I recently had a dear friend send me a news article and she wanted to hear my thoughts or take on the piece - which is the inspiration behind this blog post and to talk about the importance of cardiorespiratory fitness and training in regards to our health. The article was about the topic of running vs. walking and what is “better”. My simple response, would be neither, they are both great forms of exercise for different reasons - let’s dive into it.

Here is the article…

👉 Walking vs. Running: Which Is Better for Your Health? – The New York Times

I think it’s always best to start with a simple, digestible understanding of what we’re actually talking about. Once you grasp the basics, it becomes easier to recognize the health benefits—which, in turn, creates real incentive to incorporate it into your lifestyle and daily routine. So that’s where I’ll begin. But first: why all the hype, and what are the actual health benefits?

Cardiorespiratory fitness is widely recognized as a key indicator of overall health. It’s strongly associated with a reduced risk of chronic disease and lower mortality rates. At its core, it reflects the strength and efficiency of your heart and lungs, and your body’s ability to deliver oxygen to working muscles during physical activity. When cardiorespiratory fitness is high, the benefits are significant: a lower risk of cardiovascular disease, type 2 diabetes, certain cancers, and even improved mental health.

“In the Aerobics Center Longitudinal Study (ACLS), compared with the least fit men and women, the most fit men and women had 43% and 53% lower risk for all-cause mortality, and 47% and 70% lower risk of CVD mortality, respectively.”
- PubMed Central

What is cardiorespiratory training and how does it work?

Cardiorespiratory training involves two closely connected systems: the cardiovascular system and the respiratory system.

🫀 Cardiovascular System

Includes the heart, blood, and blood vessels.
Its primary role is to transport blood throughout the body, delivering oxygen and nutrients to tissues while removing waste products.

🌬️ Respiratory System

Includes the trachea, lungs, bronchi, and alveoli.
Its main function is to facilitate the transportation and exchange of oxygen and carbon dioxide between the body and the external environment.

“These systems work together to provide the body with adequate oxygen, nutrients, protective agents, and a means to remove waste products from the body.”
— National Academy of Sports Medicine

VASCULAR (or circulatory) SYSTEM

The vascular system is responsible for transporting blood from the heart to the tissues throughout the body. At the center of this system is the heart—a muscular pump that rhythmically contracts to circulate blood. The heart is a cardiac muscle, meaning it functions involuntarily (we can’t consciously control it), yet it can be strengthened through consistent cardiorespiratory training. Think of the heart as a MUSCLE you put the reps in to strengthen.

💡 Key Performance Metrics

Heart Rate + Stroke Volume = Overall Heart Performance
Cardiac Output = Heart Rate × Stroke Volume

Heart rate refers to how fast your heart is beating—measured in beats per minute (bpm). In the fitness world, it’s a useful indicator of how hard your heart is working during exercise and helps gauge intensity levels.

Stroke volume is the amount of blood pumped out of the heart with each beat. Together with heart rate, it determines your cardiac output, which reflects how efficiently your heart is delivering oxygen-rich blood to your body.

Blood pressure, on the other hand, measures the force of blood pushing against the walls of your arteries as the heart pumps. It’s a common metric in medical settings and a key safety consideration in fitness—often used to determine whether someone is cleared for safe physical activity.

🩸 The Many Benefits of Blood

I came across this information in the National Academy of Sport Medicine textbook, found this SO FASCINATING and thought to myself blood is like the miracle juice of the human body!

Just take a look at all the incredible roles blood plays in the human body—and it quickly becomes clear why you’d want this magic juice pumping through your system at a more vigorous rate on the daily. It’s extremely valuable.

“Blood acts as a medium to deliver and collect essential products to and from the tissues of the body, providing an internal transportation, regulation, and protection system.”
— National Academy of Sports Medicine

Let’s break it down:

🚚 Transportation

Blood serves as the body’s internal delivery system:

Transports oxygen and nutrients to tissues
Removes waste products from tissues
Delivers hormones to organs and tissues
Carries heat throughout the body

🌡️ Regulation

Blood helps maintain internal balance:

Regulates body temperature
Maintains acid-base (pH) balance

🛡️ Protection

Blood defends and preserves the body:

Prevents excessive bleeding through clotting
Contains immune cells that fight off disease and infection

RESPIRATORY SYSTEM

The respiratory system deals with the transportation of oxygen and carbon dioxide inside and outside of the body. The function of this system is to bring oxygen into the lungs and remove carbon dioxide from the lungs to the outside air. The respiratory system includes the airways, lungs and the respiratory muscles.

