Advice
Advice :: Training :: Cardiovascular
Cardiovascular fitness training, also known as aerobic training, is sustained exercise involving the large muscle groups. This exercise should increase the heart rate to a designated range called the target heart range or exercise heart range. Sometimes you will see the terms "rate" or "range" used interchangeably but "range" is generally a scope of numbers which encompass the more specific "rate," which is usually one number. It is difficult to maintain and remain at one specific heart rate number. A range allows an individual to readily monitor his/her own target heart rate while exercising i.e as long as your within a certain range of rate values, you are exercising with net benefit.
Some good examples of cardiovascular fitness activities include, but are
not limited to, brisk walking, biking, running, swimming, cross country skiing,
in-line skating, aerobic dance, and stepping. It does not matter if you do
your workout indoors or out, on a machine or not. It doesn't even matter
if you do a variety of different cardiovascular workouts; this is called “cross-training” and
it is an effective way to vary your cardiovascular workouts.
The bottom-line
goal is to raise your heart rate to your target range, keep it there for
thirty minutes, and do this at least three times per week. Make sure if you
are doing an activity like swimming or in-line skating, that your skill level
is sufficient enough to allow you to do a proper cardiovascular workout.
Start/stop activities, such as tennis, racquetball, and basketball, are great
supplemental workout fun, but do not provide enough sustained time in the
target heart range to be used as your primary means of cardiovascular fitness.
Some
research has suggested periods of five or ten minutes of cardiovascular training
can give the same benefits as longer sessions. However, we still recommend
thirty minutes of sustained cardiovascular exercise three times per week as
the best minimum for most people. This minimum is recommended only after safely
building to this level. Of course, short periods of sustained exercise are
better than doing nothing, but crying “I don't have the time” as
an excuse for doing shorter workouts, we believe, is lacking in substance.
Surely we can all find thirty minutes three times a week to invest in our
health!
Your target heart range is most accurately calculated in a laboratory
setting but this is not feasible for the general public. Using a general formula
(see article below), you can calculate your target heart range using your
age, resting heart rate, and approximate fitness level. It is important to
note that general guidelines based solely on a person's age and fitness level
are guidelines only. These guidelines are frequently posted in health clubs
and on fitness equipment.
It is best to calculate your own target heart range
using your individual resting heart rate since resting heart rates can vary
significantly even among people of the same age. Many factors such as hereditary
tendencies, medical conditions, and even common medications can affect one's
resting heart rate.
The following is a recent article which was published
in the New York Times. We have included it here as not only does it include
the newest general formula for calculating you maximum heart rate, but it
will hopefully help clarify to you that this whole idea is open to much debate.
So, when using these methods to monitor fitness levels, as stressed earlier,
one should only use it as a general guideline. We believe fitness is best
measured as a function of recovery and how low your resting heart rate is.
Simply put, the quicker you recover to a low RHR, the more fit you are.
Article
Maximum Heart Rate Theory Is Challenged
The formula became
increasingly entrenched, used to make graphs that are posted on the walls of
health clubs and in cardiology treadmill rooms, prescribed in information for
heart patients and inscribed in textbooks. But some experts never believed
it.
Dr. Fritz Hagerman, an exercise physiologist at
Ohio University, said he had learned from more than three decades of studying
world class rowers that the whole idea of a formula to predict an individual's
maximum heart rate was ludicrous. Even sillier, he said, is the common notion
that the heart rate is an indication of fitness.
Some people get blood
to their muscles by pushing out large amounts every time their hearts contract,
he said. Others accomplish the same thing by contracting their hearts at fast
rates. As a result, Dr. Hagerman said, he has seen Olympic rowers in their
20's with maximum heart rates of 220. And he has seen others on the same team
and with the same ability, but who get blood to their tissues by pumping hard,
with maximum rates of just 160.
"The heart rate is probably the
least important variable in comparing athletes," Dr. Hagerman said.
Heart
rate is an indicator of heart disease, said Dr. Michael Lauer, a cardiologist
and the director of clinical research in cardiology at the Cleveland Clinic
Foundation. But, he added, it is not the maximum that matters: it is how quickly
the heart rate falls when exercise is stopped.
An average healthy
person's heart rate drops about 20 beats in a minute and the rates of athletes "nose
dive by 50 beats in a minute," Dr.
Lauer said.
In three recent studies, Dr. Lauer and his colleagues
found that people whose rates fell less than 12 beats within a minute after
they stopped exercising vigorously had a fourfold increased risk of dying
in the next six years compared with those whose heart rates dropped by
13 or more beats.
Dr. Lauer pays no attention to the standard
formula when he gives treadmill tests. More than 40 percent of patients,
he said, can get their heart rates to more than 100 percent of their predicted
maximum. "That tells you
that that wasn't their maximum heart rate," Dr. Lauer said.
