The study was small, on just 10 men who spent two periods of 24 hours each in a specially designed metabolic chamber, but it showed amazing results. During one period they did nothing but eat two meals. During the second period they did nothing, with the exception of riding a stationary bike at high intensity for 45 minutes.
The exercise itself burned about 420 calories, but over the next 14 hours, the men burned an extra 190 calories. The New York Times reported:
"We were surprised," the study author said. "She thought there might be extra calories burned, but she did not expect so many, nor did she expect the effect to last so long."
Very vigorous, high-intensity exercise is also the type that can help your body increase production of human growth hormone (HGH). HGH is naturally produced by your body in sufficient quantities until you reach the age of 21. After this, production starts to drop.
HGH is the master hormone controlling growth. It helps build muscles, bones, organs and the basic links between the cells. Lower levels of HGH also make it more difficult to lose weight -- HGH increases your metabolism, which helps to burn more fat.
According to Fitness Health Zone:
"Thus a person loses weight but not their body muscle. It also helps to increase the levels of HDL the good cholesterol, thus reducing cardiovascular risks too."
Regular exercise should not be viewed as an afterthought or something you "get to" if you can "find the time." Not if you want to be truly healthy. Exercise is simply too important and crucial to miss.
Remember that if you are NOT yet exercising on a very regular basis, you are missing out on one of the most effective tools known to produce radical health improvements. Even initiated late in life, exercise can help slow down the aging process altogether, so you'll be less likely to suffer from chronic disease or disability, and more likely to be fit and trim, agile, mobile and happy.
What's not to like?
New Research Confirms Exercise Intensity Matters
It's true, of course, that exercise is hard work. In fact we now know that while there are some benefits from mild exercises like walking the vast majority of the improvements are related to your pushing yourself to failure. This is where the
"magic" of exercise truly occurs. The beauty of pushing yourself this hard though is you only need to exercise for a small fraction of the time as when exercising less intensely.
If you simply head outside for a walk, meander around the block once or twice and call it a day, or use a very light set of weights and merely go through the motions, it is certainly better than doing nothing … but you will not be challenging your body enough to reap the full potential benefits that exercise has to offer (unless you are very out of shape to begin with, in which case walking is an excellent starting point).
For instance, take the new study published in Medicine & Science in Sports & Exercise. When study participants exercised at high intensity for 45 minutes, they not only burned 420 calories during their workout, they also burned an additional 190 calories over the next 14 hours; that's a 37 percent increase in total calories burned.
Now, here's the kicker: the men in the study exercised at 70 percent of their VO2 max, which is the maximum amount of oxygen you can take in while exercising. Exercising at this level is far below the intensity of Sprint 8 exercises, which I'll describe below, but it does mean that you are breathing too hard to carry on a conversation.
This really is a great guide as if you can carry on a comfortable conversation while you are working out (at least for your high-intensity periods), odds are very good that you aren't pushing hard enough.
As the New York Times reported, in a separate but similar study, the participants exercised at 50 percent of their VO2 max, which is at a level that allows you to carry on a conversation -- and did NOT burn any additional calories after their workout. So this means that if you want to burn bonus calories after you exercise, you must exercise intensely enough -- at upwards of 70 percent of your maximum exertion level.
And it appears that the harder you exercise, the more calories you'll burn after you work out.
The Only Type of Exercise to Increase Human Growth Hormone
Vigorous high-intensity exercise like Sprint 8 is not only required if you want to keep burning calories after you exercise, it's also the only type of exercise that leads to increased production of HGH.
Unlike the exercise done in the study above, which used 70% of VO2 Max, Sprint 8 is done at a higher intensity that approaches 100% of VO2 Max but only for 30 seconds. That is the magic. Unlike the 45-minute workout above, Sprint 8 is done in less than half the time and will likely provide more than twice the benefit when performed properly.
I recently ran an interview with fitness expert Phil Campbell, in which he further expounds on this important topic.Phil is the author of the book Ready Set Go, which explains how exercises that engage your super-fast muscle fibers can increase your HGH levels.
I had the great pleasure of meeting Phil at a fitness camp in Cancun, Mexico last year, and he taught me how to apply this high-intensity exercise technique. It has literally transformed my physique and physical health the way no other form of exercise ever has, and I'm confident it can likely do the same for you.
Human Growth Hormone (HGH) is one of the reasons that explains why this approach is so effective. Remember many athletes spend thousands of dollars every month to inject HGH to improve their performance. Not only is this unnecessary but it will contribute to health problems because it is impossible to get the HGH dose correct. Only your body knows what you need and has the feedback loops to optimize your levels.
Plus it is basically free. The only cost is your time. You save yourself well over ten thousand dollars per year if you don't purchase HGH injections.
If you're over the age of 30, especially if you lead an increasingly sedentary lifestyle, you've likely entered a phase known as somatopause (age-related growth hormone deficiency). As your HGH levels decrease, your levels of insulin-like growth factor-1 (IGF-1) also decrease, which is an important part of what drives your body's aging process.
When you perform Sprint 8 exercises properly it helps increase your HGH, which increases your muscle growth and effectively burns excessive fat. It also plays an important part in promoting your overall health and longevity.
According to a study published in 2008, the two interventions most consistently associated with increased lifespan in animal models are caloric restriction and repression of the HGH/IGF-1/insulin axis.
The authors explained:
"In humans as well as other species, a reduction in the GH/IGF-1 axis is correlated with increased percentage of total body and visceral fat, decreased muscle mass, decreased physical fitness, decreased immune function, and physiological declines in estrogen and androgen concentrations.
