Sprinting and Human Growth Hormone

As the name implies Human Growth Hormone, or HGH, is responsible for growth seen in children and young adults.  It's produced in the pituitary gland in a series of pulses, with about 75% being released while we sleep. When we stop growing taller, in our early 20s, the rate of production of HGH drops off rapidly.  By the time we reach middle age, our rate of HGH production is a tenth what it was when we were children.

Source: Mercola Fitness

Aside from making us grow when we're young, HGH is responsible for a lot of other beneficial affects on the body, including adding muscle and strengthening bones.  In adults, it also plays a role in improving cognition, reducing weight, improving skin, increased energy, and improving mood.  With effects like that, as the saying goes, it's a shame that youth is wasted on the young.

Sprinting and Human Growth Hormone Production

One key difference between moderate and high-intensity exercise is that when you reach your anaerobic limits, your pituitary gland releases starts pumping out HGH.  These HGH pulses are signals to the body that instigate a number of age-related bodily functions and the production of other hormones like DHEA and melatonin.

The most important of these signals causes by HGH, as far as finding the fountain of youth, is the one seen by the liver, which causes it to produce insulin-like growth factor (IGF-1).  The benefits of HGH in adults can be measured by how much IGF-1 is produced.  Anything over a 20% increase in production is considered to significant, as far as anti-aging is concerned.  And high-intensity exercise increases the production of IGF-1 by over 700% during the workout, and for several hours afterward.

Of course, you can't go out and sprint the same way you can when you go for a jog. Sprinting, and any high intensity exercise, has to be done in intervals, because they'll quickly deplete the amount of energy (in the form of ATP) available in your muscles.  Not to mention the fact that, if you're running at 90% of your maximum, you'll be left gasping for breath pretty quickly.  If you're just getting started, you may find it hard to run, really RUN, for longer than 15 seconds.

Instead of just going all out for 30 minutes, which isn't really possible anyway, you need to try working in intervals.  High Intensity Interval Training (HIIT) gives you the time to work at your maximum effort and then to recover, and go again.  Sprinterval helps you increase your work capacity over the course of a six week program. It's free, and available for iPhones and Android devices.

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Sprint Intervals and the Afterburn Effect

Sprint intervals, a form of High Intensity Interval Training - HIIT, are no joke.  Each interval may be short, but you're working at between 80-90% of your maximum effort, which means that in less than 20 minutes you'll be left gasping for breath.  Endorphins aside, it's not a great feeling.  But that gasping for breath actually has an incredibly positive side effect - EPOC, also called the afterburn effect.

What is EPOC?

Excessive Post-exercise Oxygen Consumption is the term given to your body's response after exercise as it works to recover your resting level of metabolic function (called homeostatis).  Your body needs time to recover and cool down, the same way a car does after it's been driven.  

While it's recovering it's going to burn calories as it works to replenish oxygen stores, remove lactic acid, repair your muscles, replenish ATP, and restore your body temperature.  HIIT also stimulates production of Human Growth Hormone (HGH).

How long does EPOC last?

Studies of the EPOC effect show vary in their results, with some claiming the effect can be noticed up to 72 hours after a HIIT session.  However, most studies note that the effect peaks within an hour of completing the exercise session, and tapers off within 16-24 hours.

The rate it tapers off, and the amount of calories burned during this period, are primarily effected by the intensity of the exercise.  The more intense the session, the higher the amount of calories burned, which isn't that surprising.  However, it also appears the the length of the exercise is not a major factor in the length of the EPOC effect.  

How to Maximize the EPOC Effect

As long as the HIIT session is at least 15 minutes, and at a high intensity, the effect is measurable and higher than when compared to a steady-state cardio session.  One study found that sprint intervals doubled the number of calories burned after exercise due to EPOC when compared to a normal jogging session.  Another found that a higher intensity workout produced the greatest afterburn effect.

Why Sprinting Burns More Fat Than Jogging

Ask people why they started jogging and most will say to lose weight, or perhaps just to "to get in shape."  To that end joggers spend hours and hours every week slogging at a steady pace, burning up miles and, hopefully, fat.

Do these people look happy to you? Photo by samchills.

