Dr. Jordan Metzl's Workout Prescription

10, 20 & 30-minute high-intensity interval training workouts for every fitness level

Dr. Jordan Metzl's Workout Prescription is a compressed workout guide designed for busy professionals in today's world who have little time for fitness and want to maximize results. In this book, Dr. Jordan Metzl explains the science of the compressed, high-intensity workout and provides a series of progressive workouts ranging from 10 to 30 minutes that can be done anytime, anywhere, using minimal equipment.

This book also guides you through topics like motivation, goals, and the importance of proper recovery. Dr. Metzl's high-intensity workout, combined with a scientifically designed and periodized training schedule, delivers maximum results in minimum time in a unique and compelling way that is equally effective for men and women, children and adults.
CHAPTER ONE

STEP 1: IT'S NOT ABOUT TIME
(Though 30 Minutes Is a Sweet Spot!)

Time is a funny thing. It flies. It drags. And yet time is the same every time. Sixty seconds in every minute, 60 minutes in every hour, and so on. That means that after 30 minutes, you've burned 1,800 seconds, whether you were standing in line to get a driver's license photo or watching your favorite TV comedy. The only difference is how each of those 1,800 seconds felt as it ticked away.

In other words, how you fill the time ultimately determines what you get out of it.

If you happen to be on the phone with a friend you haven't spoken with in a year, you won't even realize there's a wait for that driver's license photo. Meanwhile, if that episode of your favorite show is a rerun, your mind may wander and time will pass more slowly.

Time is like that for just about every activity, but nothing gives people more fits than time partnered with exercise. Consider:

• What's the most common thing you hear about exercise? "I don't have time."

• Packing a bag, driving to the gym, changing, working out, cooling down, showering (hopefully!), changing again, and returning to your day-- all represent little pockets of time. They add up.

• What about those seconds ticking away during a workout? Well, let's just say that some seconds tick faster than others. (I can vouch for that: Mile 2 of a marathon ticks away a lot faster than, say, Mile 22.)

• And then there's the biggest issue of all, the problem this book was designed to solve: How much time do you really need to exercise effectively?

The answer? Well, I'm not sure a definitive answer exists. The science is pretty clear in that the health benefits level off at around 150 minutes per week of moderate activity, which equates to 30 minutes of brisk walking 5 days a week. That's a solid recommendation, and it makes 30 minutes one kind of sweet spot. But is it definitive? Nope. Someone who wants to run a marathon needs more exercise than someone who just wants to enjoy a Spinning class with friends. Still, if you want to feel better, improve your health, build strength, and live a more active lifestyle, you need very little time to exercise. In fact, it comes down to the title of this chapter: To get real benefits from exercise, it's not about time. It's about what you put into the time you have--the types of exercises and the intensity with which you perform them. Once you master that concept, the clock becomes a very good friend indeed.

Know Before You Go (This Is Important!)

I recommend that anyone who wants to ramp up his or her exercise activity see a doctor for a full physical beforehand. This is especially true for anyone who has been inactive for a while or is over age 40 (or both). Let the doc know what you have planned and that you want to know that the machine is in good working order before you start. This isn't a disclaimer-- this is smart medical advice for several reasons.

• Your doctor can give you a thorough going-over, including examining your medical history. This is especially crucial if you've had past physical issues like chest pain, dizziness, or even joint pain.

• Your doctor can help guide your fitness plan. She's probably not a trainer, but she can give you advice on how hard you should go based on your physical condition. And listen to her. One thing about gung-ho humans: Their eyes are bigger than their stomachs (and muscles and cardiovascular fitness level).

• You'll establish baseline numbers for your blood pressure, cholesterol, and all those other wonderful markers you should have memorized but probably don't. Improving your fitness generally improves your health stats. Don't you want to know how well you're doing? That's part of the payoff!

INTENSITY, EFFICIENCY, TOTALITY

This book promises 30-minute workouts--and you'll find a bunch of them in here--but the fact is, you can do the 10- and 20-minute versions and still enjoy health benefits, build muscle, and increase your overall fitness. How? Again, it's about intensity and volume--how hard you work and how much work you do in a given time period.

I'm a big endurance sports guy. I run marathons and do Ironman triathlons. Those are timed events, which means that the better I perform in a race, the shorter that race is for me. (Now there's some incentive to swim, run, and pedal faster--it'll all be over sooner.) But if you have a set time for a workout, it's kind of like an empty box on moving day. You could toss a bunch of stuff into it and put it on the truck, but then you'd probably need more empty boxes to get the end result you want, which is all your stuff on the truck.

