CARDIORESPIRATORY FITNESS

Cardiovascular fitness is the most important aspect of any fitness program. Cardiovascular fitness should be the mainstay of any fitness program. This section is designed to explain the definition of cardiovascular fitness, the benefits of cardiovascular fitness program, warm up and cool down aspects of cardiovascular fitness, the different modes of cardiovascular fitness, the criteria of cardiovascular fitness, explain how to monitor cardiovascular intensity levels, the factors of improving cardiovascular fitness, and the methods of cardiovascular training.
Cardiorespiratory Fitness: A Definition

Cardiovascular fitness also called cardiorespitory fitness is the ability of the lungs to provide oxygen to the blood and the heart to transport the oxygenated blood to the cells of the body. It is also the ability of the body to sustain an activity for an extended period of time.

Benefits of a Cardiorespiratory Fitness Program

Participating in a cardiovascular conditioning program can help the participant to:

- lower blood pressure
- increase HDL cholesterol
- decrease total cholesterol
- decrease body fat due to utilizing fat as energy
- increase heart function and its ability to pump more blood
- decrease stress reactions and anxiety
- reduce glucose-stimulated insulin
- increase oxygen output to body
- decrease resting heart rate
- increase cardiac output
- increase aerobic work capacity

Now that we know the benefits of a cardiovascular program lets examine the components of a proper program.

Warm up

The warm-up should increase the heart rate, blood pressure, oxygen consumption, dilate the blood vessels, increase elasticity of the active muscles, and increase the heat produced by the muscle groups to be used during exercise.

A proper warm-up consists of two phases:

1) A graduated aerobic warm-up activity - This is a warm-up to get the blood flowing into the muscles. This also heats up the muscles making them less prone to injury. Any aerobic activity done at very low intensity can serve to warm-up the muscles, tendons, and ligaments.

2) Stretching or Flexibility - This is to be performed on the muscle groups you will be exercising during your cardiovascular activity. An example would be a quadriceps stretch before bicycling.

The warm-up phase should last anywhere from 5 - 10 minutes. For most activities 5 minutes may be good enough.

Stretching should always follow the low intensity aerobic warm-up activity as it is easier to stretch the muscle groups when they are warm. An example of a good warm-up would be 5 minutes of walking followed by 3 minutes of light stretching. Try to hold your stretch for at least 20 seconds during the warm-up

Cool Down

The purpose of a cool down is to slowly decrease the cardiovascular work and overall metabolism that were elevated during the cardiovascular activity. A cool down consists of slowing down the intensity level of the cardiovascular activity you are performing slowly. Stopping exercise suddenly can be dangerous. A cool down keeps the body circulating blood and keeps blood from pooling in the veins. A proper cool down should last about 5 -10 minutes for each thirty minutes of exercise. If the cardiovascular activity is performed for longer periods or is of higher intensity the cool down phase should last longer.

Criteria for Cardiorespiratory Exercise

For criteria we will get acquainted with the word FIT.

Frequency
Intensity
Time
Frequency - This refers to the number of times per week you perform cardiovascular exercise. To improve cardiovascular fitness levels a minimum of three days a week is recommended. The American Council of Exercise Guidelines recommend 3 -5 days per week. Remember that a person should not try to overdo it to soon but progress slowly and efficiently.

Intensity - Intensity level is a very important part of any exercise program. Exercising at correct levels can make a big difference in the effectiveness of a program. Intensity can be defined as speed or workload of an activity. Many people, such as walkers, do not exercise at the correct intensity level for cardiovascular and fat burning enhancement. On the other hand some people can actually exercise at too high an intensity level. Exercising at a high intensity level can increase a persons chance of injury. There are also people who may not get maximum fat burning potential and cardiovascular improvement because they do not keep their intensity level sustained for a long enough period of time.

A person who is beginning a program should start at 50 - 60% of their maximum oxygen consumption although some beginners need to start at levels of 40 - 50%. For fitter people exercising at 75 - 85% is probably more appropriate. Overall for healthier adults it is good to be at 60 - 70%. The key to all of this is knowing where he/she is at as far in their cardiovascular fitness level is concerned and starting slowly, progressing as cardiovascular fitness levels increase. Starting a program too fast is not good, but not doing enough is not good either. A comfortable balance which progresses to higher levels over time is recommended.

Time - This refers to the duration of an exercise session or the length of time to complete an exercise. For many the duration of an exercise depends upon the intensity of an exercise. In general the cardiovascular exercise should last a minimum of 20 minutes with the best results coming after a longer period of time. A person can get good cardiovascular fitness and body fat burning utilization at 20 - 30 minutes of cardiovascular exercise. People who are just beginning a program should start slowly and progress over time.

Monitoring Intensity

Percentage of Maximal Heart Rate

This method is the most popular used formula today. This formula can have a variability of + or - 10 to 12 beats per minutes (Dursitne, 1988). This method is measured as follows.

Target Heart Rate Range = Maximal predicted heart rate x % of intensity range x 1.15.

For Example:

A 50 year old man for whom a 60% to 70% maximal heart rate is desired:
220 - 50 = 170 x .60 = 102 x 1.15 = 117.3 (60% lower limit exercise rate)
220 - 50 = 170 x .70 = 119 x 1.15 = 136.9 (70% higher limit exercise rate)
This person would exercise at between 117 - 136 bpm.

What should my target heart rate training zone be?

This all depends on your fitness goals. Below you will find different training zones that are recommended.

1.  Healthy Heart Zone

  1. For people who are just starting an exercise program or have low functional capacity
  2. Target heart rate should be 50% - 60% of your maximum heart rate
  3. Decreases body fat, blood pressure and cholesterol

2.  Fitness Zone (fat burning)

  1. For people who want to train their muscles to burn fat
  2. Benefits are the same as the “healthy zone” with increase in total number of calories burned and provides a little more cardiovascular benefits
  3. Target heart rate should be 60% - 70% of maximum heart rate

3.  Aerobic Zone

  1. Preferred zone if you are training for an endurance event
  2. Cardiovascular and respiratory systems will improve and you will increase the size and strength of your heart; total number of calories burned increases
  3. Target heart rate should be 70% - 80% of maximum heart rate

4.  Anaerobic Zone / Red-Line Zone

  1. Improves cardio – respiratory system and burns the most number of overall calories but least percentage of fat calories
  2. Very intense; should be cleared by a physician to train in this zone
  3. Target heart rate should be 80% - 100% of maximum heart rate