How to Build Endurance for a Stronger Heart and Muscles

When faced with low energy levels hindering daily activities or even a new hour-long fitness class, it's easy to attribute it to a poor night's sleep or common stressors. However, amidst these factors, it's important to recognize the impact of your physical endurance.

What Is Endurance?

Physical endurance refers most simply to one’s ability to maintain a certain level of activity for a prolonged amount of time. Endurance is a term we often hear associated with athletes, especially those who compete in a sport that requires them to go the distance and withstand tiring feats of muscular and cardiovascular over extended stretches of time (think: marathon runners, professional soccer players, cross-country skiers). But elite athletes aren’t the only ones who benefit from—or need—physical endurance. Whether you want to enjoy a long walk with your dog or spend the day at an amusement park with your kids, every single body requires some level of endurance to power through life. And it’s something you can improve and build upon anytime.

There are two types of physical endurance, cardiovascular endurance and muscular endurance.


Cardiovascular Endurance

“Cardiovascular endurance is your body’s capacity to exercise for an extended period, such as running a 5K or taking a spin class,” says Jen Rulon, fitness coach and 15-time Ironman triathlete. This type of endurance is what you need to sustain activity any time you get your heart pumping, when your heart and lungs are working together to help fuel your body with oxygen.

“Cardiovascular endurance is critical for your daily life and performance in sports and physical activity,” says Alex Rothstein, MS, CSCS, coordinator and instructor for the exercise science program at New York Institute of Technology in Long Island. 

So how do you build endurance? As you might guess, movement—aerobic activity—is key for several reasons. The more endurance you have, the more “[y]ou’ll be able to perform an activity at greater intensities and for longer durations,” Rothstein says. If you’ve ever gotten fatigued during an activity, or even stopped an activity because you feel a burning sensation, those two incidents will be reduced if you improve your cardiovascular endurance.  

Increasing your cardiovascular endurance can lead to significant improvements in your overall health. Better endurance can help lower your cholesterol and blood pressure, Rulon says, as well as boost your respiratory and circulatory systems. 

Endurance vs. Stamina

Note, though, that endurance is often confused with stamina. While the two are similar and related, cardiovascular endurance focuses on just the physiological components of maintaining physical effort, whereas stamina includes the psychological as well as the physiological components. “Stamina is a combination of cardiovascular endurance and the perception of fatigue,” Rothstein says, adding that it also includes the ability to push past the feeling of fatigue.

Muscular Endurance

Cardiovascular endurance primarily involves your heart, but muscular endurance is related to the strength and ability of your muscles. “It’s how often you can move a weight without getting tired, something you need to improve your cardiovascular system,” Rulon says.

You can’t talk about muscular endurance without mentioning muscular strength, or the maximum amount of force that can be produced one single time. With better muscular strength and endurance, “you’ll become better at handling stress or cardiovascular training,” Rothstein says.

How to Build Endurance

If you want to build these two types of physical endurance, it’s time to get moving. Building cardiovascular endurance requires doing cardiovascular or aerobic activity (like walking, jogging, swimming, or cycling), but how you do that activity matters, which is where a principle called “specific adaptation to imposed demands'' (SAID) comes into play. The SAID principle states that the body will adapt to the specific demands imposed upon it. “To become better at cardiovascular endurance, your cardiovascular system needs to be challenged with enough stress to signal a need to adapt,” Rothstein says.

To do this, there are three main variables you can play with: 

·        Frequency (how often you exercise) 

·        Intensity (how hard you exercise) 

·        Duration (for how long you exercise) 

“Increasing and/or decreasing any one or combination of these variables will challenge your cardiovascular system differently and cause different adaptations to occur,” Rothstein explains. For instance, increasing the duration of your workouts will tell your body to improve its ability to use fat for energy so you can exercise for longer, while higher-intensity exercise may increase your body’s ability to supply more oxygen and use the supplied oxygen more quickly and efficiently. 

Likewise, to increase muscular endurance, you need to do strength training, focusing on doing more repetitions with lighter weights, Rulon says. Aim to do two to three full-body strength workouts a week, as recommended by the American College of Sports Medicine. 

How Long Does It Take to Build Endurance?

How long will it take for you to improve your physical endurance? It varies from one individual to another, but in general, Rulon says that if you’re doing three 30-minute workouts a week, you can expect to see improvements in cardiovascular endurance in eight to 12 weeks. With muscular endurance, many studies show that there’s improvement after six weeks, she says.

Keep Pushing Your Boundaries to Build Endurance

Whether you’re training for cardiovascular or muscular endurance, or both, it’s important that you’re really challenging your body and signaling the need for your body to adapt (aka get stronger and be able to withstand that weight and/or activity for longer!). And as soon as you adapt—an activity becomes easy to do or you stop noticing progress—it’s time to change something again. Maybe you start running for 10 minutes longer, push harder with some faster sprints at the end, or go for runs more frequently throughout the week. Otherwise, it’s easy to get stuck on a plateau, he explains.

The Importance of Recovery and Rest

The catch is that it’s also extremely important to find a good balance: Don’t overdo your training, otherwise you could risk injuring yourself, Rothstein says. Recovery begins as soon as you’ve ended a workout, and that recovery time is crucial for building endurance. “Exercise that stimulates the need for adaptation is going to break your body down and weaken you temporarily,” he explains. “During the rest and recovery phase you build back to be stronger.” 

But people often get so excited about forging forward with their fitness that they ignore cool-down practices and necessary rest days—and that’s a mistake. Take at least one day off from structured exercise every week, maybe more if you’re new to exercise or doing extremely high-intensity workouts. 

Recovery includes getting enough sleep, too. “Sleep allows your body to recover and restore itself,” Rulon says. In fact, sleep and exercise have an interesting relationship, as sleep quality has been shown to help with exercise, while exercise may potentially help improve your sleep quality, Rothstein adds. The general sleep recommendation for adults is to get seven to nine hours of sleep every night.