But long distance runners, or those who just jog a lot, also end up burning lean muscle mass.  They lose fat, sure, but no one would point to a long distance runner and say, "There's a person in great shape."  They usually just look...drained.

When you jog, you're doing an aerobic exercise.  That means you're using glucose (from carbohydrates) and oxygen to generate energy.  The glucose in your muscles gets used up first, followed by the glycogen your body has stored up.  An adult can store around 1,800 to 2,00 calories worth of glycogen, enough to fuel 90 to 120 minutes of sustained exercise.  After that, you "hit the wall" - and that's the point at which your body finally starts converting fat into energy.

And now you know what the liver is for.

When you sprint, your body doesn't rely on oxygen to generate energy - the rapid switch from resting  to sprinting doesn't give it time.  In this type of anaerobic exercise, you'll rapidly deplete the ATP (adenosine triphosphate) in your muscles, which is enough to give you energy for 10 - 30 seconds.  When you stop sprinting, your metabolism increases as the body tries to draw in enough oxygen to begin recover its resting state. 

This post-exercise oxygen recovery (EPOC) phase can last for between 24 - 48 hours after your sprint - and it's the reason why sprinting is better for burning fat than jogging is.  Your body is working to repair the damage it incurred sprinting and to recover the depleted glucose and ATP you used up. And because sprinting is an anaerobic activity, you'll also build muscle in your recovery period.

In one study, participants were assigned to either a steady-state cardio group or a high intensity interval training (HIIT) group.  The results showed that the HIIT group burned three times more body fat than the steady-state group.  Another study found that sprint intervals decreased body fat in women by 8%.

To get the benefits of sprint interval training, you need to run, not jog.  Keep your pace to around 90% of whatever you feel your max is, and if you're not sure what you're max is, then test yourself once and see where you limits are.

It's a dramatic difference - you have to force your body to adapt to the rapid change of sprinting, and jogging isn't going to cut it.  Your sprint time should be around 30 seconds or less, depending on your fitness level, and your recovery time between sprints can vary from full minute to just 30 seconds.  Keep that up for around 15 minutes, and you'll have finished a workout that you'll feel for the rest of the day.

If you don't know how to get started with sprint interval training, you should check out Sprinterval.  It's a six-week sprint interval training program that starts easy but ramps up the intensity over the course of the program.  Before you try Sprinterval you should be able to jog continuously for at least 30 minutes (meaning you can complete a 5k without stopping), and of course, you should always consult a doctor before you start any exercise regiment.

The Benefits of Sprint Interval Training

What if you could bring your body to peak performance in less than 20 minutes at a time? Better still, what if you only had to work out 3 times a week? Get ready for a special treat; there is a way you can make it happen.

Thanks to High-Intensity Interval Training (HIIT), you can get fit faster than you would with regular exercise. You can use this method to burn fat and increase strength at a rapid rate. In fact, you could see tangible results in a couple of weeks. If you stick with HIIT for at least 6 weeks, you will get your body into the best shape of your life.

To get started, it's great to run short sprints. Why? Because that's the fastest way to make your body stronger than ever. Think about it; sprinters are some of the most powerful athletes we have today. Plus, the benefits of HIIT will spill over into other areas of your life. Here is a deeper look at why you should do sprint interval training.

Increase your stamina and fitness levels 

Doing HIIT the right way requires you to push your body to its limits. Your heart rate will shoot up very close to its maximum level. During your recovery periods, the body will try to compensate for the effort you have exerted. It will then build itself up so you can handle harder levels of physical exercise.

You will also increase your body's capacity to use high amounts of oxygen. You will then be able to do higher levels of exercise without increasing your heart rate. Of course, this means that you can push yourself even harder - and see the next level of results!

Another important aspect of sprint interval training is building lean muscle mass. Your legs are made of the biggest muscles in your body. During your training, there will be some tear in the muscle tissue - that's normal. The body will then become stronger as the muscle tissue gets repaired. Part of the fuel used in the repair comes from the fats stored in your body. Which brings you to the next crucial benefit of HIIT.

