Cardio, short for cardiovascular or aerobic exercise, is any activity that raises your heart rate and breathing for a sustained period: brisk walking, running, cycling, swimming, rowing, dancing or even energetic gardening. Most people know it’s “good for the heart”, but its benefits reach almost every part of the body and mind.
In fact, cardiorespiratory fitness, a measure of how well your heart and lungs deliver oxygen during exercise, is one of the strongest predictors of how long and how well you’ll live. A 2024 overview of meta-analyses in the British Journal of Sports Medicine, covering more than 20 million observations, found that people with high fitness had roughly half the risk of dying from any cause compared with people with low fitness. Here are 10 cardio benefits you should know, and how to get them.
How much cardio do you need?
US and WHO guidelines recommend that adults get:
- 150 to 300 minutes a week of moderate-intensity aerobic activity, or
- 75 to 150 minutes a week of vigorous-intensity activity, or a combination
- Plus muscle-strengthening activity at least twice a week
The talk test is an easy way to judge intensity. During moderate activity, you can talk but not sing. During vigorous activity, you can only say a few words before needing a breath. Even small amounts count: research shows that just 75 minutes a week of moderate activity is linked with a meaningfully lower risk of early death.
1. A stronger heart and better circulation
Cardio trains your heart to pump more blood with each beat, so it doesn’t have to work as hard at rest. Regular aerobic exercise improves the flexibility of blood vessels, raises HDL (“good”) cholesterol, lowers triglycerides and reduces the risk of heart disease and stroke. According to the WHO, regular physical activity lowers the risk of heart disease and stroke by around 19%.
2. Lower blood pressure
A large 2023 network meta-analysis of 270 randomized trials in the British Journal of Sports Medicine confirmed that aerobic exercise, high-intensity interval training, resistance training and isometric exercise (like wall sits and planks) all significantly lower resting blood pressure. Aerobic exercise typically lowers systolic pressure by several points, comparable to some medications in people with mild hypertension. Combining cardio with a little isometric work may give the biggest effect.
3. Better blood sugar control
When you exercise, your muscles take up glucose from the blood for fuel, and regular cardio makes your body more sensitive to insulin for hours afterward. That lowers the risk of type 2 diabetes and helps people who already have it manage their blood sugar. Even a 10 to 15 minute walk after meals can blunt blood sugar spikes.
4. Easier weight management
Cardio burns calories and, combined with a healthy diet, supports weight loss and especially weight maintenance. People who keep weight off long term tend to stay physically active. Research also shows that fitness matters for health at every size: a 2025 analysis in the British Journal of Sports Medicine found that higher fitness was linked to lower mortality risk across body weight categories.
5. A happier mood
Aerobic exercise releases endorphins and other brain chemicals that improve mood and reduce feelings of stress. Regular cardio is linked with a lower risk of depression and can reduce symptoms in people who already have depression or anxiety, working well alongside other treatments.
6. Sharper thinking and memory
Cardio increases blood flow to the brain and supports the growth of new brain cells, particularly in the hippocampus, which is important for memory. Higher fitness is linked to a lower risk of dementia and cognitive decline. Even a single session can improve focus and attention for a couple of hours.
7. Better sleep
Regular aerobic exercise helps you fall asleep faster and spend more time in deep, restorative sleep. Morning or afternoon exercise outdoors in daylight can also help regulate your body clock. Just finish intense sessions a couple of hours before bed if they leave you wired. For more on sleep, read our article on omega-3s and insomnia.
8. A stronger immune system
Regular moderate exercise is linked with fewer respiratory infections and may improve how well vaccines work. It helps immune cells circulate through the body more efficiently. Very intense, prolonged training without enough rest can temporarily suppress immunity, so balance matters. Learn more about the signs of a weak immune system.
9. More energy and stamina
As your heart, lungs and muscles become more efficient, everyday activities like climbing stairs, carrying groceries or playing with kids feel easier. Many people find that regular cardio reduces fatigue rather than adding to it.