But what if you learned how to pack the box more efficiently? To use all the space in the box? And do it in half the time? You'd get all your stuff on the truck in one shot and boom, you'd be done.

That's what this book will help you do. How? By focusing on intensity, efficiency, and totality.

• Intensity. The workouts in this book (whether 10 minutes, 20 minutes, or 30 minutes) consist of high-intensity interval training, or HIIT. You may have heard of HIIT. We'll discuss it in more detail shortly, but the bottom line is that HIIT workouts deliver incredible performance results--you'll be better, stronger, and faster, for sure--but also serious, research-backed health benefits. The ever-expanding science of HIIT shows that you can achieve better physical, mental, and physiological results if you're able to master this type of workout. (I think it's worth it!)

• Efficiency. Most of the exercises in the 30-minute workouts are designed to work multiple muscles across a series of com£d movements. A single-movement exercise like a biceps curl is just fine for your biceps, but not very efficient for the rest of your body. If you can engage dozens of muscles in 5 seconds versus just a few muscles, which strategy gets more done? Using the moving box analogy, these exercises pack more activity and muscle engagement into a smaller space (or time, as it were).

• Totality. I'm all about total-body fitness. Yes, I offer some targeted workouts for your core, lower body, and upper body later in the book, but the overall mission is building your entire body in a balanced way to help it perform better and prevent injury. Oh, and your day-to-day life will be easier--from climbing stairs to hauling laundry. Total-body fitness leads to total-life payoffs.

Why I Believe Exercising 7 Days a Week Is an Awesome Idea

Exercising 7 days a week sounds extreme, but it really isn't. Some people out there would immediately say, "No way--your body needs time to recover. Why would a doctor recommend something so crazy?"

It's pretty simple: I believe the human body is designed for everyday use. We're mobile creatures. Sofas are a relatively new invention. Just look back a hundred years, five hundred, a thousand, and more. Our ancestors, from the caves to the farm fields, got their butts out the door early and sweated all day, every day. The difference is they did it because they had to, without any real knowledge of how to take care of themselves and with very little medical care. Well, we can do it because we want to, it's good for us, and we know so much more today (and if you do injure yourself, you probably won't die like in the old days).

The key to daily exercise? Avoiding overuse. How do you do this?

Change it up. Do something different from your normal workouts, and go easier than you normally do. Bring friends. Smile a lot. I call this kind of movement dynamic rest and talk about it in more detail later in the book- -with suggestions!

I look at daily exercise as a healthy addiction. We have such an obesity problem and so many obesity-related health issues that are treated after they happen, as opposed to trying to prevent them in the first place. Hypertension and diabetes are preventable and potentially reversible with daily exercise. Exercise is medicine, preventive medicine, and I believe it should be a daily ritual just like brushing your teeth.

My point is, a body that is used sensibly every day grows accustomed to being used and won't be as prone to injury.

SCORE YOUR FIRST BIG HIIT (OR, HOW MANY PLAYS ON THE TERM HIIT CAN WE FIT INTO ONE BOOK?)

Interval training isn't new. Runners have a classic German term for it-- fartlek--which has inspired jokes among high school cross-country teammates for decades. People who use intervals in any kind of training know how well they work.

So what is HIIT? It's simple: Instead of exercising at one pace for an extended period of time--think jogging 3 miles on a Saturday morning--you work at a higher intensity for short intervals of time (thus the name) with rest periods figured in. So a runner, for example, would run at a much faster pace for, say, 30 seconds, then dial it back for a minute, and then ramp back up for 30 seconds more, etc. That's a very basic example; there are limitless ways you can break up intervals and rest periods, and you can apply the concept to any activity (even bowling, though that would be . . . strange).

Steady-state cardio exercises like running are good for you--fantastic, even--and do challenge your body. However, over long periods, they ultimately train your physique to be more efficient. Think how elite distance runners have more compact frames--their bodies have been trained to use energy more efficiently; therefore, their muscles have adapted to be smaller to consume fewer resources for the effort exerted.

Now consider the sprinter: bigger muscles, more explosive fast-twitch fibers, built not for long-haul efficiency but for short-burst intensity. Sprinters by default use interval training because they need that all-out, leave-nothing-in-the-tank effort to get to the finish line first.

That's HIIT in a nutshell. But what does it do for you? And how does it do it?

