Have They Found the Perfect Interval Formula?

In the fitness world, buzzwords come and go almost monthly. One that seems to have some real staying power, though, is high intensity interval training, or HIIT. Although it’s not really a new idea, HIIT has really gained ground in the past few years with the rise of standardized forms like Crossfit, Tabata and the Little method. Even with these programs, though, a universal formula for an effective HIIT workout has been sorely lacking.

A group of Danish researchers set out in 2012 to define the perfect formula for HIIT and their work produced some intriguing results worth considering.

The 10-20-30 Study

At the beginning of their research, the team, led by Dr. Thomas Gunnarsson experimented with different ratios that are already at use in other HIIT methods.

Starting with 30-second sprinting bouts, which is a common approach, they found that, although this produced powerful results in their subjects, it’s also a very demanding. Eventually, through trial-and-error, the team fell on 10-second intervals.

It’s not really surprising that the 10-second sprints produced benefits but the exact depth of those improvements has caught many experts off-guard.

Over the course of the 7-week study, veteran 5K runners cut a full minute off their time and 1500-meter runners reduced their time by an average of 23-seconds. And these reductions all happened while slicing their weekly mileage by half. As an added selling-point, these highly effective workouts only took about 20 to 30 minutes.

Workout Details

At its core, the 10-20-30 program is modeled after the Fartlek approach by involving short bursts of running with the speed adjusted by how you’re feeling.

A typical workout following this new protocol would look like this:

  1. A 10-minute warmup. The runners in the original study ran just 3/4 of a mile for their warmup, with no regard to time.
  2. Jog for 30 seconds, run for 20 and then sprint for 10. Repeat this same pattern four more times, follow this routine for five straight minutes.
  3. Walk or jog for 2 minutes as an active rest.
  4. Repeat steps 2 and 3. Cycle through these intervals two or three times. Runners in the study eventually worked their way up to four of these sets.

The original study didn’t list any sort of cool-down but a 10-minute walk is generally recommended to wrap-up your workout.

Because this approach allows you to adjust the speed of each interval, whether it be jogging, running or sprinting, and the number of times you repeat the pattern, it’s easily adapted to your fitness level.

Expert Reception

In general, most experts who reviewed the research found no problems with the study methodology or the program that the study produced. A few authorities have questioned the effectiveness of this type of workout for elite-level athletes.

Others have expressed doubts regarding the trustworthiness of the touted benefits since the subjects used were all experienced runners. These detractors feel that those benefits are to be expected by runners who suddenly shift to an easier training method.

Overall, however, both anecdotal and expert reports have supported the use of 10-20-30 intervals.

Have you been able to incorporate 10-20-30 into your workouts? Please share your experience in the comments.

Sources

http://www.acefitness.org/certifiednewsarticle/2944/have-researchers-discovered-the-ideal-hiit-formula

http://www.ncbi.nlm.nih.gov/pubmed/22556401

The Glycemic Index: What You Should Know

Your body is full of delicate balancing acts. Different chemicals are constantly competing to counteract each other and keep things running smoothly, in a process clinically known as homeostasis. This ability to self-regulate allows our bodies to maintain a healthy temperature, blood pressure and water levels. Another important example of homeostasis that has been receiving a lot of attention lately is blood sugar, or blood glucose.

Many diet programs utilize the glycemic index, a measure of how food affects your blood sugar levels, to achieve certain health benefits. How is blood sugar naturally controlled? How does food affect our blood sugar? What benefits can you expect from monitoring the glycemic index of your diet?

How Blood Sugar Works

Sugar, in the form of glucose, is used throughout your body as fuel at the cellular level. Generally, a healthy level of glucose in your blood is between 90 and 110 mg/dl, which ensures your cells have all the fuel they need to get their job done without being damaged. These levels are maintained by two hormones, insulin and glucagon, both released by the pancreas.

Insulin is the weapon of choice when blood sugar levels are too high. Once it’s in the bloodstream, insulin makes the cells absorb more sugar and tells the liver to store some for later use. This pulls the sugar from the blood and stops any potential damage.