Thus, the natural declines in GH and IGF-1 that accompanies age-related degenerative processes implies that the GH/IGF-1 axis may be a causative determinant."
Why High-Intensity Exercises are Necessary for HGH Production
In order to boost HGH, you need to exercise your super-fast muscle fibers, as the super-fast muscles are the muscle fibers that have major impact on your production of HGH. It's important to understand that neither traditionally performed aerobic cardio nor typical strength training will work anything but your slow muscle fibers.
As one study, published in 2003, found:
"An exercise intensity above lactate threshold and for a minimum of 10 minutes appears to elicit the greatest stimulus to the secretion of HGH."
As you will see later, this is exactly what you do when performing Sprint 8 exercises. If performed correctly, meaning intensely enough, you'll feel that muscle "burn," which is a sign of lactic acid being released.
Another study published in 2002 also found that there's a "linear relationship between the magnitude of the acute increase in growth hormone release and exercise intensity."
In young women, "chronic aerobic training at an intensity greater than the lactate threshold resulted in a 2-fold increase in the growth hormone released over a 24-hour period."
Update on Growth Hormone (GH) Production
It was my previous understanding that the super-fast muscle fibers (type II B) were the only fibers that trigger GH release. This does not appear to be the case. In fact, it's the fast type II A that has the strongest effect on GH by virtue of its special durability. It's the only fiber that allows you to sustain intense exercise for minutes at a time.
Ori Hoffmeckler has provided the following update to more clearly explain this new understanding of how GH is produced by your muscle fibers.
There are additional advantages of the short-intense exercise protocol including:
- Improving muscle fiber quality
- Increasing mitochondrial density
- Increasing glycozin load capacity
- Increasing muscle work output
- Reversing age-related neuro-motor deterioration
- Preventing age-related loss of fast muscle fibers
- Increased muscle mass
The point is: the short intense training protocol improves muscle energy utilization and expenditure due to its positive effects on increasing muscle mass and improving fiber quality. Note that muscle tissue burns 3-5 times more energy than fat tissues. This means that muscle gain increases the body's metabolic rate.
Also, fast muscle fibers burn 2-3 times more energy than slow muscle fibers. And this means that improved muscle fiber quality is a metabolic boosting trait by itself.
But here is the catch:
The super-fast muscle fiber type II B is limited to carb fuel only. It can hardly utilize fat fuel. And studies showed that people with predominately high percentage of type II B muscle fibers are more prone to suffer from obesity, diabetes, and cardiovascular disease.
Yes, the inability of the super-fast muscle fiber to utilize fat fuel is a liability!
That's unlike the fast type II A muscle fiber, which can effectively utilize both carb and fat fuel. So it's the fast type II A muscle fiber (not the super-fast type II B fiber) that enables you to burn fat and build a lean, strong and durable physique.
There is serious confusion regarding the animal studies and the HGH/IGF-1 insulin axis. Apparently in animals high IGF-1 has been shown to shorten life span. In humans IGF-1 has been shown to actually INCREASE life span. So that understanding needs to be corrected.
Sprint 8: A Simple High-Intensity Exercise Virtually Everyone Can Do
Exercising at high-intensity is not as intimidating as it first might sound. With Sprint 8 exercises you can perform them with any type of exercise -- walking, jogging, biking, elliptical machine, you name it -- and in just 20 minutes.
Although I had initially recommended the recumbent bike for Sprint 8, my new favorite is the elliptical machine in which you can also use your arms. I typically put the resistance at zero for rest intervals and speed is 1 to 2 mph but for the Sprint 8, I increase the intensity to a bit less than half and run at about 3;30 mile pace or 16 mph for 30 seconds.
Instead of doing an hour-long cardio workout, you'll be done in 20 minutes or so.
The actual high-intensity portion totals only 4 minutes! And, in fact, you should only do Sprint 8 exercises no more than three times a week, as if you do it more frequently than that you may actually do more harm than good.
Phil Campbell agrees, and also warns against overdoing it. We've found that, more often than not, when people do it more than four times a week they're simply not pushing themselves hard enough when they're doing the Sprint 8 exercises.
More is NOT better here. It is very easy to overdo it.
In fact once you reach your fitness goals and have your lean body mass optimized I suspect you can get by with only one Sprint 8 every 7-10 days. But the key will be to REALLY push yourself on the day that you do your Sprint 8.
The key to performing Sprint 8 exercises properly is to raise your heart rate up to your anaerobic threshold. Keep pushing at maximum effort for 30 seconds, and then rest for 90 seconds. Repeat this cycle for a total of eight repetitions. In other words:
- Warm up for three minutes
- Exercise as hard and fast as you can for 30 seconds. You should be gasping for breath and feel like you couldn't possibly go on another few seconds
- Recover for 90 seconds, still pedaling, but at slower pace and decreased resistance
- Repeat the high intensity exercise and recovery 7 more times
In the video below, Phil Campbell and I demonstrate how it's done.
Remember, Sprint 8 is only one part of an overall fitness program, but it is a part you do NOT want to miss. With ordinary cardio you will stop burning calories when you stop exercising, and you will not get the added benefits of increased HGH production.
With Sprint 8, you'll burn extra calories for hours after your workout and will also boost your HGH levels.
Remember, you only need to do Sprint 8 exercises for 20 minutes, twoand at most three times a week. As your fitness level improves you can reduce the frequency but NOT the intensity. Never reduce the intensity or you will lose the effects, which include:
- Decrease in body fat
- Improved muscle tone
- Firmer skin and reduces wrinkles
- Increase in energy and sexual desire
- Improved athletic speed and performance
- Slowing down the aging process and telomere shortening
Surely, with results like these, you can find time for that!