10. A longer, healthier life
A landmark 2018 study in JAMA Network Open of more than 122,000 patients who completed treadmill tests at the Cleveland Clinic found that low fitness was associated with a higher risk of death than smoking, diabetes or heart disease, and there was no upper limit to the benefit of higher fitness. Each one-unit increase in fitness (one MET) is linked to roughly an 11% to 17% lower risk of death. The encouraging news is that fitness can improve at any age.
Types of cardio to try
- Low impact: walking, cycling, swimming, water aerobics, elliptical and rowing. Easier on joints and great for beginners.
- Higher impact: running, jumping rope, dance fitness and team sports. Build bone strength but need a gradual build-up.
- Interval training (HIIT): short bursts of hard effort followed by recovery. Time-efficient and very effective for fitness, but best added once you have a base.
- At home: no gym needed. Try our home cardio workouts.
Running is one of the most accessible options; see how running can boost your quality of life.
A simple 4-week plan for beginners
- Week 1: walk briskly for 10 to 15 minutes, 5 days a week.
- Week 2: walk for 20 minutes, 5 days a week. Add a gentle hill if you can.
- Week 3: walk for 25 to 30 minutes, 5 days a week, including 3 to 5 one-minute faster intervals.
- Week 4: 30 minutes, 5 days a week, mixing in a different activity, such as cycling or swimming, once or twice.
By the end, you’ll be meeting the 150-minute guideline. A fitness tracker can help you monitor steps, time and heart rate. If you’re heading to the gym, our gym tips for beginners will help.
How to find your heart rate zones
If you like numbers, heart rate is a useful way to guide intensity. A common estimate of maximum heart rate is 220 minus your age, though individual values vary a lot. Based on that estimate:
- Moderate intensity: roughly 50% to 70% of your maximum heart rate. For a 40-year-old (estimated maximum 180), that’s about 90 to 126 beats per minute.
- Vigorous intensity: roughly 70% to 85% of your maximum. For the same 40-year-old, about 126 to 153 beats per minute.
Some medications, especially beta-blockers, lower heart rate, so the talk test or how hard the exercise feels may be more reliable for you. Over weeks and months, you’ll notice that the same pace feels easier and your resting heart rate may drop slightly, both signs that your cardiovascular fitness is improving.
Don’t let the numbers become a barrier, though. For most people, simply moving at a pace that makes you breathe harder but still able to talk is all you need to start getting the benefits.
Staying safe
- Warm up for 5 minutes and cool down gradually.
- Increase time or intensity by no more than about 10% a week.
- Drink water, especially in hot weather, and wear supportive shoes.
- Stop and seek medical help if you feel chest pain or pressure, severe breathlessness, dizziness or an irregular heartbeat.
- Talk to your doctor before starting if you have heart disease, diabetes, high blood pressure, are pregnant or have been inactive for a long time.
Pair your cardio with a heart-healthy diet; our list of cholesterol-lowering foods is a good place to start. For the wider picture, read about the benefits of regular physical activity.
Common questions
How much cardio should I do each week?
Aim for 150 to 300 minutes of moderate cardio or 75 to 150 minutes of vigorous cardio each week, plus strength training twice a week.
Is walking good cardio?
Yes. Brisk walking is moderate-intensity cardio and one of the easiest ways to improve heart health, mood and fitness.
Can cardio lower blood pressure?
Yes. A 2023 meta-analysis of 270 trials found aerobic exercise and other forms of training significantly lower resting blood pressure.
Is HIIT better than steady cardio?
HIIT improves fitness efficiently in less time, while steady cardio is easier to sustain and gentler on the body. Both work; the best one is the one you’ll keep doing.
What is the best time of day for cardio?
Any time you can do it consistently. Morning sessions outdoors may help sleep, but avoid intense workouts right before bed if they keep you awake.
This article is for general information and isn’t a substitute for medical advice.
Explore more cardio workouts in our diet and cardio workout section.