“The primary role of the respiratory system is to ensure proper cellular function.”
– National Academy of Sports Medicine

The respiratory system works intimately with the cardiovascular system to accomplish optimal cellular function by…

bringing oxygen in from the environment and transferring it to the bloodstream
taking carbon dioxide from the blood to the lungs and eventually transporting it back out to the environment

It brings in what it needs through the process of inhalation and excretes what it doesn’t through exhalation.

This entire process is accomplished through the integrated functioning of the respiratory pump to move air in and out of the body and of the respiratory passageways to channel the air.

When you think about it simply, exercise that elevates your heart rate and gets your blood pumping acts like a full-body cleaning system—keeping everything moving efficiently. So keep those key blood functions in mind: it delivers and collects essential products throughout your tissues. Cardiorespiratory training supports this vital transportation, regulation, and protection.

Walking vs. Running

Now that you’ve got a basic understanding of what we’re talking about—and how training adds real value—let’s talk walking vs. running.

Both are great forms of exercise, but it all depends on the individual. The goal and intention behind the workout matter just as much.

Relative to You

Whether you walk or run should come down to your fitness level, experience, and ability to manage risk. Use heart rate and breathing to gauge intensity. A beginner might get plenty of challenge from a brisk walk, while someone more conditioned may need to run to feel that same push. The body adapts—what’s hard today gets easier with consistency.

Purpose & Intention

Ask yourself: is this about pushing your heart and lungs, or is it a recovery day? The two look very different.

If it’s a workout, find a heart rate zone that challenges you. That’s how growth happens—stress, adapt, repeat. But if it’s about movement and recovery, keep it light. Movement without strain can be just as valuable.

If your goal is to run eventually, brisk walking builds the foundation until it’s no longer enough—and then you level up.

Above all, you need a solid gait (walking mechanics) and a strong, functional body with sound biomechanics before even thinking about running.

“You need a solid gait, a strong, functional body with sound biomechanics before running.”

Where do I start?

Let your heart rate and breathing rate guide you. This is where a heart rate monitor can come in handy but if you do not have one, don’t worry about it, the talk test works well too.

You would almost always start with walking and gradually build up to running (example = walk, brisk walk, run).

Let’s talk purpose and intention first.

Purpose & Intention = movement and recovery (a walk is perfect!)

Purpose & Intention = exercise and training (a brisk walk, run, HIIT (high intensity interval training) or SIT (sprint interval training) will do the trick)

Relative to you.

For the purpose of creating a workout, we would want to challenge the heart rate and lungs - that will be relative to the individual. You can use your fitness level, experience, and ability to manage your breathing rate and heart rate to find a suitable starting point.

Generally speaking this is what it could look like to start, assuming you have been cleared for safe exercise (NO health risk factors), have a strong, functional body with good biomechanics.

New to Exercise.

Fitness level = beginner
Exercise experience = minimal - none
Intensity & duration = low intensity for a longer duration
Breathing rate (talk test) = should be able to talk during exercise
Heart rate = low to moderate intensity (zone 1-3, 50-70% of heart rate max)
Form of exercise = This would likely be a walk, brisk walk or light jog that you would build up to 30 minutes of steady state. Build up bring about to walk (or brisk walk) for 30 minutes with a manageable heart rate/breathing rate. When comfortable, do the same gradual build with jogging.

Moderate level of exercise experience.

Fitness level = intermediate
Exercise experience = moderate level, been exercising over the years (maybe off and on), but have been consistently training for the past 6 months
Intensity & duration = low to moderate intensity for moderate duration
Breathing rate (talk test) = could still talk during exercise but would prefer not to
Heart rate = moderate-high intensity (zone 2-3, 60-80% of heart rate max)
Form of exercise = This would likely be a light jog or jogging for 20-60 minutes of steady state or some HIIT.

High level of exercise experience.

Fitness level = advance
Exercise experience = exercising for years consistently, have a strong foundation and really want to spice things up
Intensity & duration = low-high intensity for short duration
Breathing rate (talk test) = talking is not possible, work intensity is too high
Heart rate = moderate-high intensity (zone 1-5, 50-95% of heart rate max)
Form of exercise = This would likely be HIIT (high intensity interval training) or SIT (sprint interval training) where you are switching between work to rest periods.

