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What is Fastercise?

Fastercise is a new approach to fitness that involves short bursts of instinctive exercise (usually less than a minute) that push off hunger and greatly amplify the the signal for the body to feed off it’s own energy stores of fat and glycogen. By Fastercising when hungry you can get dramatic results with about 5 minutes a day of exercise. Dr. Denis’ book, The Power of Fastercise, explains the science behind this revolutionary fitness program. There is no faster or easier way for anyone to get fit, regardless of age, gender, physical fitness level, physical limitations, etc.

Is it really possible to only exercise for 5 minutes a day and get real results?

Yes! The Fastercise exercises (Tightercise and Shivercise) signal your body to burn the fat stored in your body for fuel while preserving and building muscle. Fastercise is so effective because it taps into your body’s instinctive survival strategies. When you understand Fastercise, you will be able to see how many programs send your body mixed messages and don’t line up with your body’s survival strategies, and it will make sense why they may not have worked for you.

What is "Shivercise" or shivering?

Shivercise is a type of exercise that mimics shivering, which you do automatically and instinctively when you get cold. You shiver because shivering uses up energy and generates heat faster than any other form of exercise. But, you don’t need to be cold to get the same benefits from shivering. Shivercise is voluntary shivering that sends such a powerful signal to your body to feed off your stored fat and glycogen that your hunger will vanish in seconds and may not come back for 30 minutes to 2 hours. When you eat a meal, you release so much energy from your food that you may not be hungry again for hours. When you Shivercise, you release so much energy from your energy stores that you may not be hungry again for hours. With Shivercise (and Tightercise), you are literally directing your body to “snack on your storage.” This allows you to get lean and toned quickly and effectively without going hungry. You Shivercise by shaking your muscles very rapidly, no more than about an inch in either direction, for up to about 1 minute. There are many positions you can use to do Shivercise, but the important thing is that you get so winded that you have to catch a full deep breath when you’re done. That shows that you’ve overwhelmed your mitochondria, which sends a strong signal to your body to increase the size and number of your mitochondria.

What is "Tightercise" or tightening?

Tightercise is a type of exercise that mimics the instinctive stretching you do every morning when you wake up. Stretching in the morning is a tool your body uses to mobilize stored energy to help get your day off to a great start. Feels great too! It also helps build muscles that need strengthening, which explains why you sometimes contort your body into strange positions to get the right stretch. You can use Tightercise to direct your body to strengthen and grow certain muscles. Tightercise involves first shortening or balling up a muscle (i.e. for your bicep, you bend your arm till your hand reaches your shoulder) and then clenching that muscle as hard as you can for a period of 2-5 seconds, or until the muscle starts to hurt a little or feels like it’s starting to cramp. You can do this with any muscle or muscle group that you want to build, usually a few minutes before or after eating. This communicates to the body that you need these muscles in order to survive, so the body will prioritize building them quickly and efficiently.

What are mitochondria?

Your body uses food as fuel to generate the energy that powers your body. Ninety-five percent of that energy is produced inside your cells by structures called mitochondria. The more mitochondria you have, the faster and more easily you can generate energy to power everything your body does. Including burning fat, building muscle, fighting infection, recovering from injury, thinking, talking, dancing, working, refurbishing the body during sleep…well, you get the picture.

Why does Fastercise focus on building up mitochondria?

Fastercise focuses on building up the size and number of your mitochondria through both Shivercise and Tightercise to help shift your body away from “storage mode” and toward “forage mode,” away from using food to build up your fat stores and toward using up your fat stores to obtain food. This laser-focused approach is designed to not only help you get quick resultts (in 1 or 2 weeks of trying the program) but also to help shift your body’s tendencies so you may experience fitness like you’ve never achieved before that you can easily maintain.

What diet should I maintain?

It depends on what your coach recommends. We have two diet options with Fastercise: a keto diet and a carb-friendly diet. A keto diet can help emphasize burning fat, whereas a carb-friendly diet can help emphasize building muscle. The choice between the two will depend on your priorities.

How quickly will I see results?

Many people see results within the first week, and certainly within the first month. This program has helped people with all kinds of goals, from getting more toned muscles to losing more than 75 pounds (in some cases, in just a matter of months). Your results can vary depending on how aggressively you implement the program.

