Zone 2 cardio puts the “steady” in “steady-state cardio.” It’s not as flashy as high-intensity interval training (HIIT) or dramatic as bonkingyet it deserves just as much attention.
Zone 2 cardio is fundamental to any fitness routine, whether you are an endurance athlete who wants to improve their performance or someone who just wants to be healthy, functional human.
So, if you’ve noticed a “trend” around this type of exercise, know this: Low Intensity Steady Cardio (LESS cardio) has always been around. And if, until now, it hasn’t been part of your exercise routine, it’s time to change.
What is Zone 2 Cardio?
Zone 2 cardio refers to a specific exercise intensity that you can sustain for an extended period, during which your heart rate is about 60 to 70 percent of your body. maximum heart rate. (Your max heart rate is the number of times your heart beats in one minute during an all-out effort, such as sprinting the final stretch of a 5K. More on how to determine your max heart rate later.) In this area, you may be short of breath, but you are not gasping for air.
There are five heart rate zoneseach of which has a target range based on a percentage of your maximum heart rate (MHR). Below is a general breakdown of heart rate zonesbut note that these numbers are estimates and may differ depending on your source and from one person to another.
| Area | Intensity | % of MHR |
|---|---|---|
| Zone 1 | Low-moderate | 50% – 60% |
| Zone 2 | moderate | 60% – 70% |
| Zone 3 | Moderate-high | 70% – 80% |
| Zone 4 | High | 80% – 90% |
| Zone 5 | Very high | 90% – 100% |
Zone 2 Cardio Benefits
Like any form of cardio exercise, zone 2 cardio can enhance heart health and reduce the risk of cardiovascular disease. And because it burns calories, steady-state cardio is an effective tool for weight loss and healthy weight management. Zone 2 cardio (and movement, in general) can also positively it affects your mood and mental health and improve the quality of your sleep.
But cardio that specifically keeping your heart in the zone 2 zone also offers some unique benefits, especially for endurance athletes who want to improve their performance. Here are a few:
1. More mitochondria
If it’s been a while since you’ve taken a biology class, here’s a quick refresher on what mitochondria are and why they’re critical to athletic performance:
Mitochondria are a type of organ found in body cells that use oxygen to produce adenosine triphosphate (ATP), the primary source of energy that fuels physical activity and basic biological functions. More mitochondria means more ATP and therefore more energy for physical activity.
Todd Buckingham, Ph.D. Exercise Physiologist at PTSportsPRO in Grand Rapids, Michigan, explains that zone 2 cardio is “ideal for mitochondrial development.” Working at a sustainable intensity for a longer duration increases the demand on your cells for energy, and the body adapts to this demand by producing more mitochondria.
So, for athletes who want to increase their endurance (or just feel better during and after a workout), zone 2 cardio is essential.
2. Capillary development
Capillaries are small blood vessels that deliver oxygen-rich blood to muscle cells, where the oxygen is used to make energy by the mitochondria. According to Buckingham, optimal capillary development occurs in zone 2, between 60 and 70 percent of your maximum heart rate.
A more robust network of capillaries allows your body to put more oxygen available for good use during exercise.
3. Longevity
Even if you’re not trying to set any new PRs, zone 2 cardio can improve your daily life simply by extending it. “Exercise of zone 1 and zone 2 has been shown to increase life expectancy“says Buckingham. “It helps increase your VO2 maxand there is a direct relationship between your VO2 max and your longevity.”
VO2 max is a cardiorespiratory fitness metric that scores how efficiently your body uses oxygen. (The link between VO2 Max and zone 2 cardio makes sense, considering what we know about capillaries and mitochondria.) The number measures milliliters of oxygen per kilogram of body weight per minute (ml/kg/min).
4. Requires less recovery
HIIT it’s popular for many reasons: it’s fast, efficient, fun (depending on who you talk to), and offers many of its own unique benefits. That said, high-intensity exercise is demanding more recovery than the exercise of low or moderate intensity, and do too much of this can also have a negative impact on your health.
Because it is less intense, zone 2 cardio requires less recovery time, which makes it easier to be consistent with your fitness routine and stay active between workouts. (If you’ve ever been too sore to function after a HIIT session, you have.)
Additionally, steady-state cardio is generally accessible to more people, including those new to fitness, individuals with injuries or mobility issues, and older adults.
When not using Zone 2 Cardio
While almost everyone, from a health perspective, will benefit from incorporating LISS into their workout routine, focusing on zone 2 cardio will not help you achieve certain performance goals.
If you are worried develop explosives and power – maybe you’re a sprinter, a high jumper, or a baseball player – zone 2 cardio shouldn’t be your primary focus. Instead, you have to prioritize brief bouts of intense movement.
How often and how long do you need to train in Zone 2?
Along with two days of muscle-strengthening exercise, the Centers for Disease Control recommends the following weekly guidelines for aerobic activity:
- 150 minutes of moderate intensity activity (aka zone 2 cardio)
- 75 minutes of vigorous intensity activity
- An equivalent combination of moderate and vigorous intensity activities
However, your training should be aligned with your goals, fitness leveland lifestyle. For example, an avid runner training for a marathon needs to log more zone 2 cardio per week than a parent pressed for time who has just started exercising for the first time.
That time can be distributed throughout the week (for example, five 30-minute workouts) and also throughout the day with exercise “snacks”. For example, you can do a 15-minute jog in the morning and a 15-minute bike ride after dinner for a total of 30 minutes.
If 150 minutes a week feels like an excessive amount of steady-state cardio, do what you can, says Buckingham.
“If you only have time for 10 or 15 minutes, it’s still better than nothing. People make the mistake of going, ‘I only have time for 10 minutes of exercise, so it’s not even worth it,'” he says. 10 minutes five days a week will be better than zero minutes five days a week.”
How to know when you are in Zone 2
You can use a wearable heart rate monitor to track your heart rate. But to know when you are in zone 2, you must first determine your maximum heart rate. If you don’t have access to a lab or testing facility (and most of us don’t), you can use this formula to generate a rough estimate:
220 – (current age) = maximum heart rate
Therefore, the average 30-year-old person should have a maximum heart rate of 190, and their zone 2 heart rate should be between 114 and 133 bpm.
However, this equation has been reported to judge the maximum heart rate from 10 to 12 bpm. It has also been found to overestimate and underestimate maximum heart rate in younger and older adults, respectively.
So, Buckingham recommends doing your own testing on a treadmill or outside. “Run as hard as you can for 10 to 15 minutes, maxing out at the end,” he says. When you are at your peak level of effortnote your heart rate and use this number to calculate your zone 2 heart rate.
Alternatively, you can use the “speech test” to keep you in zone 2. “When you do the exercise, you should be able to hold a full conversation, speaking in complete sentences without being out of breath,” says Buckingham. “If you’re gasping for air, you need to slow down.” You should be moving at a pace and intensity that feels moderately challenging but sustainable.
Examples of Cardio Zone 2
Almost any form of exercise can be considered zone 2 cardio if you keep your heart rate in the appropriate range for the duration of your workout. Here are some common examples:
- Quick walk
- Jogging
- Race
- Excursionism
- Swimming
- Dancing
- Aerobics
- Cycling
- rowing
- Elliptical formation
