Only 25% of Americans get the amount of physical activity experts recommend for good health. For the average American, 75-150 minutes a week of aerobic exercise and two days of muscle strengthening, the amount the American Heart Association encourages, can feel daunting — especially if you spend a lot of your day sitting.

A new study published in the European Heart Journal offers an encouraging message: How intensely you move may matter alongside how much you move.

The study’s participants experienced the greatest benefits when vigorous activity accounted for at least 4% of a person’s total physical activity. That doesn’t translate neatly into one prescription for everyone, but it suggests even brief bursts of harder effort may make a difference.

“The impact just a small amount of vigorous physical activity (VPA) can have on someone’s health is astonishing,” said Dr. Dale Daly, a cardiologist at Novant Health Heart & Vascular - Physicians Plaza in Hilton Head, South Carolina. Daly sat down with us to unpack the importance of these findings for the everyday American.

What are the health benefits of vigorous exercise?

These findings highlight two important ideas about vigorous exercise.

First, exercise intensity may matter independently of how much activity a person gets. Second, doing VPA for just 4% of your workout is associated with a lower incidence of eight conditions:

• Major cardiovascular events, such as a heart attack
• Atrial fibrillation, a specific type of arrhythmia
• Type 2 diabetes
• Immune-mediated inflammatory diseases
• Metabolic dysfunction-associated steatotic liver disease, commonly called fatty liver disease
• Chronic respiratory disease
• Chronic kidney disease
• Dementia

It is also associated with lower risk of overall mortality.

What is considered vigorous physical activity?

VPA will look different for everyone, as everyone’s physical fitness varies. This is important to keep in mind. I have patients who lead largely sedentary lifestyles come into my office, worried that they have a severe heart condition, because they’re getting out of breath walking.

Sometimes, after evaluating them and ruling out a medical problem, I find that their body simply isn’t accustomed to the demands of physical activity. We call that deconditioning.

Someone who leads a largely sedentary lifestyle is going to have a very different idea of VPA compared to a marathon runner. For all individuals, it’s anything that really gets your heart rate up to the point where you’re breathing hard enough that talking is difficult.

Some common examples include:

• Running
• Jogging
• Cycling
• Swimming laps
• Kickboxing

However, it’s truly different for everyone, and your VPA standards will change as you exercise more often.

Does adding short periods of vigorous activity offer benefits beyond what moderate-intensity activity can?

While this research suggested VPA could provide additional benefits per minute, that doesn’t mean moderate activity is ineffective or that brief bursts of VPA can completely replace longer, moderate-intensity activity.

People who accumulated greater amounts of moderate activity also experienced lower risks. The encouraging finding is that people may not need to complete lengthy, high-intensity workouts to benefit from greater intensity.

Continue using moderate activity to work toward your weekly goal and, when it is safe and appropriate, incorporate brief vigorous intervals that leave you breathing hard.

Why might brief bursts of VPA have an outsized impact on our health?

When you exercise vigorously, your body has to adapt quickly: your heart pumps harder, your breathing increases and your muscles demand more oxygen and energy. Those brief challenges may produce a stronger physiological response per minute than moderate activity.

Is vigorous exercise safe for everyone?

Not at the same level or starting point. Most healthy adults can gradually incorporate more intensity, but people who have been inactive or have certain health conditions may need to begin with moderate activity and consult their health care provider before progressing.

Vigorous activity is also relative to the individual: running may be vigorous for one person, while climbing stairs or walking uphill may be vigorous for someone else.

How can you start vigorous exercise safely if you’re out of shape?

If you’re ever unsure if a certain type of activity is appropriate for you, consult your primary care physician.

Stop exercising and seek medical guidance if you experience chest pain, fainting, heart palpitations or unusual shortness of breath. New or severe chest pain may require emergency care.

If you’re cleared, my recommendation is to take things slowly. Push yourself, but don’t punish yourself. Exercise should be rewarding and sustainable. You may also want to take group classes or work with a personal trainer if you’ve been away for a while. Most importantly, just start.

Is moderate exercise still beneficial if you can’t do vigorous exercise?

Very beneficial. During a moderate-intensity activity, you should be able to carry a conversation, but you will feel your heart rate speed up. A common example is a brisk walk. Vigorous activity may provide greater benefits per minute for certain outcomes, but people do not need to exercise vigorously to improve their health.

What are some easy ways to add vigorous activity to your day?

• Walk quickly up a hill on your next walk
• Take the stairs instead of the elevator
• Jog for part of your walk
• Ride at a faster pace for parts of an otherwise leisurely bike ride
• Jump rope before or after work

It sounds cliché — take the stairs instead of the elevator — but the goal isn’t to find a “hack.” It’s to incorporate small periods of VPA into your day so you’ve easily gotten that small fraction that can move the needle under your belt by the end of the week.

If you want to do more and go to a spin class or go for an interval-based run, that’s great, too.

Remember: none of this exists in isolation. Vigorous activity is only one part of protecting your long-term health. A nutritious diet, recommended preventive care and management of factors such as cholesterol and blood sugar still matter.

What’s one thing you want anyone reading this to understand about vigorous physical activity?

Research suggests that even a few minutes of vigorous activity can contribute to a lower risk of chronic disease. That doesn’t mean more activity is irrelevant, but I understand that we’re all working with time, health and resource constraints. Use the time and abilities you have to make sustainable improvements. Every little bit counts.