What if I can’t do the program throughout the day? Is there a way I can make it work for me?

Yes, Fastercise is the most flexible fitness program we know of and can be arranged to fit into almost any lifestyle. You can work with your coach to create a program that apply the Laws of Fastercise around your work and other activities. The best fitness program for you is one that you can happily maintain.

What does the cadence of Fastercise look like throughout the day?

When you wake up, Tightercise and/or Shivercise to for a minute or two to get a great start on your day. When you get hungry, Shivercise and/or Tightercise to push off your hunger for a time. When you get hungry again, you can Shivercise and/or Tightercise again to push off hunger again. You can repeat this process a number of times if you wish. If you find your hunger is becoming too distracting because it’s not staying gone for more than 15 minutes or so, you can Shivercise or fastercise one more time and then eat within about 10 minutes. After you’ve eaten, you can do a Tightercise routine. One very simple approach would be to go through the following cycle two or three times a day, depending on how many meals you eat: [get hungry, Shivercise, get hungry, Shivercise then eat, Tightercise when finished eating]. And that’s it!

What do I do if I’ve hit a plateau and can’t seem to lose more weight?

Your body’s key priority is to survive. And your body can tell when you’ve lost weight. It might think that you’re starving, and you need to hold onto fat reserves. In response, it will adjust your hormones to prevent more weight loss for a time. This will usually last about one week. To move past this plateau, continue doing the program and try to relax. Cortisol is a hormone your body releases when you are stressed, which can also halt weight loss. Try to relax, do the program, and let your body work. After a few days, your body will realize it doesn’t need to hold the weight, and you’ll likely experience a gradual or dramatic drop in weight.

What can I eat and what can I not eat?

Depending on your goals (fat burning or muscle building), you’ll either maintain a keto diet or a carb-friendly diet. In either case, you’ll avoid refined starches and sugars, such as breads, pastas, pizza, tortillas, chips, crackers, cookies, cakes, ice cream, soda, etc. If you’re on the keto diet, you’ll also only eat 50 grams of carbs a day or less, so avoiding potatoes, quinoa, brown rice, etc. The meal plans we provide will give you ideas of what to eat throughout the week. Your coach can also provide direction.

Should I combine intermittent fasting with Fastercise?

While you can still apply the principles and laws of Fastercise without following an intermittent fasting regimen, you’ll find that you may automatically end up with such an eating pattern with Fastercise anyway.

The idea of intermittent fasting is to spend less time each day in the fed state which is just what Fastercise helps you to accomplish. One approach to intermittent fasting is to eat fewer meals a day, and other approach is to restrict your eating to a certain window of time each day.

For example, you might eat only twice instead of 3-5 times a day, or you might eat only between the hours of 12p and 8p each day. With Fastercise, you eat after you’ve pushed off hunger once or twice. For many, this means that their first meal is around lunch time anyway. And then they may not need to eat again until dinner.

The hormonal effects of intermittent fasting and Fastercise are so similar that you can think of Fastercise as amplifying the effects of intermittent fasting. In fact, without Fastercise you may find yourself going hungry at times when you are doing intermittent fasting. We recommend that you push off your hunger with Fastercise instead of going hungry because hunger is a sign that you’re burning muscle. When you let your hunger go away on its own, you may be signaling your metabolism to slow down a little.

Another potential difference between intermittent fasting (IF) and Fastercise is that with IF, you eat at any time during your feeding period; with Fastercise, we suggest you push off hunger with Fastercise at least once between meals. Combining exercises with the timing of your meals maximizes the benefits of the fed as well as benefits of the non-fed state.

Should I eat food even if I'm not hungry? My appetite has gone down since I started the program.

If you’re maintaining your Fastercise program and you find that you’re not hungry for long stretches of time, this is a sign that the program is working for you! You are successfully tapping into your body’s stored fuel, and thus need to eat less. In these periods of time, be sure to drink plenty of water and take your electrolytes to make sure you avoid cramps.

Sometimes I'm out and about and get very hungry with no food. What should I do?

Shivercising, taking a MAP pill and drinking plenty of water in situations like these is a great option. Be sure to have this protein supplement in your bag or car or other place you can easily access it. In this way, you are able to tap into your stored body fat reserves, and you also provide your body with readily-absorbable protein which can help you preserve and build your muscle. If you want, you can also have cheese sticks, almonds, peanuts, jerky, and other similar snacks in the place of MAP pills.

