The Life Plan (49 page)

Various formulas based on your age can be used to estimate your individual maximum heart rate, which will vary significantly between individuals. Your HR
_max
is biologically determined and declines as you age. The correlation to age is very strong. If a large number of 20- to 75-year-old fit individuals ran on a treadmill to exhaustion to reach their HR
_max
, the distribution of heart rates would range from approximately 200 bpm (beats per minute) for the 20-year-olds down to 145 bpm for the 75-year-olds. The most common formula used today is:

The generally accepted error in age-predicted formulas is plus or minus 10 to 15 beats per minute, and this is due to different inherited characteristics and levels of fitness. There might be some discrepancy when using the age-adjusted formula, especially for men who have been fit for many years, or older men in their 60s, 70s, 80s, or older.

I believe that heart rate zone training is the best approach to all-around fitness. It works for a 72-year-old athlete like me, a 60-year-old with a family history of heart problems, a 45-year-old wanting to improve strength, or an 80-year-old who wants to be able to take the steps rather than an elevator to his third-floor apartment. It works for a 20-year-old who wants to drop body fat and become fit, a 30-year-old who has become sedentary from too much time in front of his computer, and a 50-year-old who is preparing for his second wedding (and honeymoon) and wants to be at his best.

The heart is a muscle that you can strengthen, just like any other muscle. And just like any other, it’s a use-it-or-lose-it muscle: If you don’t do cardiovascular exercise, your heart will lose its functional ability. Recent research has shown powerful benefits from exercising your heart in different zones, or rates of exercise, to get maximum benefit.

Heart rate zones are expressed as a percentage of your HR
_max
and reflect exercise intensity and the corresponding benefit to your heart. Once you have established your HR
_max
you can calculate your exercise HR for each zone that I have listed below. Your target heart rate (THR) is the desired range of heart rates you need to reach during aerobic training to enable your heart and lungs to get the most benefit from your workout. This range varies depending on your level of fitness and previous training.

Keep in mind that your aerobic capacity (endurance) improves much faster if you train closer to 85 percent rather than 60 percent of your HR
_max
, but some men don’t have the capacity to start training at 85 percent, or they simply prefer to start training at lower values and gradually increase their intensity over time. Other men may even need to start at levels as low as 40 or 50 percent, depending on their age, level of fitness, overall health, and current body weight. The level that you start with isn’t all that relevant. What really matters the most is that you get started and stick with it. Over time, as your endurance improves, you can gradually increase the intensity. Your body accommodates to both low- and high-intensity workouts by increasing the activity of respiratory enzymes and biochemical reactions in your muscles. Before you know it, you will be able to train at 80 percent or more of your target heart rate training zone and actually love it.

I think it is also important to compare your heart rate training zones with your own rating of perceived exertion (RPE). RPE is defined as how hard you perceive an exercise to be while you are doing it. This enables you to create a quantifiable method for guiding your workouts and determining your specific exercise intensity. Once you know what level of RPE you need to maximize your cardio workout, you won’t have to keep checking your heart rate, and you can focus on the rhythm you have created or on the music, TV, DVD, or other interesting (attractive) people in the gym. It doesn’t take long to correlate your heart rates with the RPE scale below. I used the example of the spectrum of standing still to race walking to explain the scale, but you can apply this to any type of aerobic exercise.

Nothing at all, sitting or lying.

Very, very light: standing.

Moderate: walking down the street.

Moderate, no sweating: a brisk walk where you can talk at the same time.

Somewhat hard, moderate-sweat: a fast walk or slow jog.

Moderate hard, vigorous-sweat: very fast walking, jogging, or “power” walking.

Vigorous: running.

Vigorous-strenuous: a fast run.

Strenuous: a very fast run.

Strenuous-severe: maintaining a race pace.

10
Severe: race pace to win, last lap, balls-to-the-wall, can’t wait to stop.

(Source: Modified from G. V. Borg (1982), Psychological basis of perceived exertion.
Medicine and Science in Sports and Exercise
, 14, 377–81. American College of Sports Medicine.)

The following list describes typical training heart rate zones and the rates of perceived exertion (RPE) most people associate with these heart rates. These will help you gauge the quality of your cardio exercise.

—50 to 60 percent of your max heart rate (RPE 2 to 3). This is a good beginner training zone for someone who is out of shape or has existing heart problems.

—60 to 70 percent. This zone will burn more total calories than the warmup zone (RPE 3 to 4). Of the calories that are burned, 85 percent will come from existing body fat.

—70 to 80 percent. This zone will strengthen your heart and is good for those who want to compete in an endurance sport (RPE 5 to 6). Although this zone burns more total calories, only 50 percent of them are derived from body fat and the rest come from glucose stored in your muscles.

—80 to 90 percent. This zone will improve your METs

significantly (RPE 7 to 8). Drastic improvements can be seen in your overall cardio respiratory system, and you will increase your ability to fight fatigue. This zone burns only about 15 percent of its calories from fat during the exercise session, but fat calories continue to be burned for several hours after the session. Train at this level for 15 to 25 minutes to get maximum cardiovascular benefit. Getting to 85 percent of HR

for 2 minutes won’t cut it.

—90 to 100 percent. This zone will burn the highest number of calories and is very intense (RPE 9 to 10). Most men can stay in this zone only for a few seconds to a minute or two at most. There is a high risk of injury when training at this zone.

The most accurate way to calculate your THR is the Karvonen Method, because it factors in your resting heart rate, which is another indicator of your level of fitness. To determine your resting heart rate (HR
_rest
), take your pulse when you are at rest—awake but lying down. The best way to do this is to check it three mornings in a row just after waking up. Add all of them together and divide by three to get your average HR
_rest
. The lower your resting heart rate is the more fit you are. Typical resting heart rates in men are in the 60 to 80 bpm range. Conditioned athletes have resting heart rates below 60 bpm. Lance Armstrong has a resting heart rate around 32 bpm. If you are fit, you should be below 50 bpm.

If your resting heart rate is greater than 75 beats per minute, you are 3.46 times more likely to have a heart attack, and your risk of dying is increased by 19 percent. If you have a low resting heart rate you decrease your risk of dying by 14 percent. These facts are all I need to think about to make sure I don’t miss a cardio session.

Here is an example that will help you calculate your target heart rate training zone based on your resting heart rate.

Here’s an example of a 50-year-old man with a HR
_max
of 170 (220 - 50 = 170) and a HR
_rest
of 60: