Is it necessary to go all out during your cardiovascular workouts to reap the maximum health benefits?
My younger self would have said yes (the adrenaline rush felt good), but my current self would disagree because really, slow and steady can still win the race and make the lifelong journey with fitness more fulfilling.
Pushing too hard daily raises your risk of injury and heart stress, whereas lighter movements allow your body to heal, making it easier to stick to a regular routine.
That’s why when athletes retire, many switch to lower-intensity training to maintain fitness, reduce physical stress and support mental well-being.
When it comes to cardiovascular workouts, there are five heart rate-based intensity levels that guide your training, each offering specific benefits from fat-burning to peak performance.
Called cardio zones, they are defined by percentages of your maximum heart rate (MHR).
This is the highest number of times your heart can beat per minute during intense exercise.
MHR is easily calculated, with the traditional formula being to subtract your age from 220.
So, for example, if you’re 50 years old, your MHR would be 170 (220-50).
But there is another, more accurate Tanaka formula for the over-40 age group, which is 208 – (0.7 x age).
So, for a 50-year-old, the MHR would be 173, according to this formula.
In theory and for safety, cardiologists advise against going past your MHR during a workout.
The cardio zones you train in determine whether your body burns mostly fat, mostly carbohydrates, or a mix of both.
They comprise:
- Zone 1 (50-60% of your MHR) is the lightest effort, involving no strain, such as taking a stroll in the mall.
- Zone 2 (60-70% of your MHR) is a comfortable, sustainable pace, like a brisk walk, relaxed swimming or easy jogging where you can do the activity for longer periods without getting overly tired.
If you don’t know how to calculate your MHR, use the talk test where you should be able to have a full conversation while training.
- Zone 3 (70-80% of your MHR) is where effort is steady, moderate-to-high intensity.
You feel challenged and talking becomes choppy.
The body burns a combination of carbohydrates and fat for energy.
- Zone 4 (80-90% of your MHR) is a hard and demanding training level.
You are pushing close to your limit, and your body starts producing lactate faster than it can clear it.
High intensity interval training (HIIT) falls into this category.
- Zone 5 (90-100%) requires maximum effort such as sprinting – you’re gasping for air.
A growing body of research shows that Zone 2 cardio delivers significant health and fitness benefits.
The idea is to keep moving in a controlled manner, without focusing on speed.
This zone has become popular for building aerobic endurance because it keeps you in a range where fat is your dominant fuel source, with minimal depletion of your glycogen (stored carbohydrate) reserves.
Glycogen depletion occurs when the body’s stored carbohydrate reserves are exhausted, leading to severe fatigue, reduced performance and metabolic shift.
Most elite endurance athletes spend two-thirds of their training time in this zone, with the remaining time at high intensity.
Due to the mild effort required, Zone 2 activities can be sustained for at least 30 minutes or longer, slowly building your aerobic capacity.
For optimal cardiovascular health, the recommendation is to engage in 150 minutes of moderate-intensity aerobic activity a week – Zone 2 cardio falls into this category.
Hence, you can work up to doing an easy Zone 2 session daily to meet this target, without needing days to recover.
For beginners, this is a great way to start a fitness routine.
Revathi Murugappan is a certified fitness trainer who tries to battle gravity and continues to dance to express herself artistically and nourish her soul. For more information, email starhealth@thestar.com.my. The information contained in this column is for general educational purposes only. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
