What is Your Target Heart

In order to figure out which zone you're in, you first need
to figure out what your own target heart rate is. You can do this by using the Karvonen Formula.
You can also use any number of target heart rate calculators to get your heart rate zone, but many of them do not incorporate your resting
heart rate (which makes it a bit more accurate).

Below is an example for a 23-year-old person with a resting
heart rate of 65 beats per minute (*to get your resting heart rate, take your
pulse for one full minute.):

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220 - 23 (age) = 197
197 - 65 (resting heart rate) = 132
* 65% (low end of heart rate) OR 85% (high end) = 85.8 OR 112.2
85.8 + 65
(resting heart rate) = 150 112.2 + 65 (rhr) = 177
The target heart rate zone
for this person would be 150 to 177. For this person to work in her 'fat
burning' zone, she would need to stay around 150 beats per minute or lower. To
work within her 'cardio' zone, she would need to work at 150 bpm or

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Zone 1 THE HEALTHY HEART ZONE: 50%-60% of your individual
Max HR

This is the safest, most comfortable zone, reached by
walking briskly, swimming easily, doing any low intensity activity including
mowing your lawn. Here you strengthen your heart and improve muscle mass while
you reduce body fat, cholesterol, blood pressure, and your risk for
degenerative disease. You get healthier in this zone, but not more aerobically
fit -- that is, it won't increase your endurance or strength but it will
improve your health.

Zone 2 THE TEMPERATE ZONE: 60% to 70% of your individual
Max HR.

It's easily reached by going a little faster like increasing
from a walk to a jog. While still a relatively low level of effort, this zone
starts training your body to increase the rate of fat release from the cells to
the muscles for fuel. Some people have erroneously called this the "fat
burning zone" because up to 85 % of the total calories burned in this zone
are fat calories. Rather, we burn fat in all zones.

Zone 3 THE AEROBIC ZONE: 70%-80% or your individual
Max HR

In this zone -- reached by running moderately as an
example -- you improve your functional capacity. The number and size of your
blood vessels actually increase, your lung capacity and respiratory rate, and
your heart increases in size and strength so you can exercise longer before
becoming fatigued. You're still metabolizing fats and carbohydrates but the
ratio has changed - about a 50-50 rate, which means both are burning at the
same ratio.

Zone 4 THE ANAEROBIC THRESHOLD ZONE: 80%-90% of your
individual Max HR

This zone is reached by going hard -- running faster. Here
you get faster and fitter, increasing your heart rate as you cross from aerobic
to anaerobic training. At this point, your heart cannot pump enough blood and
oxygen to supply the exercising muscles fully so they respond by continuing to
contract anaerobically. This is where you "feel the burn." You can
stay in this zone for a limited amount of time, usually not more than an hour.
That's because the muscle just cannot sustain working anaerobically (this means
without sufficient oxygen) without fatiguing. The working muscles protect
themselves from overwork by not being able to maintain the intensity level.

Zone 5 THE REDLINE ZONE: 90% to 100% of your individual
Max HR.

This is the equivalent of running all out and is used mostly
as an "interval" training regiment -- exertion done only in short to
intermediate length bursts. Even world-class athletes can stay in this zone for
only a few minutes at a time. It's not a zone most people will select for
exercise since working out here hurts, there is an increased potential for
injury but you burn lots of calories, mostly carbohydrates.

Heart Rate Facts:

Heart rate increases at high temperatures. Your heart rate is higher when running on a hot
day. As the temperature increases from 60 degrees to 75 degrees, a athlete's
heart rate at a given speed increases by about two to four beats per minute.
When the temperature increases from 75 degrees to 90 degrees, you can expect
your heart rate running at a given speed to increase by approximately ten beats
per minute. High humidity magnifies the effect of high temperatures on heart

To gain the same benefits as on a cool day, you
should increase your heart rate zones by two to four beats per minute when the
temperature is in the 70s and the humidity is low. On a high humidity day in
the 70s or a low humidity day in the 80s, you should increase your zones by
approximately five to eight beats per minute to correct for the heat factor. In
more extreme conditions, such as a high humidity day over 80 degrees, you
cannot accurately adjust your heart rate zones for the conditions. On the most brutal
summer days, it is wise to adjust your training schedule to avoid high
intensity training.

Dehydration causes an increase in heart rate. When you become dehydrated, your blood volume
decreases and less blood is pumped with each heartbeat. Your heart rate at a
given running speed, therefore, increases. A 1992 study by S.J. Montain and Ed
Coyle, Ph.D., found that heart rate increases approximately seven beats per
minute for each 1% loss in body weight due to dehydration. For example, if you
weigh 150 pounds, when you lose 1.5 pounds due to dehydration your heart rate
at a given running speed would increase by about seven beats per minute. Water
loss of this magnitude occurs after an hour of running on a mildly warm day. On
a hot day, runners typically lose over two pounds of water per hour. If you set
heart rate training zones when properly hydrated and then become dehydrated
during training, your pace will decrease as you become progressively more
dehydrated. Dehydration can also
be a sign of on-coming fever, illness or infection.

