Introduction

You've probably heard the term 'cardiovascular'/'cardiorespiratory' exercise. The fitness industry uses the term broadly.

However, not all cardio is the same.

While cardiovascular training ('cardio' for short) has to do with the heart and lung function, 'aerobic' implies that it has something to do with oxygen.

Aerobic means literally: "with air."

It's therefore extremely useful to understand an important relationship between cardio and oxygen, by looking at two distinctions:

Aerobic

  • Physical activity performed in the presence of oxygen. The heart supplies increased levels of oxygen-rich blood to the lungs to enable your body to sustain the activity it's being called upon to do. Your physiology will allow you to continue, albeit with labored breathing, so long as this particular energy pathway (aerobic metabolism) can adequately meet the demands.

    Generally, low to moderate-intensity exercise or activities which are sufficiently supported by the aerobic metabolism, can be performed for extended periods of time (beyond 2 minutes).
     
  • The aerobic energy system is typical of endurance exercise and sport, where extended duration and lower intensity output is required.

Anaerobic

  • Physical activity performed without the presence of oxygen. Energy is derived from a limited supply of phosphates, adenosine triphosphate (ATP), creatine phosphate and glycolosis from the muscles, liver and red blood cells. The anaerobic pathway uses glucose and glycogen as energy in the absence of oxygen when needed at a rate which exceeds that provided by the aerobic energy pathway.

    High-intensity exercise or activities which last from mere seconds and drop off drastically at around 2 minutes. Activities lasting longer, by definition, have larger aerobic metabolic components.
     
  • The anaerobic energy system is typical of non-endurance exercise where strength, speed, power and hypertrophy are the objectives.

NOTE: The anaerobic energy pathway inherently constitutes a 'whole-body' metabolic expenditure. Fast-twitch muscle fibers (in contrast to slow-twitch muscle fibers) are fuelled by the anaerobic metabolic system, which produces maximum energy quickly, but also causes muscles to fatigue rapidly.


Aerobic vs Anaerobic functions in exercise

Differences

These different energy pathways enable either the likes of lower-intensity endurance sport on the one hand, or strength training and sprinting on the other.

The two types of exercise differ mainly by:

  1. The duration and intensity of muscular contractions involved, and:
  2. How energy is generated in the muscles.

Training effects

Cardio training involves movements which increase heart rate, and thereby improve the body's efficiency and rate of oxygen, fat or glycogen consumption. As a form of exercise, cardio is invaluable to all training protocols for anybody.

Yes, it includes people like Al, all the way up to professional athletes.

The role of 'cardio' in the Sensible Fitness Program

You probably already know that this Site's main offering is Al's best option for lifelong functional strength, fitness and overall wellbeing: the Sensible Fitness Program

In terms of cardio, the goal is to afford both an enhanced heart and lung function, as well as provide an effective fat-burning effect to facilitate steady weight loss–while bolstering hypertrophy.

Remember, there are many claims out there which promise instant results.

Don't be deceived, there is no one 'best exercise to lose weight.'

Effective and permanent weight loss comes from a responsible and committed effort which includes resistance exercise, cardio training and an appropriate eating plan.

This is the 'best way to lose weight.'

So, included in the Sensible Fitness Program are the following:

High-intensity interval training (HIIT)

  • Exercising at the higher end of the target (or training) heart rate (THR).

The idea behind HIIT (I usually use sprinting) is for the anaerobic benefits of: 1. weight loss (or control) through: excess post-exercise oxygen consumption (EPOC), sometimes referred to a the 'afterburn', 2. optimized cardiovascular fitness (particularly heart and lung function), 3. Overall physiological conditioning.

Low and moderate-intensity steady state (LISS/MISS)

  • Exercising at the lower and middle zone of the target (or training) heart rate (THR).

The goal of LISS and MISS is for the aerobic effect of: weight loss (or control) through energy consumption and fat mobilization during exercise, 2. optimized cardiovascular fitness (particularly heart and lung function), 3. Overall physiological conditioning (particularly blood circulation and capillarization).

Cardio intensities and appRopriate heart-rates

For people like Al (especially if new to cardio), it's definitely wise to know how hard to push. Technically-speaking, to measure physiological stress during physical activity.

For that, the rating of perceived exertion (RPE) is a useful means to 'gauge' the level of effort and overall discomfort while exercising. (There's an explanation and a table on the Sensible Fitness Program page.)

However, in terms of heart-rate, it's also desirable to train within a range which allows your body to obtain the maximum benefit from cardio. The so-called 'range' varies, primarily in line with age. However, other factors like physical condition, gender etc. can also be utilized in calculations.

So, to gain optimal benefits from cardio training, you need to know how fast your heart-rate needs to be.

For this you need to acquaint yourself with your own 'resting', 'maximum' and 'target' (or training) heart-rates (RHR, MHR and THR).

Two popular formulas for calculating THR are the Karvonen and the Zoladz methods.

Since the Karvonen method factors in resting heart rate, it's my preferred formula to calculate THR.

Before you go...

Cardio training isn't limited to running

Many people talk to me about boredom.

Please keep in mind that you're not limited to running. Activities like cycling, swimming or even attending aerobics classes are also perfectly acceptable options. I am by no means against these types of exercises–so long as you get the required stimulus.

Personally, I just prefer the simplicity of running (on the road or sometimes on my treadmill or stationary bike) purely because of time-efficiency.

I know I can be geared-up and on my feet within minutes, as opposed the additional time required to get organized with my bike, or to drive to the gym. I'll occasionally use my treadmill/stationary bike and listen to music or watch a documentary (a useful backup option when the weather's being unkind).

Whatever exercise type remains secondary to the effort applied and results obtained.

Don't sacrifice the benefits of cardio!


Cardiovascular Fitness is an invaluable part – not only of 'functional' or 'Health-Related Fitness' – but also of all-round wellness.