If you can comfortably jog, walk, or bike a few miles, you likely have good endurance fitness. Some people, like marathoners, have very high levels. Exercising regularly is the best way to build endurance fitness. But genetics matters, too, and AncestryDNA® Traits looks at three genes associated with endurance fitness, specifically PPARAGC1β, HIF1A, and ADRB2.

What Is Endurance Fitness?

Aerobic activity builds endurance fitness by increasing your heart rate and making you breathe more (aerobic means “with oxygen"). The more aerobically fit you are, the more efficiently your heart pumps and the oxygen can get to your muscles. Brisk walking, running, swimming, cycling, cross-country skiing, jumping rope, and dancing are examples of endurance exercise.

Also, different types of muscle fibers support different types of exercise. For endurance activities, your body relies on slow twitch muscle fibers, which resist fatigue and have more blood supply. By contrast, power sports like weightlifting or sprinting rely on fast twitch muscles.

How Endurance Fitness Keeps Us Healthy

Building endurance fitness has many health benefits, including reducing your risk for heart disease and helping you better control your blood sugar (which reduces your risk for type 2 diabetes). Aerobic exercise also helps prevent many types of cancer, improves people's quality of life, and helps people of all ages manage depression and anxiety.

This is why the Department of Health and Human Services recommends that adults get at least 150 minutes—or 2.5 hours—of moderate intensity aerobic exercise each week (brisk walking is moderate intensity). People who want to get the most benefits should aim for 300 minutes—or 5 hours—per week.

Endurance Fitness and Genetics

Scientific research shows that genetics plays a part in endurance fitness. In studies comparing athletes and non-athletes, scientists have linked several hundred variations in genes to differences in athletic performance.

AncestryDNA® Traits looks at three genes (PPARAGC1β, HIF1A, ADRB2), where differences in the genes are associated with differences in endurance fitness. This may affect things like muscle performance, body oxygen levels, and heart rate.

Importantly, the scientific consensus is that each genetic difference likely only makes a small contribution to someone's overall endurance fitness; training, effort, and resources will factor more into athletic success.

Interesting Facts About Endurance Fitness

How do you explain families of talented runners? It's likely a combination of genetics plus environmental and behavioral factors. For example, families and communities that live at high elevations tend to have increased lung capacity compared to lower-elevation communities. So can living in a city with a top-notch running program, or parents making a habit of running with their kids.

Another factor is VO2 max, or the maximum amount of oxygen your body can use during exercise. The higher your VO2 max, the better endurance you'll have. A high VO2 max also means a lower risk of heart disease. But you can still increase your VO2 max with regular exercise.



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