How do I know when to stop eating during a meal?

This will take some practice, so don’t worry about nailing it the first time. If you eat slowly, your body will be able to tell you when it doesn’t need more food. Did you know that because of the time it takes for your food’s nutrients to be absorbed into your bloodstream, you’ll know you ate enough 5 minutes after it happens? So, it’s important to eat slowly enough to see how you’re feeling so you catch your body’s signal that you’re no longer hungry. Your coach can also help you fine-tune your eating experience. If you get hungry again within an hour of eating, you might want to eat slightly larger meals.

What is a carb-friendly diet and should I do it? 

A carb-friendly diet is basically a well-rounded, whole-food focused diet. A carb-friendly diet can be helpful if you want to focus on building muscle. Our guidelines for this are 1. Eat only complex carbs (sweet potatoes, quinoa, brown rice, etc.), 2. Each plate/meal should be about half vegetables, a quarter protein, and a quarter complex carbs, and 3. When you eat, just eat until you’re no longer hungry (no more, no less).

What is keto and should I do it? 

Keto is a low-carb diet that focuses on getting your primary fuel from fat and protein instead of carbohydrates. A keto diet can be helpful if you want to focus on burning your fat stores, and would like to see results sooner rather than later. With Fastercise, we only have a few guidelines to maintain a keto diet: 1. Eat 50 total grams of carbs or less a day, 2. Take your electrolytes every day, and 3. When you eat, just eat until you’re no longer hungry. We have 12 weeks of meal plans that you can use to maintain this diet, and your coach can also help guide you in how to handle your meal plan.

Will my metabolism slow down if I'm not eating as much as I used to?

Not at all. In fact, Shivercise and Tightercise can speed up your metabolism. So rather than eating in the morning to get your metabolism started, you can Fastercise to boost your metabolism. You won’t feel as hungry throughout the day, and that’s a sign that you’re using your stored fuel (fat) as your energy source. If you find that you go long stretches of time throughout the day without feeling hungry, and you’re maintaining your Fastercise program, this is a sign that your body is maintaining itself with its stored fuel. You will likely see weight loss in the days to follow as well.

Can I still do sports that I enjoy with Fastercise?

You can still do pretty much anything you already enjoy in addition to Fastercise. Just be aware that thirty to forty-five minutes of demanding physical activity such as cycling, jogging, intense gym exercise, etc.) deplete your body’s energy stores (particularly glycogen) which can make it difficult or impossible to push off hunger for very long with Fastercise and to flex your muscles as hard as possible. Activities you can do while still having a conversation do not deplete your energy stores as much.

Ironically, thirty to forty-five minutes of strenuous exercise may also send your body the signal to conserve its energy stores. This explains why some people that run on a treadmill for 45 minutes three times a week can actually gain weight. Shockingly, you may find that you burn more fat and build more muscle by simply Fastercising 5 minutes a day!

How should I breathe while I’m Tightercising and Shivercising?

Try to breathe in a controlled manner during both exercises. You don’t want to hold your breath, but you also don’t want to breathe very rapidly and get dizzy. If you’d like to practice, breathe deeply in for two seconds, then breathe out for two seconds, in for two, out for two. That’s a good tempo.

How often do I Shivercise and Tightercise throughout the day?

Two or three rounds of Shivercise, eat, Tightercise in any given day is enough to give you excellent results. By pushing off your hunger with Shivercise, then eating until you’re no longer hungry, you will find that you only need to eat 3 times a day, and maybe only twice. This isn’t because you’re depriving yourself, but because you simply don’t need to eat as much as before. Since you’re tapping into stored body-fat, you’re still “well-fed” without needing to eat as much. You can simply make sure to Shivercise before you eat and Tightercise after.

Of course, you can Fastercise at other times as well. For example, if you ever feel chilly you can Fastercise to warm up. You can Fastercise when you’re feeling drowsy and want to wake up and increase your mental focus and productivity for a time. You can also Fastercise to let off some stress or to have fun, celebrate life, and lift your spirits.

How many times should I push off hunger with exercise before I eat?