It’s important to monitor your breathing rate and heart rate to ensure the challenge is appropriate and safe. Doing so is also very critical to training effectively and knowing when it’s time to progress to the next challenge.

How do I progress safely?

Progression in fitness is not solely about increasing intensity; it’s about moving more intelligently. A structured system of stages and levels ensures safe, sustainable improvement while respecting each individual's starting point. Below is a sample framework for cardiovascular progression using heart rate zones as a guide, along with instructions on how to calculate your own heart rate training zones.

🟢 Beginner (Level 1): Build the Foundation

Goal: Establish cardiovascular endurance using a target heart rate of 50–70% of your maximum (HRmax).

This stage focuses on gradually increasing your ability to sustain movement. The aim is to work up to 30 minutes of continuous, steady-state exercise in heart rate zones 1–3. Think of this as laying the groundwork — slow, steady, and consistent.

🟡 Intermediate (Level 2): Introduce Intensity

Goal: Enhance cardiorespiratory capacity with a target heart rate of 65–85% of HRmax.

Designed for individuals with a low-to-moderate fitness base, this phase introduces interval training. Workload (speed, incline, intensity) begins to vary, helping the heart rate move in and out of zones 1–3. This variability builds resilience and prepares the body for strength-based training styles.

Focus: Learn to manipulate intensity through structured intervals — alternating effort and recovery to challenge your system in new ways.

🔴 Advanced (Level 3): Power and Performance

Goal: Maximize energy system capacity using heart rate zones 2–5.

This stage is for experienced individuals with a solid cardiovascular foundation. Training includes high-intensity intervals that alternate between low and high heart rate zones, often pushing into zone 5. This level supports power-based workouts and advanced conditioning.

Focus: Increase workload strategically to stimulate energy systems and elevate performance. High-Intensity Interval Training (HIIT) is a prime example of this phase.

Calculate your heart rate training zone and create your workout.

Calculating Your Maximum Heart Rate

Maximum Heart Rate (HR max):
HR max = 220 − age

Example:
For a 35-year-old female:
220 − 35 = 185 bpm

Determining Your Target Heart Rate Using the Heart Rate Reserve Method (Karvonen Formula)

This method takes into account your resting heart rate for a more personalized target intensity.

Formula:
Target Heart Rate = [(HR max − HR rest) × Desired Intensity] + HR rest

Where:

HR max = Maximum heart rate (bpm)
HR rest = Resting heart rate (bpm)
Desired Intensity = Target intensity expressed as a decimal (e.g., 50% = 0.50)

Example:
Given:

HR max = 185 bpm
HR rest = 60 bpm
Desired Intensity = 50% (0.50)

Calculation:
[(185 − 60) × 0.50] + 60
= (125 × 0.50) + 60
= 62.5 + 60
= 122.5 bpm

Result:
Your Zone 1 target heart rate is approximately 122.5 bpm.

Step-by-Step Process for Designing Your Workout

Step 1
Assess your current fitness level—beginner, intermediate, or advanced—based on your exercise experience and health history.

Step 2
Use the sample workout sections as a reference to help you create a personalised exercise routine tailored to your fitness level.

Step 3
Calculate your target heart rate zone using the method provided. This will give you a specific, individualised target to aim for during your workouts.

Step 4
Put your plan into action using the information you have gathered. If you’re new to exercise, start slowly and build gradually. Listen closely to your body, monitor your heart rate and breathing, and begin with what feels manageable and comfortable. As you become stronger and more conditioned, gradually increase the intensity and duration of your workouts. Think of it like progressing through school—no one expects a child to tackle complex subjects before mastering the basics.

Patience and consistency are key to long-term success.

Cardiorespiratory training is a powerful tool for building endurance, improving heart health, and supporting overall wellness. By understanding the systems involved, choosing the right starting point, and progressing safely, you can tailor your approach to meet your unique needs. Whether you prefer walking or running, calculating your target heart rate zones empowers you to train with intention and clarity.

I hope this guide helps you take the next step with confidence—I'm always here to serve, so please reach out if you need any further support.

Cardiorespiratory Fitness, Training & Health