The
danger, he said, is that when doctors use that formula to decide when to
end a treadmill test, they can inadvertently mislead themselves and their
patients. Some patients may be stopping too soon and others may seem to
have a heart problem because they never can get to what is supposed to
be their maximum rate. "Some people are being pushed
and others are not," Dr. Lauer said. "In my view, that is unacceptable."
Yet,
Dr. Seals said, many doctors want some sort of guide for estimating maximum
heart rates for treadmill tests. And many people who want to increase their
fitness crave a general formula. So Dr. Seals and his colleagues decided
to take another stab at finding an equation.
In a study published
in the March issue of The Journal of the American College of Cardiology,
Dr. Seals and his colleagues devised a new formula: maximum heart rate
equals 208 minus 0.7 times age. They used published studies involving 18,712
healthy people and data from 514 healthy people they recruited. Their formula
gives much higher average maximum heart rates for older people, with the
new and old heart rate curves starting to diverge at age 40.
But
raising doubts about the heart rate formula is unlikely to lead people
to abandon it, exercise physiologists say. What would they do without it?
"I've
kind of laughed about it over the years," Dr. Haskell
said. The formula, he said, "was never supposed to be an absolute
guide to rule people's training." But, he said, "It's so typical
of Americans to take an idea and extend it beyond what it was originally
intended for."
Resting Heart Rate
Your true Resting Heart Rate (RHR) should be measured for a full minute,
right after you wake up, but before you get out of bed in the morning. Your
heart rate should be taken at your carotid or radial artery using your index
and middle fingers or with a heart rate monitor. Count your pulse while timing
yourself for one full minute. As you get fitter your heart becomes more efficient
at pumping blood around the body. As a result you will find your resting
heart rate gets lower so you will need to check your RHR on a regular basis.
Training Zones
Training zones are based
on a percentage window of your maximum heart rate. Within each training zone
subtle physiological effects take place to enhance your fitness:
The Energy Efficient or Recovery Zone - 60% to 70%
Training
within this zone develops basic endurance and aerobic capacity. Another advantage
to running in this zone is that while you are happily fat burning you may
lose weight and you will be allowing your muscles to re-energise with glycogen,
which has been expended during those faster paced work-outs.
The Aerobic Zone - 70% to 80%
Training in this zone will
develop your cardiovascular system. The body's ability to transport oxygen
to, and carbon dioxide away from, the working muscles can be developed and
improved. As you become fitter and stronger from training in this zone it
will be possible to run some of your long weekend runs at up to 75%, so getting
the benefits of some fat burning and improved aerobic capacity.
The Anaerobic Zone - 80% to 90%
Training in this zone will
develop your lactic acid system. In this zone your individual anaerobic threshold
is found; sometimes referred to as the point of deflection (POD). During
these heart rates, the amount of fat being utilised as the main source of
energy is greatly reduced and glycogen stored in the muscle is predominantly
used instead. One of the by-products of burning this glycogen is lactic acid.
There is a point at which the body can no longer remove the lactic acid from
the working muscles quickly enough. This happens at an individual heart rate
for us all and is accompanied by a rapid rise in heart rate and a slowing
of your running pace. This is your anaerobic threshold or POD. Through the
correct training it is possible to delay the POD by being able to increase
your ability to deal with the lactic acid for a longer period of time or
by pushing the POD higher.
The Red Line Zone 90% to 100%
Training in this zone will
only be possible for short periods of time. It effectively trains your fast
twitch (Type II, white, anaerobic) muscle fibres and helps to develop speed.
This zone is reserved for interval running and only the very fit are able
to train effectively within this zone.
VO2 Max & VO2 Max Testing
Firstly, your VO2 Max is the
volume of oxygen your body uses during one minute of maximal exercise. A
VO2 Max test involves a graded exercise test on a stationary exercise machine
(any exercise machine can be used). The test starts at a very easy level
and increases intensity in one minute stages until you cannot continue. Your
nose will be plugged, you will breathe through a mouthpiece connected to
a metabolic analyser, and you will wear a heart-rate monitor. The analyser
measures the volume as well as the percentage of carbon dioxide and oxygen
in the expired gas. From this data, it is possible to calculate your Aerobic
Threshold, your Anaerobic Threshold and of course, your VO2 Max.
Aerobic Threshold
Aerobic threshold is
the intensity or heart-rate at which an individual burns the most fat. Using
fat for fuel, more oxygen is required to release a given amount of energy
than when carbohydrate is the main fuel. This means that at low intensities,
when plenty of oxygen is available to the muscle, fat is the preferred fuel.
As intensity increases, at some point the cardiovascular system will not
be able to transport (proportionally) more oxygen the muscles. This is the
aerobic threshold. Above this point, increased intensity will reduce fat
burning.
Anaerobic Threshold
Also known as the Red-Line and POD
to endurance athletes, this threshold is the highest intensity, as measured
by heart rate, at which the body can remove lactic acid as quickly as it
is produced. Just below anaerobic threshold (AT), an athlete is working hard,
but feels no burning in the muscles and is breathing heavily, but controlled.