Working at the high-intensity level raises your heart rate and increases your body's oxygen consumption. This can lead to burning more calories and fat. In fact, your body continues consuming oxygen after the workout is over, sometimes for hours. This is known as excess post-exercise oxygen consumption, or EPOC. I use this concept all the time in my office. I talk to my patients about turning on their "metabolic furnace" for the day by using intensity first thing in the morning. Exactly how many more calories are burned? It's difficult to calculate--every person's body is different-- but it can be as high as 25 to 30 percent more, compared with steady-state workouts, according to the American College of Sports Medicine.

So: shorter workouts, higher oxygen and calorie burn, better total-body fitness. Not a bad collection of benefits. But like a bad infomercial-- wait! There's more!

HIIT has been around long enough that researchers have had time to study its various effects on the body, and I expect more research to pile up as the years go by, since HIIT is a rich subject. Aside from considering all the information I've just given you, have a look at some of the scientifically tested benefits of adding HIIT strength sessions to your regular exercise regimen (or, if you're fresh off the couch and just starting, why HIIT should be part of whatever you're planning to try, be it a simple walking program or something more ambitious). I think you'll be happy you did.

HIIT--specifically, with strength training--helps deliver a bigger burn.

I touched on this just now, but we haven't talked about the benefits of strength training (as opposed to steady-state cardio like running or cycling). A small study in the journal Medicine and Science in Sports and Exercise1 monitored the oxygen consumption (known as VO2 max, a measurement based on body weight and lung capacity) of 15 men as they performed interval-style weight training for 27 minutes, and then, 5 days later, ran steady-state on treadmills to achieve identical VO2 levels for 27 minutes. In other words, they did weight training and treadmill running at the same effort level for the same amount of time. The result? Total oxygen consumption was higher for 30 minutes after the weight-training workout.

Another study--this time of seven women ages 22 to 35, in the International Journal of Sport Nutrition and Exercise Metabolism,2--showed elevated metabolic rate for 3 hours after an intense resistance workout, compared with pre-exercise levels. To boot, resting fat oxidation was elevated 2 days after the workout.

That's exciting stuff. HIIT has long been thought to help boost metabolism and "afterburn." Still, some data have shown that the fitter you are, the lower your EPOC. A study of 10 men in the journal BMC Research Notes in 20123 showed just that--though this study looked at cardio, not strength training.

These are small studies and just examples of what kind of research has been going on in the world of HIIT, but they give a glimpse of the overall potential benefits. In conclusion, the harder you work, the more physiologically efficient you'll become, achieving better results in less time.

What about Cardio?

I compare HIIT to steady-state cardio a lot in this chapter. That doesn't mean I'm anti-cardio. I run, bike, and swim more than most folks as I train for Ironman triathlons. I love those activities and wouldn't give them up for anything. They bring unbelievable mental and physical rewards. But as much as I want to do them, I want to have total-body fitness. I want the strength and flexibility that HIIT gives me. And my HIIT workouts have improved my steady-state performance. There's no downside.

But here's another reason I love HIIT for strength: You work your muscles, but you also work at an intensity high enough to give you a first-rate cardio challenge while simultaneously building strength. My patients often ask, "Is this a strength day or a cardio day?" The truth is that when you do HIIT, it's just a day. You're building both strength and cardiopulmonary fitness at the same time. You can do nothing but these workouts a few times a week and get yourself stronger and in great cardiovascular shape. Now that's a comprehensive workout.

Can a 10-Minute Workout Really Deliver Health and Fitness Benefits?

Yes, it can. Research has begun to consistently bear this out: A recent study in the journal PLOS ONE4 had otherwise-healthy obese participants perform 3 minutes of intense intermittent exercise within a 30-minute weekly training time commitment for 6 weeks (three sessions of 10 minutes that included 1 minute of intervals per week). The results: improved oxygen consumption, lower blood pressure, and increased insulin sensitivity. And that was just from adding 1 minute of intense exercise in a 10-minute training window three times a week.
Jordan Metzl, MD, is the author of The Exercise CureThe Athlete's Book of Home Remedies, andDr. Jordan Metzl's Running Strong. He is a nationally known sports medicine physician at New York City's Hospital for Special Surgery. He appears regularly on the esteemed New York Magazine's Top Doctors list. Prior to joining NYC Hospital for Special Surgery, Dr. Metzl completed his fellowship in sports medicine and dance medicine at Harvard Medical School and Boston Children's Hospital. He lives in New York City. View titles by Jordan Metzl

About

Dr. Jordan Metzl's Workout Prescription is a compressed workout guide designed for busy professionals in today's world who have little time for fitness and want to maximize results. In this book, Dr. Jordan Metzl explains the science of the compressed, high-intensity workout and provides a series of progressive workouts ranging from 10 to 30 minutes that can be done anytime, anywhere, using minimal equipment.