You can choose how many times to push off hunger before you eat, but we recommend no more than 3 times. When you repeatedly push off hunger with Fastercise, each time your hunger tends to return sooner. While your hunger might have stayed away for 2 hours after the first bout, it might only stay away for 45 minutes the second, and maybe only 10 minutes the third. This is because your body has less readily-available energy stores each time because it is using them up. Once you’re ready to eat, fastercise one more time and then relax and eat until you’re no longer hungry.

How long will exercise push off hunger?

When you get hungry, we typically recommend pushing off your hunger with enough Shivercise to catch a full, deep breath (usually a minute or less). If you’re in a place where it would be too socially awkward to do Shivercise, you can do a hard Tightercise clench, tightening as many of your muscles as you can at the same time.. Either should push off your hunger anywhere from 30 minutes to 2 hours.

How do I know I’m doing Tightercise right?

If your muscle gives out after clenching very hard for 2-5 seconds, you’re doing Tightercise right. If not, you’re not clenching hard enough. Everyone, regardless of fitness level, can reach this “burnout” in 2-5 seconds. The important thing is to go for intensity over sustainability: you want to clench your muscles as hard as you possibly can. It’s difficult to achieve this with usual gym exercises because it’s easy for the resistance to be either too low or too high to fully shorten and clench your muscle. But since you’re just using your own fresh muscles in Tightercise, you face practically no risk of injury. So, you might be able to safely engage your muscles harder and get better results than you ever have before.

How do I know I’m doing Shivercise right?

When you move your muscles, they generate acid. The faster you move them the faster they generate acid. When the acid levels get too high in your muscles they start to slow down or even stop moving. To be able to keep moving your muscles, your breathing speeds up to lower acid levels in your muscles. The faster you shiver the faster the acid builds up and the faster you breathe. If you shiver fast enough, you will feel so “winded” or “out-of-breath” that you’ll feel like you have to start slowing down and you’ll be able to catch a full, deep breath. This full, deep breath is your sign that you have overcome your mitochondria so thoroughly that you’ve have signaled your body to make more mitochondria so your body can be better prepared the next time you decide to shiver.

No, you don’t have to be cold to shiver. You can voluntarily shiver even when you’re not cold. You might wonder if you can get the same benefit from having your body vibrated by a machine. If you don’t get winded enough to catch a deep breath you are not achieving the same effect. Most adults rarely (if ever) exercise so fast that they get so winded that they catch a deep breath and have to stop. For one thing, many people might hurt themselves if they tried to run that fast, but by moving your body as fast as you possibly can for about 1 minute, you can safely involve many muscles at once and you might easily get results that you’ve never seen before. You may find that you can run faster and longer and sprint harder than you have before, even though you’re not running regularly.

How do I submit an exercise I’ve created myself?

E-mail us at with a video of you doing the exercise. Also, please include your name, a quick story about your experience with Fastercise, and what you’d like the new exercise to be called. We reserve the right to rename the exercise, however (we can't put anything obscene on our website). 

Can I do Fastercise if I have a chronic illness? 

Yes, in fact, people with chronic illness tend to exercise less for one reason or another which may actually contribute to their illness. Fastercise may be the very thing many people with chronic illnesses need to feel better since it works in harmony with the body’s survival mechanisms. Although Fastercise is safe for practically everyone to do, we recommend you consult with your doctor.

Can I do Fastercise while recovering from surgery, childbirth, etc? 

Yes, but we do recommend getting your doctor’s approval. Since the Fastercise exercises are effective even from a sitting/lying down position and only involve tightening or shivering some of your muscles, it poses very little risk to your recovery. In many cases, it can actually help aid in recovery, since it increases lactate and growth hormone which both promote wound healing. In addition, it can help maintain and increase the size and number of mitochondria which provide the energy to fight infection and repair tissue. While you may not be able to do every type of exercise offered by the program, there are many exercises you probably will be able to do. Please see our video library for exercises you can do while recovering or if you have a physical disability.

Is it safe to breastfeed and do Fastercise?

Yes, you can breastfeed and do Fastercise. You may need to experiment with how your body responds to timing your meals based on hunger, but your milk supply should remain constant throughout. After all, Fastercise is patterned after the lifestyle of our hunter-gatherer ancestors.

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