, if you're only interested in a basic understanding of HIT methodology and where much of it originated I would suggest starting with a far less technical book. I suggest starting with the last published edition of Ellington Darden's "The Nautilus Book" and perhaps "Total Fitness: The Nautilus Way". If you like what you read and want to dig a little deeper into the evolution of HIT read Darden's more recent book, "The New High Intensity Training: The Best Muscle-Building System You've Never Tried". If the gears in your head are in high gear after that and you really want to get DEEP into what evolved from the original Nautilus protocol _then_ you go for "Superslow" or preferably "The Renaissance of Exercise: A Vitruvian Adventure Volume 1". When your grasp of all the aforementioned material is truly solid then move on to Doug McGuff's writing. McGuff's ideas do not surpass or supplant Hutchins' but rather sharpen the points with brilliant thoughts and clinical observations from a medical physician's perspective. Doug McGuff, MD published his "Ultimate Exercise: Bulletin #1" in the late 90's and later updated that with "Body by Science: A Research Based Program to Get the Results You Want in 12 Minutes a Week", both of which are hugely valuable contributions to the literature on HIT methodology and philosophy. His article about "Stoicism in Training" is critical reading.
Flexibility exercise, or stretching, is a vital component of any exercise regimen. The primary purpose of flexibility training is to increase your range of motion, especially when it comes to muscles and joints. Although flexibility exercise will not improve your endurance or strength as cardio or anaerobic exercise would, flexibility training helps your body maintain its natural alignment. By doing so, flexibility exercise makes your body significantly less prone to injury during cardio or anaerobic exercise. Additionally, practicing flexibility training will increase your freedom of movement in a way that makes everyday activities easier. Tasks such as reaching up for an object on a shelf, getting up from a chair, or even sitting in confined spaces for long periods of time will greatly benefit from flexibility training.
The hypothalamus is under the control of several “higher” brain centres and several neurotransmitters 13 known to play a major role in various neuroendocrine and behavioural functions, for example, activation of the HPA axis, feeding and locomotion.14 Therefore, the typical HPA axisrelated hormones cortisol, adrenocorticotrophic hormone (ACTH), prolactin (PRL) and human growth hormone (GH) were targeted in the present study.
Bottom line. Muscle confusion is a snappy term for non-linear periodization, which simply means rotating the workouts you do so that your muscles are constantly challenged and you get better, faster toning and weight-loss results. Research suggests this approach is more effective than doing the same exercise routine. P90X is a 90-day plan that combines strength moves, cardio, and yoga—and if you follow it faithfully, you will probably see results. But it’s suitable only for those who are already very fit because the routines are intense and take about an hour a day. Note: You’ll also need dumbbells, exercise bands, and a pull-up bar, which do not come with the basic system. The diet is complicated, but it provides an appropriate number of calories for the work you’ll be doing.