This book also guides you through topics like motivation, goals, and the importance of proper recovery. Dr. Metzl's high-intensity workout, combined with a scientifically designed and periodized training schedule, delivers maximum results in minimum time in a unique and compelling way that is equally effective for men and women, children and adults.

Excerpt

CHAPTER ONE

STEP 1: IT'S NOT ABOUT TIME
(Though 30 Minutes Is a Sweet Spot!)

Time is a funny thing. It flies. It drags. And yet time is the same every time. Sixty seconds in every minute, 60 minutes in every hour, and so on. That means that after 30 minutes, you've burned 1,800 seconds, whether you were standing in line to get a driver's license photo or watching your favorite TV comedy. The only difference is how each of those 1,800 seconds felt as it ticked away.

In other words, how you fill the time ultimately determines what you get out of it.

If you happen to be on the phone with a friend you haven't spoken with in a year, you won't even realize there's a wait for that driver's license photo. Meanwhile, if that episode of your favorite show is a rerun, your mind may wander and time will pass more slowly.

Time is like that for just about every activity, but nothing gives people more fits than time partnered with exercise. Consider:

• What's the most common thing you hear about exercise? "I don't have time."

• Packing a bag, driving to the gym, changing, working out, cooling down, showering (hopefully!), changing again, and returning to your day-- all represent little pockets of time. They add up.

• What about those seconds ticking away during a workout? Well, let's just say that some seconds tick faster than others. (I can vouch for that: Mile 2 of a marathon ticks away a lot faster than, say, Mile 22.)

• And then there's the biggest issue of all, the problem this book was designed to solve: How much time do you really need to exercise effectively?

The answer? Well, I'm not sure a definitive answer exists. The science is pretty clear in that the health benefits level off at around 150 minutes per week of moderate activity, which equates to 30 minutes of brisk walking 5 days a week. That's a solid recommendation, and it makes 30 minutes one kind of sweet spot. But is it definitive? Nope. Someone who wants to run a marathon needs more exercise than someone who just wants to enjoy a Spinning class with friends. Still, if you want to feel better, improve your health, build strength, and live a more active lifestyle, you need very little time to exercise. In fact, it comes down to the title of this chapter: To get real benefits from exercise, it's not about time. It's about what you put into the time you have--the types of exercises and the intensity with which you perform them. Once you master that concept, the clock becomes a very good friend indeed.

Know Before You Go (This Is Important!)

I recommend that anyone who wants to ramp up his or her exercise activity see a doctor for a full physical beforehand. This is especially true for anyone who has been inactive for a while or is over age 40 (or both). Let the doc know what you have planned and that you want to know that the machine is in good working order before you start. This isn't a disclaimer-- this is smart medical advice for several reasons.

• Your doctor can give you a thorough going-over, including examining your medical history. This is especially crucial if you've had past physical issues like chest pain, dizziness, or even joint pain.

• Your doctor can help guide your fitness plan. She's probably not a trainer, but she can give you advice on how hard you should go based on your physical condition. And listen to her. One thing about gung-ho humans: Their eyes are bigger than their stomachs (and muscles and cardiovascular fitness level).

• You'll establish baseline numbers for your blood pressure, cholesterol, and all those other wonderful markers you should have memorized but probably don't. Improving your fitness generally improves your health stats. Don't you want to know how well you're doing? That's part of the payoff!

INTENSITY, EFFICIENCY, TOTALITY

This book promises 30-minute workouts--and you'll find a bunch of them in here--but the fact is, you can do the 10- and 20-minute versions and still enjoy health benefits, build muscle, and increase your overall fitness. How? Again, it's about intensity and volume--how hard you work and how much work you do in a given time period.

I'm a big endurance sports guy. I run marathons and do Ironman triathlons. Those are timed events, which means that the better I perform in a race, the shorter that race is for me. (Now there's some incentive to swim, run, and pedal faster--it'll all be over sooner.) But if you have a set time for a workout, it's kind of like an empty box on moving day. You could toss a bunch of stuff into it and put it on the truck, but then you'd probably need more empty boxes to get the end result you want, which is all your stuff on the truck.

