Improving Cardio Endurance – the Basics
What is Cardiovascular Endurance?
Simply put, it is the ability of your heart, lungs and circulatory system to deliver oxygenated blood to throughout the body. The more efficient your cardio system, the lower your heart and breathing rates will be; both at rest and during exertive activity.
Good news for all of us! Cardio endurance can be improved with a regular aerobic exercise program. To understand the nature of the correct exercise program, we first have to establish three key criteria. They are:
1. Resting Heart Rate (RHR)
A person’s resting heart rate is simply the number of times the heart beats over a given period of time (usually one minute) while at rest. It is easy to estimate. Simply locate your pulse (either wrist or neck) and count the number of beats in 60 seconds. To speed the process up, you can reduce the number of seconds to 20 and multiply by 3, or to 15 and multiply by 4 etc. For a more accurate estimate, it is best to record your RHR a few times over the course of a day or two and calculate the average.
The typical RHR range for an adult is between 60 and 80 beats per minute (bpm). If you discover your resting heart rate is over 80 bpm, you should consult a physician before beginning an aerobic exercise program. Generally speaking, a healthy goal for RHR in an otherwise healthy person is around 65 bpm.
2. Maximum Heart Rate (MHR)
Maximum Heart Rate (MHR) is a sometimes maligned and often misunderstood concept. The most basic definition of MHR is: “the highest heat rate an individual can achieve without severe problems through exercise stress”. This definition, without context, is very scary indeed. However, for an otherwise healthy subject, the MHR is more representative of the maximum heart rate the subject can achieve through exertive exercise. If simply reaching MHR resulted in a catastrophic cardiovascular event, elite athletes everywhere would be dropping like flies.
The calculation of MHR is often debated. There is a simple formula, and others which are more complicated.
Basic MHR Formula: 220* – age = MHR
Using the Basic Formula, a 45 year old healthy adult has an estimated MHR of 175 bpm
*It is often suggested that women should use 226 as the minuend.
Advanced MHR Formula: 206.9 – (0.67 x age) = MHR
This Advanced Formula (and others like it) has proven to be more accurate for calculating MHR for older subjects. The Basic Formula tends to underestimate MHR for people over 60 years of age.
Using the Advanced formula, a 45 year old healthy adult has an estimated MHR of 176.75 bpm.
3. Target Heart Rate (THR)
Target Heart Rate (THR) is the optimal range for a subject’s heart rate (in bpm) to achieve improvement in cardiovascular performance through aerobic exertion. As the previous statement suggests, THR is not a fixed result; but rather, a range. The THR range is derived from a subject’s MHR estimate. Like many of the other factors pertaining to heart rate calculations, the specifics of the recommended THR range is not universally agreed upon; however, the broadest range is between 50% and 90% of the MHR. Although, many trusted sources would recommend a more narrow range of 60% to 85%.
Using the 60/85 rule, the 45 year old subject contemplated in section #2 would have a THR range of between 105 bpm and 149 bpm.
0.60 x 175 MHR = 105 bpm……and 0.85 x 175 MHR = 149 bpm
If the subject followed the recommended aerobic exercise regime (see below), at a level of sustained exertion that maintained their heart rate within their THR range, they would be positively affecting their cardio endurance. If they failed to maintain their exertion above the minimum threshold of the THR, the cardio endurance benefit would be negligible. If they exceeded the THR range, the exertion level would enter the realm of anaerobic. Although there are other fitness benefits to anaerobic exercise, it would not benefit cardio endurance.
Beginners’ Guidelines for Cardio Endurance Performance
If you are only just beginning to approach the goal of improving cardio endurance performance, the basic recommended program is as follows:
30 minutes of sustained aerobic exercise (within your THR range) 5 days per week
If you are truly a beginner, it is best to start with exercise that elevates the heart rate into the lower THR range. Once you become more comfortable with the sensation of an elevated heart rate, you can push the level of exertion further up the range.
Once you have established a routine, and feel confident in your abilities, you can elevate your workouts to the intermediate and advanced level for cardiovascular endurance training – exploring concepts such as Aerobic Training Zone (to be expanded upon in an upcoming blog post).
For expert advice on building a cardio endurance program, talk to a member of our expert fitness staff.
*It is always recommended that you consult your physician before commencing a new exercise program. The estimation of RHR, MHR and THR do not apply to those with existing cardio vascular disease or other medical conditions.