Above AT, lactic acid is building up in the muscles and will cause premature
fatigue. Knowing one's threshold allows one to achieve a very high level
of cardiovascular conditioning without the discomfort and muscle damage of
lactic acid buildup.
VO2 Max
For those who take the test to completion (so that
we are able to determine VO2 Max), VO2 Max is the volume of oxygen your body
uses during one minute of maximal exercise (as already said above). The units
of measurement are expressed as litres of oxygen per minute or millilitres
of oxygen per kilogramme of bodyweight per minute, this data tells your potential
for endurance athletics.
Basal Metabolic Rate (BMR)
Basal metabolic rate refers to the amount of energy (calories) your
body "burns" in
a resting state. There are two fairly robust scientific measures that are
used to obtain an individual's metabolic rate: Direct colorimetry and Indirect
colorimetry
Direct colorimetry involves isolating the person in a sealed chamber and measuring heat as it is released. Indirect colorimetry is less precise but easier to accomplish. It measures the total amount of oxygen a person uses and converts that measure into calories spent.
Assuming you do not have access to pressurised chambers or scientific oxygen measuring equipment there is a third method one can use; the BMR Formula. The BMR formula uses the variables of height, weight, age and gender. This is more accurate than calculating calorie needs based on body weight alone. The only factor it omits is “lean body mass” and thus the ratio of muscle-to-fat a body has. Remember, leaner bodies need more calories than less leaner ones. Therefore, this equation will be very accurate in all but the very muscular (will underestimate calorie needs) and the very fat (will over-estimate calorie needs).
BMR Formula
Women : BMR
= 655 + (9.6 x weight kg) + (1.8 x height cm) - (4.7 x age yr)
Men : BMR
= 66 + (13.7 x weight kg) + (5 x height cm) - (6.8 x age yr)
To determine the number of calories you burn up in your day to day routine, we use the Harris Benedict Equation.
Harris Benedict Equation
The Harris Benedict Equation is a formula that uses your BMR and then applies an “activity factor” to determine your total daily energy expenditure (calories). The only factor omitted by the Harris Benedict Equation is (again) lean body mass.
To determine your total daily calorie needs (C), multiply your BMR by the appropriate activity factor, as follows:
Activity Factor
sedentary (little or no exercise):
C = BMR x 1.2
lightly active (light exercise 1-3 days/wk): C = BMR x 1.375
moderately active (moderate exercise 3-5 days/wk): C = BMR x 1.55
very active (hard exercise 6-7 days/wk): C = BMR x 1.725
extra active (very hard exercise): C = BMR x 1.9
For example, If you are sedentary and have a BMR of 1745. Multiply your BMR by 1.2 = 2094. This is the total number of calories you need in order to maintain your current weight.
Once you know the number of calories needed to maintain your weight, you can easily calculate the number of calories you need to eat in order to gain or lose weight.
Below is a table showing the amount of calories burned from different activities;
Activity Total Calories/Hr
Ballroom Dancing 125-310
Canoeing (slowly) 180-200
Cooking 185-200
Walking Slowly (2-1/2 mph) 210-230
Cleaning 235-355
Brisk Walking (4 mph) 250-345
Golf 300-350
Jogging (6 mph) 315-480
Cycling (9 mph) 315-480
Tennis 315-480
Skating 320-400
Gardening (heavy) 450-525
Basketball 480-625
Aerobic Dancing 480-625
Swimming 480-625
Cross Country Skiing 480-625
Body Mass Index
Your Body Mass Index is based on your height
and weight (weight should be measured without clothing). Generally, a healthy
BMI ranges from 18.5 to 25. People with larger frames and more muscular physiques
may fall outside the guidelines without being unhealthy so don't be too put
off by your BMI!
To calculate your Body Mass Index, take your weight (in
kilograms), and divide by the square of your height (in meters). For example,
if you weigh 16 stones, which we will say is exactly 100kg and are 6ft or 1.83
meters tall, then your BMI is (100/(1.83) 2 ) = 29.86 (kg/M 2 ). This means
you are overweight. However, as said above, if you are of above average muscularity
then this value doesn't mean much! The Table below sets out the BMI for Men
and women and the categories in which they fall;
Adult Women Men
anorexia < 17.5
underweight <19.1 <20.7
in
normal range 19.1-25.8 20.7-26.4
marginally
overweight 25.8-27.3
26.4-27.8
overweight 27.3-32.3 27.8-31.1
very
overweight or obese >32.3 >31.1
severely
obese 35
- 40
morbidly obese 40
- 50
super obese 50
- 60
There is a formula one can use to calculate their lean body weight (LBW), we have listed them here for men and women:
Men
LBW =
(1.10 x Weight(kg)) - 128 ( Weight 2
/(100 x Height(m)) 2 )
Women
LBW (women) =
(1.07 x Weight(kg)) - 148 (
Weight 2 /(100 x Height(m)) 2 )