But what if you learned how to pack the box more efficiently? To use all the space in the box? And do it in half the time? You'd get all your stuff on the truck in one shot and boom, you'd be done.

That's what this book will help you do. How? By focusing on intensity, efficiency, and totality.

• Intensity. The workouts in this book (whether 10 minutes, 20 minutes, or 30 minutes) consist of high-intensity interval training, or HIIT. You may have heard of HIIT. We'll discuss it in more detail shortly, but the bottom line is that HIIT workouts deliver incredible performance results--you'll be better, stronger, and faster, for sure--but also serious, research-backed health benefits. The ever-expanding science of HIIT shows that you can achieve better physical, mental, and physiological results if you're able to master this type of workout. (I think it's worth it!)

• Efficiency. Most of the exercises in the 30-minute workouts are designed to work multiple muscles across a series of com£d movements. A single-movement exercise like a biceps curl is just fine for your biceps, but not very efficient for the rest of your body. If you can engage dozens of muscles in 5 seconds versus just a few muscles, which strategy gets more done? Using the moving box analogy, these exercises pack more activity and muscle engagement into a smaller space (or time, as it were).

• Totality. I'm all about total-body fitness. Yes, I offer some targeted workouts for your core, lower body, and upper body later in the book, but the overall mission is building your entire body in a balanced way to help it perform better and prevent injury. Oh, and your day-to-day life will be easier--from climbing stairs to hauling laundry. Total-body fitness leads to total-life payoffs.

Why I Believe Exercising 7 Days a Week Is an Awesome Idea

Exercising 7 days a week sounds extreme, but it really isn't. Some people out there would immediately say, "No way--your body needs time to recover. Why would a doctor recommend something so crazy?"

It's pretty simple: I believe the human body is designed for everyday use. We're mobile creatures. Sofas are a relatively new invention. Just look back a hundred years, five hundred, a thousand, and more. Our ancestors, from the caves to the farm fields, got their butts out the door early and sweated all day, every day. The difference is they did it because they had to, without any real knowledge of how to take care of themselves and with very little medical care. Well, we can do it because we want to, it's good for us, and we know so much more today (and if you do injure yourself, you probably won't die like in the old days).

The key to daily exercise? Avoiding overuse. How do you do this?

Change it up. Do something different from your normal workouts, and go easier than you normally do. Bring friends. Smile a lot. I call this kind of movement dynamic rest and talk about it in more detail later in the book- -with suggestions!

I look at daily exercise as a healthy addiction. We have such an obesity problem and so many obesity-related health issues that are treated after they happen, as opposed to trying to prevent them in the first place. Hypertension and diabetes are preventable and potentially reversible with daily exercise. Exercise is medicine, preventive medicine, and I believe it should be a daily ritual just like brushing your teeth.

My point is, a body that is used sensibly every day grows accustomed to being used and won't be as prone to injury.

SCORE YOUR FIRST BIG HIIT (OR, HOW MANY PLAYS ON THE TERM HIIT CAN WE FIT INTO ONE BOOK?)

Interval training isn't new. Runners have a classic German term for it-- fartlek--which has inspired jokes among high school cross-country teammates for decades. People who use intervals in any kind of training know how well they work.

So what is HIIT? It's simple: Instead of exercising at one pace for an extended period of time--think jogging 3 miles on a Saturday morning--you work at a higher intensity for short intervals of time (thus the name) with rest periods figured in. So a runner, for example, would run at a much faster pace for, say, 30 seconds, then dial it back for a minute, and then ramp back up for 30 seconds more, etc. That's a very basic example; there are limitless ways you can break up intervals and rest periods, and you can apply the concept to any activity (even bowling, though that would be . . . strange).

Steady-state cardio exercises like running are good for you--fantastic, even--and do challenge your body. However, over long periods, they ultimately train your physique to be more efficient. Think how elite distance runners have more compact frames--their bodies have been trained to use energy more efficiently; therefore, their muscles have adapted to be smaller to consume fewer resources for the effort exerted.

Now consider the sprinter: bigger muscles, more explosive fast-twitch fibers, built not for long-haul efficiency but for short-burst intensity. Sprinters by default use interval training because they need that all-out, leave-nothing-in-the-tank effort to get to the finish line first.

That's HIIT in a nutshell. But what does it do for you? And how does it do it?

