This is a concise book about High Intensity Interval Training (HIIT). What it is about, why it is beneficial for our body, the history of its discovery, the legends on the field, and most importantly the many different types of HIIT exercises and how to practice them. The lead author, Martin Gibala PhD, is obsessed with the scientific approach on physiology and it is clearly shown in the multiple experiments, the data-heavy findings, and the overall science-based narrative of the book.
Using running as the main focus, through multiple studies Gibala concludes that in a much shorter time frame sprint interval training is just as effective as long distance work (in a slow to moderate pace) for increasing the main predictor of aerobic fitness and longevity: VO2 Max. Gibala explains, “approximately ten minutes of hard exercise a week boosted overall fitness to the same extent as four and a half hours per week of traditional endurance training. It’s mind-blowing. A tiny bit of sprint training has the same effect on the human body as a whole lot of endurance training—despite a much lower training volume and time commitment.”
To illustrate this with a training term, using 3 x 20-second sprints over a 10-minute window (3 times a week) can generate the same impact to cardiorespiratory fitness, mitochondrial density, body fat percentage, and management of blood sugar as 3 x 50 minutes of moderate-intensity runs. That’s 30 minutes vs 150 minutes a week effort with the same benefits. Even interval walking (walking at a normal speed for 3 minutes, then at a faster speed for 3 minutes, then back to normal speed, etc) will generate “more improvements in cardiorespiratory fitness and much larger decreases in blood pressure for those who are out of shape” compared with a regular steady speed of walking.
Moreover, as with any other fitness books, Gibala also provides all the good nutritional checklist and methods that can perfectly supplement high intensity training. It has all the usual suspects, such as intermittent fasting, cutting sugar, the importance of eating more protein in every meal, while restricting our food intake using calorie counting, and drinking only water and not drinking our calories (not even sports drink).
The theory is not without a flaw, however, as the HIIT approach is not readily suitable for everyone. The book provides a careful analysis on many different types of body and capabilities, including people with heart disease, couch potato and people at the age of 50, 60, 70 and above, and provides the more suitable high intensity training for them. Gibala also took a great length for addressing, and solving the problems of, the so-called “noneresponse”, that is those people whose body do not respond to diet and exercise changes, where some even become less fit after exercising.
But for the rest of us, the 12 different HIIT training styles that are guided in the book are relatively simple and easy to follow, which is astonishing considering the complicated science behind them and the obvious benefits that look too good to be true at first, but almost instantly impactful when I tried it myself: It solved the mysterious stagnation in my running performance this year, which was baffling for me because I thought I did a good progress by keep increasing the mileage of the same 3x weekly runs.
But after reading this book (over twice the time I normally read books, so that I can practice them more accurately), I hit that “oh shit!” moment.
As it turns out my previous years’ improvement streak partly got to do with luck, as before the pandemic I used to play football and tennis every week alongside my weekly runs at moderate intensity, two sports that require burst of sprint – walk – sprint – walk (aka speed play). Last year when Covid hits I stopped playing them, but my physical improvement continued simply because I was following Jeff Galloway’s running method, that includes sprints / higher intensity pace. Meanwhile, starting from the beginning of this year I almost exclusively implement Matt Fitzgerald’s 80/20 run, 3x a week, with no other variation.
So, as you can probably see, for an autodidact running geek who loves to conduct my own trial and errors using many different theories, this book is definitely a game changer for me. One that explains the science behind the reason why the best of the best coaches in the world all put a great emphasis on the fartlek (or speed play) training and hill training among their weekly training schedule. One that inspires me to plan a more efficient training schedule and insert fartlek and interval walking in between my 80/20 runs.
And as a result, after a brief slump, my VO2 Max level is now back to before the pandemic level.