HOW TO IMPROVE YOUR CONDITIONING - PART 1.

Doing a deep dive on Endurance Training, you quickly find that there are many different systems, classifications and styles of conditioning.

You run into terms like VO2max, Anaerobic Threshold, O2 saturation, fatigue index, M.A.S. etc.

It sounds complicated.

With all of this running through your head, you may ask yourself, "Where do I get started?"

The answer is simple:

The Cardiac Output Method (or plain vanilla low-intensity aerobic activity).

20-90min sessions of some kind of high turnover/low impact/cyclical activity. 
Your heart rate should stay somewhere between 130-150bpm.  
Running, swimming, rowing, riding, or skipping are movements that work well.
This method lends itself well to circuits (Row, then Bike, then Run, repeat), and you can measure progress by increasing pace/power/distance at similar heart rates.

Because it's only a bit faster than a conversational pace, the Cardiac Output method often gets tossed aside because it doesn't "feel" overly challenging. 

This is too bad because Cardiac Output is the way to go to build a solid aerobic base.  

It does this by causing an adaptation in the heart to increase its left ventricle's internal diameter and allows it to pump a higher volume of blood with each stroke. 

This results in a lower resting heart rate, lower working heart rates, lowered blood pressure, and it helps increase work capacity.

There are a lot of wins there.

Suppose your resting heart rate is above 60 beats per minute. In that case, the general recommendation is 1-3 Cardiac Output sessions a week to widen your aerobic base.

If your resting heart rate is below 60 beats per minute, Cardiac Output work still has value; however, your sessions can be less frequent, and you can start to layer in higher output conditioning methods into your routine.