Working at the high-intensity level raises your heart rate and increases your body's oxygen consumption. This can lead to burning more calories and fat. In fact, your body continues consuming oxygen after the workout is over, sometimes for hours. This is known as excess post-exercise oxygen consumption, or EPOC. I use this concept all the time in my office. I talk to my patients about turning on their "metabolic furnace" for the day by using intensity first thing in the morning. Exactly how many more calories are burned? It's difficult to calculate--every person's body is different-- but it can be as high as 25 to 30 percent more, compared with steady-state workouts, according to the American College of Sports Medicine.

So: shorter workouts, higher oxygen and calorie burn, better total-body fitness. Not a bad collection of benefits. But like a bad infomercial-- wait! There's more!

HIIT has been around long enough that researchers have had time to study its various effects on the body, and I expect more research to pile up as the years go by, since HIIT is a rich subject. Aside from considering all the information I've just given you, have a look at some of the scientifically tested benefits of adding HIIT strength sessions to your regular exercise regimen (or, if you're fresh off the couch and just starting, why HIIT should be part of whatever you're planning to try, be it a simple walking program or something more ambitious). I think you'll be happy you did.

HIIT--specifically, with strength training--helps deliver a bigger burn.

I touched on this just now, but we haven't talked about the benefits of strength training (as opposed to steady-state cardio like running or cycling). A small study in the journal Medicine and Science in Sports and Exercise1 monitored the oxygen consumption (known as VO2 max, a measurement based on body weight and lung capacity) of 15 men as they performed interval-style weight training for 27 minutes, and then, 5 days later, ran steady-state on treadmills to achieve identical VO2 levels for 27 minutes. In other words, they did weight training and treadmill running at the same effort level for the same amount of time. The result? Total oxygen consumption was higher for 30 minutes after the weight-training workout.

Another study--this time of seven women ages 22 to 35, in the International Journal of Sport Nutrition and Exercise Metabolism,2--showed elevated metabolic rate for 3 hours after an intense resistance workout, compared with pre-exercise levels. To boot, resting fat oxidation was elevated 2 days after the workout.

That's exciting stuff. HIIT has long been thought to help boost metabolism and "afterburn." Still, some data have shown that the fitter you are, the lower your EPOC. A study of 10 men in the journal BMC Research Notes in 20123 showed just that--though this study looked at cardio, not strength training.

These are small studies and just examples of what kind of research has been going on in the world of HIIT, but they give a glimpse of the overall potential benefits. In conclusion, the harder you work, the more physiologically efficient you'll become, achieving better results in less time.

What about Cardio?

I compare HIIT to steady-state cardio a lot in this chapter. That doesn't mean I'm anti-cardio. I run, bike, and swim more than most folks as I train for Ironman triathlons. I love those activities and wouldn't give them up for anything. They bring unbelievable mental and physical rewards. But as much as I want to do them, I want to have total-body fitness. I want the strength and flexibility that HIIT gives me. And my HIIT workouts have improved my steady-state performance. There's no downside.

But here's another reason I love HIIT for strength: You work your muscles, but you also work at an intensity high enough to give you a first-rate cardio challenge while simultaneously building strength. My patients often ask, "Is this a strength day or a cardio day?" The truth is that when you do HIIT, it's just a day. You're building both strength and cardiopulmonary fitness at the same time. You can do nothing but these workouts a few times a week and get yourself stronger and in great cardiovascular shape. Now that's a comprehensive workout.

Can a 10-Minute Workout Really Deliver Health and Fitness Benefits?

Yes, it can. Research has begun to consistently bear this out: A recent study in the journal PLOS ONE4 had otherwise-healthy obese participants perform 3 minutes of intense intermittent exercise within a 30-minute weekly training time commitment for 6 weeks (three sessions of 10 minutes that included 1 minute of intervals per week). The results: improved oxygen consumption, lower blood pressure, and increased insulin sensitivity. And that was just from adding 1 minute of intense exercise in a 10-minute training window three times a week.

Author

Jordan Metzl, MD, is the author of The Exercise CureThe Athlete's Book of Home Remedies, andDr. Jordan Metzl's Running Strong. He is a nationally known sports medicine physician at New York City's Hospital for Special Surgery. He appears regularly on the esteemed New York Magazine's Top Doctors list. Prior to joining NYC Hospital for Special Surgery, Dr. Metzl completed his fellowship in sports medicine and dance medicine at Harvard Medical School and Boston Children's Hospital. He lives in New York City. View titles by Jordan Metzl