Burn fat at a rapid rate 

One of the biggest benefits of HIIT is that it helps you burn fat at a rapid rate. For the first few minutes of the workout, your body will tend to rely on your glucose supplies. But, as you keep going, your body turns into a fat-burning furnace. The high-intensity workout will melt away that fat faster than you can say "HIIT!"

After you're done, the body doesn't stop getting rid of the fat. It will keep using it as fuel whilst repairing your body. Over time, this will reduce your fat levels to a much healthier amount.

You will reduce the risk of cardiovascular disease as well. Many studies have shown that HIIT reduces the risk of heart-related death. So, you can expect to live a longer, happier life. 

Develop your mental strength 

Mental strength is a crucial part of being a high-achiever. Without it, you'll find it hard to conquer challenging goals. You will also struggle when it comes to making positive changes in your life.

But, mental strength can be developed. The focus required during your HIIT sessions will force you to build up your mental stamina. The battle you fight with your mind will equip you with skills to win in other aspects of your life.

Right from your first session, you will feel a boost in confidence and perseverance. It takes some self-control to maintain the heart rate at 85 - 95% of its maximum. If you are able to do this, you will have a superior level of self-discipline. 

With the right approach, you can steadily increase the range of challenges you can bear. Your brain will naturally adjust as you push yourself through each sprint. The best part is, your refreshed focus will stay with you after you're done with the workout. You will get more done while feeling less emotional stress.

What is the best way to get started with HIIT? 

Sprinting is great because you don't need any equipment. It's just you and your running shoes. It's easiest to get going when you have a guide you can follow.  That's where the Sprinterval app does the heavy lifting for you. What you get is an easy-to-follow workout that increases in intensity. If you're a beginner, it's a perfect way to start building up your fitness.

The app will work with you over the course of six weeks. The workouts themselves last less than 20 minutes. The key here is that you'll get the same results ( or better! ) as if you had spent hours jogging.

If you want to take your fitness to the next level, sprint interval training is your answer. The workouts are so short, you can fit it into your weekly schedule with ease. Start using the Sprinterval app today. You will get stronger so fast, you'll wish you discovered it sooner!

On Sprinting as an Adult

When was the last time you really ran? I mean ran like you were being chased.  Outside of sports adults don't really run anymore.  Sure, we jog, some of us for miles and miles and hours and hours - but there's a big difference between running and jogging.

If you decide to really run, be prepared for some weird looks.  People may get offended, like you're disturbing the natural order of things.  Sure, jogging is ok...but running? As an adult? Running is for kids!

And running at a sprint is hard.  Go try it. Run, as fast as you can, for 30 seconds.  Run like a dinosaur is chasing you.  If you haven't done it in awhile, you'll be surprised at how hard it is.  Within 20 seconds you'll be gasping for breath, ready to stop, and reconsidering your life choices.  It sure wasn't this hard to run when you were a kid, was it?

Running is a skill most of us lose at some point.  Probably shortly after we stop having recess at school.  If you're not playing a sport in high school or college, you probably never run.  Maybe, at some point you take up jogging to get back in shape, but it's not the same.

But sprinting is also fun.  When you run, when you've built up the ability to do it for more than a few seconds, you'll feel it in your bones - this is what you were meant to do.

There's a lot of medical reasons to take up high intensity interval training with sprints, but not a lot of places describing how to get back into it.  Some will advise running for 30 seconds then resting for 4 minutes, or running for a full minute and then resting for two, jogging for 15 seconds and then resting for a minute. Depending on your current activity level, maybe one of those levels is right for you, but it can be impossible to know until you go out and do it.

Sprinterval is meant to get you into sprint interval training and increase your work capacity (the amount of time you can run vs the amount of time you need to rest) over time.  Day 1 starts at running for 15 seconds, then resting for a full minute (a 1:4 work capacity).  By the end of week 6 you'll be running for 30 seconds and resting (a 1:1 work capacity). Each session takes around 15 minutes, but you'll feel the result all day long.

If you've ever done a Couch-to-5k program, you can think of Sprinterval as being the next step.  Complete the Sprinterval program and you'll see a huge decrease in your 5k time.  Of course, you may decide that jogging for 30 minutes isn't your goal anymore, because you've already found something better.