Cardio: A Waste of Time and Energy?

February 9th, 2009

Although cardiovascular exercise is extremely popular, it’s a less effective way to exercise in most cases and can even be counterproductive.

The three primary reasons for the popularity of cardiovascular exercise are health, weight loss, and athletic conditioning. Each of these goals have unique characteristics that make cardiovascular exercise a questionable choice for achieving them.

A Matter of Energy Production

There are two primary energy systems that support the demands of physical activity. They are the aerobic and anaerobic energy systems. The anaerobic energy system is able to produce energy quickly, but can only do so for a short period of time. In contrast, the aerobic energy system produces energy at a slower pace, but can sustain production for an extended length of time.

A short burst of intense activity, such as a sprint, will get most of it’s support from the anaerobic energy system while a long jog or walk will only be supported by the aerobic energy system. Because intense activities typically exceed the capabilities of the anaerobic energy system, they often require support from the aerobic energy system as well. However, this doesn’t apply in reverse. Mild to moderate activity never requires support from the anaerobic energy system.

Intense activity trains both the anaerobic and aerobic energy systems while mild or moderate activity only trains the aerobic energy system. This is an important concept to keep in mind throughout the rest of the article.

Exercising for a Healthy Heart

Most people know that aerobic exercise improves cardiovascular health and helps to prevent heart disease. However, many people engage in an excessive amount of cardiovascular exercise that promotes cellular damage and can actually increase the risk of heart disease. In contrast, anaerobic exercise is much more time efficient. It only requires 5 to 10 minutes to complete a thorough workout and is much less likely to promote excessive exercising.

The Twisted Fate of a Marathon Runner

Regardless of the type, exercise is just one small aspect of the healthy lifestyle that plays a much larger role in minimizing the risk of heart disease. The famous American marathon runner Alberto Salazar is an eye opening example of this. He had a heart attack at the age of 49, just one year after running the New York City Marathon. At the time, he was still running regularly and was following a low fat diet.

While most people would blame his heart attack on genetics, I have a much different perspective to share. While genetics may increase the susceptibility of a heart attack, lifestyle factors are still most likely to make the susceptibility a reality.

Excessive exercise causes significant cellular damage, even within arteries. To repair this damage, the body requires a good supply of high quality protein and fat. Yes, I said fat! Alberto Salazar clearly put a tremendous amount of wear and tear on his body during his lifetime. However, by following a low fat diet, he was depriving himself of the nutrients necessary for repair. And because cholesterol plays an important role in the repair of cell damage, the cholesterol lowering medication he was taking may very well have worsened the problem.

High blood pressure is another symptom of the oxidative damage that can result from excessive exercise, and at the time of his heart attack, Salazar happened to be taking blood pressure medication as well. This is a strong indication that his doctors were merely chasing symptoms instead of addressing the the oxidative damage caused by his extremely active lifestyle and the low fat diet that was unable to support it.

In short, don’t make the mistake of thinking that cardiovascular exercise, or any exercise for that matter, will compensate for unhealthy habits. A well rounded healthy lifestyle is always a requirement for optimal health, and this applies to the prevention of heart disease as well.

Continuity Matters Most

In regard to anaerobic versus aerobic exercise, some may argue that one is more beneficial than the other, but the bottom line is that they both can improve your health. The most important aspect of an exercise program is adhering to it, so choose a form of exercise that you enjoy and are likely to stick with long term.

Exercising for Weight Loss

Even though people don’t become overweight because of an exercise deficiency, weight loss is probably the most common reason why people exercise. Despite poor diet being the most significant cause of weight gain, most people address it by going on an exhausting and time consuming calorie burning crusade to prevent their poor diet from increasing their waist size.

As with cardiovascular health, there’s a lot more to weight loss than exercising and burning calories. In fact, if your lifestyle, diet, and health are in order, you can lose all the weight you need to with only a minimal amount of exercise.

Contrary to what most people think, weight gain is not a problem based strictly on calorie consumption. It’s more about quality. Most people simply have far too much sugar and refined carbohydrate in their diet. While some people need more carbohydrates than others, nobody needs the excessive amount that is typical in the modern diet. Furthermore, excessive consumption of sugar and refined carbohydrates is also a serious health risk.