Glucagon is released when blood sugar levels are too low and basically undoes the effects of insulin. This hormone signals to the liver that it’s time to release stored glucose into the blood, raising sugar levels.

When you eat, the carbohydrates in your food are broken down into sugar, which causes a spike in your blood sugar levels. In response, your body begins the cycle of insulin and glucagon to try to regain balance. The varying effects of food on your blood sugar is called the glycemic index (GI). Foods with a high GI are absorbed rapidly, making your blood sugar shoot up quickly and then plummet when insulin is released. Low GI foods digest slower and do not have such a drastic effect on your blood sugar.

Can It Help You Lose Weight?

Various diets attempt to control your blood sugar levels by means of this glycemic index, focusing on foods with a low GI that will have little effect on your blood sugar.

Although this type of diet is beneficial for people with blood sugar issues, diabetes or other related conditions, it is frequently used for weight loss. By nature, this diet will limit your intake of high-carb foods since these typically have a high GI. Compared to other low or no carb diets, though, a glycemic index diet is generally easier to follow because you don’t have to count carbs. This accessibility and sustainability make a glycemic index diet attractive. But does it work?

Lab results are mixed. Some studies have shown no more weight loss from following a GI diet than from following any other program, while others demonstrate a much higher potential for weight loss. Part of the problem could be the wide variation in GI diets leading to an inconsistency in testing. Usually, however, the GI diets that do cause weight lose encourage high fiber and protein intake which contributes to lower portions.

If you do plan on following a GI diet, Dr. David Katz, writing for U.S. News, stresses the importance of using the GI only for its intended purpose: measuring the effects of carbohydrates on blood sugar. Katz points out that these diets pay no attention to other vital nutrients like protein, fats and fiber and paint an unbalanced view of nutrition.

For weight loss, the GI can be incredibly useful to help you decide which carbohydrates to eat, but should be used in conjunction with a balanced diet.

Performance Enhancing Potential

Because carbohydrates are the main fuel used during endurance training, it seems logical that a high GI drink during exercise would be useful. However, a 2009 study published in the Journal of Science and Medicine in Sport found no difference in performance from high or low GI drinks. The researchers did note, though, that a low GI meal before exercise lessened the effects of cortisol, which causes your body to store fat.

Have you followed a glycemic index diet? Please share your experience with us in the comments.

Sources

http://www.pc.maricopa.edu/Biology/pfinkenstadt/BIO201/201LessonBuilder/UnitOne/Homeostasis/index.html

http://www.mayoclinic.com/health/glycemic-index-diet/MY00770

http://health.usnews.com/health-news/blogs/eat-run/2012/10/18/use-and-abuse-of-the-glycemic-index

http://www.ncbi.nlm.nih.gov/pubmed/18789762

Why napping is good for you

I grew up in a family of nappers. In fact, my dad used to joke that his second job was mattress testing since he spent much of his leisure time resting on one.

Turns out he was onto something. And so are the Spanish and other cultures who believe in the siesta, a little afternoon respite to repower the synapses and get the juices flowing again.

Napping is wasted on the young — half the time they’d rather not be doing it. Many adults, on the other hand, welcome a good nap as often as possible (at least I know I do). Yet in our busy, type-A society, where everyone feels they need to do 12 things at once, napping has gotten a bad rap.

I say it’s time to change that view, especially in a world where so many people are sleep-deprived. According to the National Sleep Foundation, a short nap of 20-30 minutes can help to improve mood, alertness and performance without leaving you groggy or interfering with your nighttime sleep (if it’s not too late in the day). In fact, one study found that a 20 minute nap is actually more effective than either 200 mg of caffeine or a bout of exercise.

Remember, many of the world’s great thinkers and leaders have been regular nappers, including John F. Kennedy, Winston Churchill and Napoleon. It apparently worked for them.

Sara Mednick, assistant professor in the Department of Psychology at the University of California, Riverside, and author of “Take a Nap! Change Your Life,” says that without a midday nap many people are unable to perform at optimal levels throughout the day. She’s conducted studies in conjunction with numerous academic institutions and the U.S. Navy to prove that a short power nap every afternoon when you begin to flag is a great way to get you through the rest of the afternoon and evening. It’s especially recommended for tired drivers —who are a real danger on the road. Sleep experts recommend that if you feel drowsy while driving, you should immediately pull over to a rest area, drink a caffeinated beverage and take a 15-30 minute nap.  Soon you’ll be safely back on the road.