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Heart rate during running varies by a few beats from
Several studies have found
that heart rate during running at a given pace varies by a few beats per minute
from day-to-day. It is not clear why this occurs, but most physiological
variables exhibit similar amounts of day-to-day variation. This means that if
you monitor your heart rate religiously, you will find that some days it
appears you are getting slightly fitter and other days it appears you are
getting out of shape, when in fact, your fitness level may not be changing. You
should be cautious, therefore, in interpreting the results of any one session
of heart rate monitoring. Do not put too much emphasis on small changes of two
to three beats per minute in heart rate found during one run. When you find a
systematic reduction in heart rate at a given pace, however, you can be
confident that your fitness has improved. Similarly, if you find that your
heart rate is consistently higher than expected, you can confidently conclude
that something is wrong; i.e. you may be losing fitness or—more likely for most

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Heart rate variability (HRV) is the variation of beat-to-beat intervals. A healthy heart has a large
HRV, while decreased or absent variability may indicate cardiac disease. HRV
also decreases with exercise-induced tachycardia. HRV has been
the focus of increased research to use it as a physiological marker to classify
different pathological disorders.

One aspect of heart rate variability can be used as a
measurement of fitness, specifically the speed at which one's heart rate drops
upon termination of vigorous exercise. The speed at which a person's heart rate
returns to resting is considerably faster for a fit person than an unfit
person. A drop of 20 beats in a minute is typical for a healthy person. A drop
of less than 12 beats per minute after maximal exercise has been correlated
with a significant increase in mortality.

Maximum heart rate (also called MHR, or HRmax) is the maximum heart rate that a person
should achieve during maximal physical exertion. Research indicates it is most
closely linked to a person's age; a person's HRmax will decline as
they age. Some research indicates the speed at which it declines over time is
related to fitness—the more fit a person is, the more slowly it declines as
they age.

HRmax is utilized frequently in the fitness
industry, specifically during the calculation of target heart
when prescribing a fitness regimen. A quick way to estimate MHR
is to subtract your age from 220, but HRmax can vary significantly
between same-aged individuals so direct measurement using a heart rate monitor (and
with medical supervision or at least permission and advice) should be used by
those seeking maximum safety and effectiveness in their training. People who
have participated in sports and athletic activities in early years will have a
higher MHR than those less active as children.

Measuring HRmax

The most accurate way of measuring HRmax for an
individual is via a cardiac
stress test
. In such a test, the subject exercises while being
monitored by an electrocardiogram (ECG). During the test, the intensity of exercise is periodically increased (if
a treadmill is being used,
through increase in speed or slope of the treadmill) until the subject can no
longer continue, or until certain changes in heart function are detected in the
ECG (at which point the subject is directed to stop). Typical durations of such
a test range from 10 to 20 minutes. Since the HRmax declines with
age, this test does not hold permanent value.

Conducting an accurate maximal exercise test requires
expensive equipment, and should only be performed in the presence of medical
staff due to risks associated with high heart rates. Instead, people typically
use predictive formulae to estimate their individual Maximum Heart Rate. The
most common formula encountered is:

HRmax = 220 − age

Target heart rate

Target heart rate (THR), or training heart rate, is a
desired range of heart rate reached during aerobic exercise that
enables one's heart and lungs to receive the most
benefit from a workout. This theoretical range varies based on one's physical
condition, age, and previous training. Below are two ways to calculate one's
Target Heart Rate. In each of these methods, there is an element called
"intensity" which is expressed as a percentage. THR can be calculated
by using a range of 50%–85% intensity.

Basal Metabolic Rate (BMR)

Basal Metabolic Rate is the minimal caloric
requirement needed to sustain life in a resting individual. This is the
amount of energy your body would burn if you slept all day (24 hours).
Let's look at some factors that affect BMR:

Age: In youth,
the BMR is higher; age brings less lean body mass and slows the BMR.

Height: Tall,
thin people have higher BMR's.

Children and pregnant women have higher BMR's.

Body Composition:
The more lean tissue, the higher the BMR. The more fat tissue, the
lower the BMR.

Fever: Fevers
can raise the BMR.

Stress: Stress
hormones can raise the BMR.

Environmental Temperature: Both the heat and cold raise the BMR.

Fasting/starvation hormones lower the BMR.

Malnutrition: Malnutrition
lowers the BMR.

Thyroxin: The
thyroid hormone thyroxin is a key BMR regulator; the more thyroxin produced,
the higher the BMR.

Ways to measure BMR:

General Calculation: BMR = your body weight in lbs x
10 kcal/lb

Ex. Subject weighs 150 lbs

BMR = 150 x 10
kcal/lb = 1,500 kcals

The E-Z Version!

Max Heart Rate = 220-age.

You want to train at 70-80% of your Max Heart Rate.

In order to lose weight you need to figure out your BMR
(Basal Metabolic Rate).

BMR = body weight X .10

BMR / 6 = the number of calories you should take in for six
small meals a day.

The human stomach is most efficient when digesting 10-12oz
per sitting or every 2 hours (i.e. 6 meals a day).

Measuring your success:

A body fat scale-numerous scales are out there. They are
surrounded by controversy but a scale is a scale. Use it as a gauge to see how
far you've come.

Simply measure your mid-section periodically (every 30 days
according to Iron90).

Get your body fat measured periodically by a professional

As long as you take in the number of calories dictated by
your BMR and exercise at 70-80% of your Max Heart Rate and you will lose
fat. Your body will have to rely
on it's own stores.

Ex: BMR = 1500. You eat 1500 calories per day with 6 meals a
day. You exercise daily using your
TIMEX Heart Rate monitor that calculates calories burned. Your body will have to provide energy
for that exercise time (calories) with it's own stores of fat! Hence, your body fat decreases!

What do you think?