Cleaning up your diet is the most effective and healthy way to control your weight and should take priority over exercise. You can learn more about a healthy diet by reading my article about Metabolic Typing.

Burning Calories and Fat Outside of the Gym

Although a healthy lifestyle is by far the most significant aspect of weight loss, exercise can certainly make it easier. The type of exercise you choose can make a significant difference as well. Most people become a slave to calorie burning and spend hours on cardio machines. Not only can this be mind numbingly boring and a major investment of time, but it also puts significant wear and tear on your body. By doing this, you’re basically trading time and health for burned calories and it doesn’t have to be this way.

Intense anaerobic activity stimulates a process called excess post-exercise oxygen consumption (EPOC). In simple terms, after you’ve stopped exercising, the body continues to sustain an elevated level of metabolic activity that can last up to a few days. Even after just 5 minutes of intense training, you’ll continue burning calories and fat for hours which can have a significant impact on your weight loss. This effect is unique to intense activity and is not stimulated by the mild or moderate exercise that most people engage in.

Lose Fat, Not Muscle

Most people who want to lose weight also want to look good. Muscle looks good, skin and bones doesn’t. Slaving a way on a cardio machine is likely to result in the breakdown of muscle tissue to help meet the excessive energy demands you’re imposing.

Would you rather look like a sprinter or a distance runner?

Exercising for Athletic Conditioning

Athletic performance is probably where the difference between anaerobic and aerobic training has the most significant impact.

Common sense dictates that most of your training should closely resemble competition. For this to happen, it’s essential to understand the energy demands of your sport. Sprinting is obviously an anaerobic sport while distance running or cycling are obviously aerobic or endurance sports. But what about most of the other sports that fall somewhere in between? When making this assessment, most people place too much importance on the duration of competition and failing to realize that the duration of actual activity represents less than half of this time.

A Case Study: Tennis

Tennis is an excellent example of a sport with energy requirements that aren’t so obvious. For a recreational player, a typical match lasts between 1 and 2 hours. Although uncommon, a long match might last up to 3 hours. Professional tennis matches are about the same with the exception of men’s grand slam matches which require winning at least 3 sets instead of 2. Some of the longest grand slam matches have gone well beyond 4 hours, but this is rare.

4 hours is a long time to be playing tennis! Even under the conditions of a short 2 hour match, it’s easy to consider tennis as an aerobic sport. Let’s look at some statistics to make a better judgement.

2009 Australian Open Semifinals

While watching this year’s Australian Open final between Roger Federer and Rafael Nadal, which you can read more about here, the announcers discussed some interesting statistics that compared the energy expenditures of these two players during their semifinal matches.

Nadal vs. Verdasco Federer vs. Roddick
Match Duration 5h 14m 2h 7m
Miles Run 2.13 0.93
Shots Hit 1,473 684

Rafael Nadal probably runs and hits more balls than any other player on tour. If there’s a player that could justify tennis being an aerobic sport, it would be him. Furthermore, his semifinal match was the longest match in Australian Open history!

According to these statistics, Nadal ran 2.13 miles in 5 hours and 14 minutes. This is basically as much as a tennis player will ever run in a single match. To put this in perspective, a good runner can run this distance in just 10 minutes! Aerobic endurance sports are characterized by moderately intense activity that’s sustained continuously for a long period of time. Suggesting that 10 minutes is a long period of time is quite a stretch.

Now consider that Federer ran only 0.93 miles in his match, and his 2 hour match is far more typical than Nadal’s 5 hour match. A good runner can cover this distance in about 5 minutes. That’s certainly not a long period of time.

Length of Actual Play

Here are a few more statistics to consider that further support the argument of tennis not being an endurance sport. The following two matches confirm that the actual amount of time the players are actually playing is significantly less than the entire match duration.

1993 French Open final between Jim Courier and Sergei Bruguera:
Duration of match: 3 hours and 59 minutes
Duration of actual play: 15 minutes

1992 Wimbledon final between Andre Agassi and Goran Ivanisevic
Duration of match: 2 hours and 50 minutes
Duration of actual play: 34 minutes

The short duration of actual playing time is even more significant when you consider the fact that these were both 5 set matches.

Tennis is Explosive

In contrast to an aerobic endurance sport, anaerobic sports are characterized by quick explosive movements. Even the more defensive players put a tremendous amount of energy and explosiveness into most of their shots. And regardless of playing style, they have to be extremely quick and explosive off their feet just to get to the opponent’s shot.

The quick and explosive movements required in tennis have no resemblance to the moderate and continuous movement that characterize most endurance sports. Despite this, many tennis players train as if they’re an endurance athlete. As I said earlier, it makes most sense to train the way you compete, and tennis players certainly can’t rely on a casual jog to get to their opponent’s next shot!

Don’t Train to be Slow

Muscle is composed of three different types of fibers: fast twitch, slow twitch, and intermediate. Fast twitch fibers are the ones that facilitate the explosive and powerful movements that are required in sports like tennis. An individual’s composition of muscle fiber is determined by genetics, and as you would guess, the most explosive athletes are genetically gifted with a higher percentage of fast twitch fibers.

However, it’s important to realize that the function of intermediate fibers can adapt and more closely resemble either of the other two fiber types. For obvious reasons, it’s in the best interest of a tennis player to have as much fast twitch capability as possible. Endurance training encourages the intermediate fibers to transition more toward slow twitch, and in effect, reduces an athlete’s capacity to be explosive. As such, a tennis player that trains for endurance is also training to become slower and less powerful!

Tennis Players Also Need Endurance

Although sports like tennis rely heavily on power and quickness, many people will argue that endurance is still important. This is absolutely true, but you don’t need to train specifically for endurance to achieve it!

As I said in the beginning of this article, if you train the anaerobic energy system properly, it will have a carry over effect that will train the aerobic energy system as well. Research shows that high intensity interval training produces an increase in aerobic capacity that is comparable the effects of endurance training. But unlike endurance training, interval training also improves anaerobic capacity, saves a lot of time and energy, reduces the amount of wear and tear on the athlete, and avoids the risk of provoking intermediate muscle fibers to transition toward slow twitch behavior.

What Exactly is High Intensity Interval Training?

High intensity interval training is nothing more than multiple short bursts of intense activity that are alternated with rest periods. For example, you can run on a treadmill near top speed for 30 seconds, rest for 2 minutes, and repeat this for a total of 5 to 10 times. You can also use a stationary bike, an elliptical machine, or even better, you can run on a track or a football field. Regardless of the activity, it’s the high intensity and short duration that’s important.

Because everyone recovers from each interval at a different rate, using a heart rate monitor will make it much easier to establish ideal rest periods. An insufficient rest period will reduce your capacity for the next interval while an excessive rest period will reduce the stimulus of the training. Either effect is undesirable and using a heart rate monitor can prevent both of them. As a general guideline, you can start with a rest period that lasts until your heart rate drops to 120 or 125 and make adjustments as you see fit.

For athletes, another way to increase the effectiveness of interval training is to incorporate sport specific movements into the intervals. For example, Tennis requires a lot of direction change and sophisticated footwork. Incorporating these movements into the intervals will save time and energy by training movement and conditioning at the same time.

Getting Started With Interval Training

Intensity is a relative term. Some people are highly conditioned and can sprint at full speed without any problems while others become heavily winded after walking up a flight of stairs. Likewise, a simple warm up routine for an elite athlete may be the equivalent of an intense workout for someone who is sedentary.

If you’re already active, particularly if you’re an athlete, you’ll know you’re doing interval training correctly when you’re hunched over and gasping for air. Interval training may not consume much time, but if done properly, it’s hard work!

If you’re out of shape, don’t overdo it! You can still benefit from interval training without the risk of hurting yourself. As I said, intensity is relative. Start out with a level of intensity that is challenging for you. Perhaps that means 30 seconds of brisk jogging or climbing a few flights of steps. You can increase the intensity gradually as you become more comfortable with your capabilities.

With proper respect given to an individuals capacity for intensity, interval training is something that can benefit anyone regardless of age or ability. If you’re unsure of how to incorporate it into your lifestyle in a way that promotes health and is safe for your current level of fitness, I highly recommend reading PACE: The 12-Minute Fitness Revolution by Dr. Al Sears.

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