If all this wasn’t enough to encourage you to take a nap, Mednick also says that napping boosts creativity, reduces stress, enhances libido, aids in weight loss, keeps you looking younger, reduces the risk of heart attack, strengthens memory, clarifies decision-making, and improves productivity. It also feels great.  I don’t know about you, but sign me up!

So instead of thinking about a napper as a lazy, unambitious soul who’s slacking off, perhaps we should consider him or her a smart worker who knows when he or she needs a break to be their best.

For those who aren’t freelancers like myself working next to their beds — perfect for procrastinating and nap-taking — there may still be ways to slip in some mid-day sleep. You can always do a George Costanza (from a famous Seinfeld episode) and crawl under your desk to nap unnoticed, or shut your door, lean back in your chair or lay your head on your desk. I can sleep anywhere, but if that doesn’t work for you, you might try slipping away to your car on your lunch break.

There are even a few very progressive companies (like Google and Huffington Post) that offer “nap rooms,” demonstrating that they truly get the benefits for their employees. But if it’s against office policy, save your napping for the weekends!

If you’re worried you’ll nap the afternoon away, set a timer on your cell phone for just a brief break. You’ll be renewed, refreshed and raring to go after a power nap. So forget the latte or energy drink; grab a few zzzzs and let me know how great you feel afterwards.

How often do you nap, and how does it make you feel?

Sources:

Take a Nap! Change Your Life, by Sara Mednick (Workman Publishing Company)

http://www.sleepfoundation.org/article/sleep-topics/napping

http://well.blogs.nytimes.com/2011/10/31/really-the-claim-for-a-more-restful-nap-avoid-caffeine/

http://www.health.harvard.edu/newsletters/Harvard_Health_Letter/2009/November/napping-may-not-be-such-a-no-no

Fitness Myths: Spot Training

One of the most common fitness myths is spot training, sometimes called spot reduction. Spot training is the idea that you can cause weight loss or muscle definition in one area without affecting other parts of the body. This myth is particularly persistent because everyone wants it to be true. Everything would be so much easier if only the infomercials promising “rock hard abs” and “buns of steel” — after just a few minutes with a specific product — were telling the truth!

What’s the science behind spot training being labeled as a myth? And how can you achieve real and healthy muscle definition?

How Muscle and Fat Work

Understanding how both fat and muscle function will help you understand why spot training is anatomically impossible. Fat makes up a layer between your muscles and your skin. Although it is true that fat is used as fuel during exercise, your body doesn’t care where the fat it burns for fuel comes from — and muscles do not take fuel from just the fat immediately around them. Weight loss is a result of total body metabolism. Often, factors that are beyond your control, such as genetics, determine where on your body you will lose weight first.

Muscle definition, then, is a balance of muscle growth and weight loss. When people dedicate themselves to one form of training or focus all of their efforts on one muscle group, they are doing themselves a great disservice. For example, many people set out to have “six pack abs” and commit themselves to doing enormous amounts of situps. This will give them very strong and large abdominal muscles, but unless they change their diet and lose the fat that obscures those muscles, the six pack will never be visible.

What Science Says

There are no reliable studies that support the idea of spot training. There are, however, several that discredit it. One of the most well-constructed studies to provide evidence against the concept of spot training was conducted by researchers at the University of Massachusetts in the 1980s. During the 27-day program, 13 male subjects were required to perform 5000 sit-ups. Fat biopsies were taken from the subjects’ abdomens, buttocks and upper backs before and after the study. Although the subjects only trained their abs during the course of the study, the results showed that fat decreased similarly at all three test spots.

In commenting on this study, the American Council on Exercise (A.C.E) suggested that these results highlight a possible reason why spot training sometimes seems to occur. When the exercise is difficult enough to burn a significant amount of calories, weight loss occurs evenly around the body — including the target area.

