Cardiovascular Fitness

In order to create an effective programme it is necessary to have an in-depth understanding of the components of fitness related to what you want to achieve. You should consider what you want to be achieved and then how you are going to get there. It is hard to define ‘fitness’ as different people have their own perceptions of what it is to be fit, whether you wanted to be able to achieve everyday tasks without feeling fatigued or you wanted to be able to complete the marathon in a specific time. This short piece will hopefully give you a further understanding of the components of fitness involved in your particular programme and also how to utilise them effectively.

There are 5 different components of fitness;

  • Cardiovascular fitness
  • Muscular strength
  • Muscular endurance
  • Flexibility
  • Motor fitness

Cardiovascular fitness
Cardiovascular fitness is basically the ability of your cardio-pulmonary system to process oxygen. By process I mean getting the air into the body and delivering it to the working muscles. Your cardiovascular fitness can be measured by performing a simple VO2 max test which will determine the maximum amount of oxygen that can be processed in a unit of time. When following a prescribed Cardiovascular (CV) training programme, it will promote certain anatomical changes to the structure and function of your heart;

  • The left ventricular myocardium increases in strength so that it can pump more of the blood out in systole, so your stroke volume improves.
  • Your resting heart rate will decrease so that it will do less work when supplying the body with blood when carrying out every day functions.
  • In individuals who are mildly hypertensive (high blood pressure) their systolic blood pressure can reset at a lower level as arterial elasticity and smooth muscle contractility in arteries improves.
  • There is less variation in the electrical conductivity of the heart throughout repeated cardiac cycles, reducing the risk of arrhythmias (variation in heart).

There are also changes in blood chemistry that can have a positive effect on people who suffer from type 2 diabetes.

Now it is important to note that many of these changes improve at a lower level of intensity than those needed to improve VO2 max (lower levels of intensity CV exercise have better health gains).

The best way to measure an indication of improved CV endurance capacity is to assess whether there has been an increase in the anaerobic threshold, which is the intensity it is possible to work up to without any increases in lactate levels above a steady state. Once again, intensity levels lower than those needed to improve VO2 max can raise the anaerobic threshold.

It has been said that the minimum levels of exercise intensity needed to improve your VO2 max and your anaerobic threshold is 55-65% of your maximum heart rate (To work out your MHR a rough guide is 220 minus your age).

An important factor to take into account is that intensity and duration are interrelated and cumulative. Studies have shown that the extent of adaptive improvements on the body is determined by the total volume of exercise in terms of calories used each week (calories are a measure of energy expenditure). For example it has been shown that a minimum of 700 calories up to 2,000 + expended each week has proven to have positive health related adaptations on the body. For individuals who are training for a specific sporting or athletic event and need to improve their performance are expected to expend beyond the above amount. These figures are an estimate and are dependent on individual’s fitness levels.

According to research any combination of time and intensity that accumulates to the same expenditure will have the same effect, although 10 minutes seems to be a threshold minimum. This means that as long as you complete your target exercise load over the course of the day you will achieve the required goals. For example if your target for the day was a 30 minute, moderate intensity cardiovascular session you could either do this in one go, or do 3 x 10 minute sessions as they would both have the same desired effect as long as the total energy burned was the same.

The American College for Sports Medicine  recommended guidelines for maintaining Cardiovascular health are:

  • Frequency – 5-7 times per week
  • Intensity – 55-70% of MHR
  • Time – 30 minutes in a single session or cumulative
  • Type – Any that uses a large number of muscle groups.

Guidelines for Maintaining Cardiovascular fitness are:

  • Frequency – 3-5 times per week
  • Intensity – 55-90% of MHR
  • Time – 20-60 minutes
  • Type – Any continuous exercise that uses large muscle groups
  • (All above information was interpreted from CYQ 2003 exercise and fitness knowledge)

    If you are not sure that you are training effectively, to your potential or even over training, feel free to contact me with any queries and I will be happy to help.