Training for endurance is simple in theory. Putting it into practice is where things get, well, boring. Most people just hop on a treadmill or bike and just go without any long-term planning. Creativity is what’s needed to add distance and volume in your program.
Let’s dive right in to some basic physiology. I’ll try to make this sound with as much sense as possible. Most endurance athletes have heard of the term VO2 max, which is a measure of the most amount of oxygen your body can use for an amount of time. There are three factors to consider with maximal oxygen uptake (VO2 max):
- Heart rate
- Stroke volume
- Oxygen in veins versus oxygen in arteries
The first part is easy since everyone knows what heart rate is. As exercise intensity increases, so does heart rate. The confusing parts about heart rate are the 220 minus age formula and what heart rate limits to use. First, the 220 minus age formula only fits about 30 percent of the population and has about a 12 beat variation. So, for a 40 year old person their assumed maximal heart rate would be 180 beats per minute. However, one person could have a max of 168 beats while someone else could be at 192 beats.
Second, the solution is to use a heart rate monitor and set your own personal high and low heart rate limits without resorting to formulas. With my clients I have them perform a ramp test and when they hit an intensity where they get a little out of breath I know not to go beyond that point. That’s their upper heart rate limit. I then measure their one and two minute recovery heart rate. Well conditioned clients will have a one minute recovery between 25 and 40 beats. As a personal example, my upper limit is 170 beats and I get a full recovery at 130 beats, my lower limit.
The second part of the equation deals with stroke volume. All stroke volume tells us is how much blood pumps out of the heart for every beat. Obviously with more blood leaving the heart per beat, the more oxygen being supplied to muscle, hence improving endurance. There are two things to consider here. One, the more your heart can fill with blood, and two, the stronger your heart muscle can contract will pump out more blood during exercise. The first variable improves with aerobic exercise while the second improves with strength training.
The last part has to do with how well your muscles can pull oxygen out of your arteries and use it to break down fuel for exercise. Consistent aerobic exercise will develop more capillaries around muscles which allow for more oxygen to enter muscles, leaving less in veins.
All three factors can be improved with aerobic exercise, but I feel that incorporating strength training in your program can help as well. For instance, using alternating sets and circuits in strength training with minimal rest in between will elevate heart rate between your set limits. Not only are you working on your cardiovascular endurance, but also the endurance of your muscles. In part two, I will focus on practical examples involving the three factors mentioned above.