How to Really Tone Up

The spot training myth can become a discouraging stumbling block for people who want to increase their muscle definition. Although it’s not possible to tone just one specific area or muscle group, it is very possible to increase your overall muscle definition. Doing so is simply a matter of decreasing the amount of fat on your body, while increasing the amount of muscle.

One extremely effective method for accomplishing this balance is circuit training. This workout method involves a fast-moving strength workout that incorporates every muscle group, with no rest between exercises. This keeps your heart rate up, working your cardiovascular system much more than traditional strength training.

Spot training is a fitness concept that is simply not supported by any scientific evidence. Don’t let that discourage you, though: you can safely and realistically achieve a lean, defined body through a balanced routine of diet and exercise.

For information on other fitness myths see Seven Fitness Myths Busted.

What has helped you lose weight and increase your muscle definition? Please share it in the comments!

Sources

http://www.exrx.net/WeightTraining/Myths.html

http://www.acefitness.org/fitnessqanda/fitnessqanda_display.aspx?itemid=341

Strength and Cardio Training: Should They Mix?

Strength and cardiovascular training methods are often at odds. Many people train in strictly one or other, believing that the neglected training style will somehow hinder their progress. Gym myths and misunderstandings just add to the confusion, promoting ideas like “running burns muscle.” Other exercisers simply don’t know how to incorporate both strength and cardiovascular training into their schedule and favor the one they enjoy the most.

Should these two training styles be used together? How?

Myths and Misunderstandings

Usually, people practice cardio because they want to lose weight and lift weights because they want to gain muscle. However, two persistent— and incorrect — ideas have pervaded gyms around the world, deepening the divide between strength training and cardio workouts.

Some people who hope to slim down avoid lifting weights, because they are afraid it will make them too bulky. The truth is that muscle growth is a very slow process, and it requires a well designed program of diet and exercise to be followed for years before you appear “bulky.” On the contrary, proper weight training will increase the strength and endurance of your muscles, which will improve your cardiovascular efficiency and burn more calories and fat in the process.

On the other hand, weightlifters who are looking for bulk tend to fear that cardio burns muscle. This one is more of an oversimplification than an outright myth. It is true that, in extreme cases of over-training, your body will begin to use muscle for fuel. However, your body will only go catabolic, as this is called, when you exercise at a high intensity for more than 45 minutes, exercise every day, or exercise on an empty stomach. Put simply, cardio will only burn muscle when you give it no other choice. Balance, in your training and in your diet, will prevent muscle loss.

A healthy combination of strength and cardio training will allow your body to perform at its best, letting the two systems complement each other rather than compete.

How to Do It Right

Understanding that cardio and strength training don’t cancel each other out is only half the battle: now you have to balance the two properly. Mixing cardio and strength training requires a highly individualized approach based on your goals, body type and chosen sport.

First, you should decide whether your focus is to lose weight or gain muscle. Trying to do both at the same time will most likely slow your progress and frustrate you, and may even lead to over-training injuries. Again, this does not mean that you are choosing one training method over the other; the key is to make them work together.

If your primary goal is to gain muscle, then you should lift three times per week, with two moderate-intensity cardio sessions of about 20 to 30 minutes each on your off days. Lifting and running on the same day not only takes more time, it increases your risk of overworking your muscles, which is exactly what you want to avoid.

Next, you need to consider your body type. Is it easy for you to lose weight or does it feel like a constant struggle? Are you naturally muscular? Your body’s natural tendencies will have a strong bearing on your workout plan. For example, an endomorph —  someone who is natural heavy-set — will need to schedule more cardio days to lose weight, but will likely find it easy to gain muscle with plenty of stored fuel in the body.

Lastly, we need to consider your sport. An endurance athlete, for instance, such as a marathon runner, will need a completely different skill-set than a football player. While both of these examples lean towards either cardio or strength, these athletes can still benefit from both modes of training.

As is the case with many aspects of fitness, balance is the key to mixing both cardio and strength training into your routine. While these two modes of exercise are frequently considered incompatible, when scheduled properly, they will work together to help you reach your fitness goals.

Have any tips on mixing strength and cardio training? Please share them in the comments!