Cardiovascular exercise, often referred to as cardio, is any form of activity that raises the heart rate and keeps it elevated for a sustained period. While cardio is commonly associated with weight loss, its primary purpose is to improve cardiovascular health by strengthening the heart and lungs. This improvement plays a key role in reducing the risk of conditions such as heart disease, high blood pressure, type 2 diabetes, metabolic syndrome, obesity, strokes, and certain cancers. Weight-bearing aerobic activity, such as walking, can also contribute to maintaining bone health.
What is cardio?
Cardio is defined by its effect on the cardiovascular system rather than the specific movement involved. Any exercise that increases heart rate and breathing for an extended period falls into this category. Beyond calorie expenditure, cardio supports long-term health by improving how efficiently the heart pumps blood and how effectively the lungs deliver oxygen throughout the body.
What does cardio exercise involve?
Cardio exercise, sometimes called aerobic exercise, involves rhythmic movements that elevate heart rate and breathing. Activities can range from walking and running to sports such as tennis. As long as the activity raises the heart rate and results in light to moderate sweating, it can be considered cardio.
What distinguishes cardio from strength training is the reliance on the aerobic energy system. During cardio exercise, the body uses oxygen to break down glucose within the muscles, supplying energy over longer durations. Individual cardio capacity can vary and is influenced by factors such as genetics, age, and biological sex.
How often should I do cardio exercise?
General physical activity guidelines recommend that adults aim for at least 150 minutes of moderate-intensity cardio exercise each week. This total does not need to be completed in one session and is more manageable when spread across several days. Shorter sessions accumulated throughout the day can still contribute to overall cardiovascular benefit.
What are the benefits of cardio?
The most significant benefit of cardio is improved heart and lung function, which helps lower the risk of many chronic health conditions. Cardio also supports calorie expenditure and can form part of a structured weight management approach. In addition, regular cardio activity has been linked to improved mental wellbeing, increased lifespan, and reduced risk of cognitive decline.
- Improves heart and lung efficiency
- Reduces the risk of cardiovascular disease and metabolic conditions
- Supports mental health and mood regulation
- Helps manage stress levels
- Contributes to bone density when weight-bearing activities are used
- Enhances lung capacity
- Supports sleep quality
- Aids calorie and fat expenditure
Types of cardio exercise
Cardio can take many forms and may be performed with or without equipment. Common examples include walking, jogging, swimming, cycling, rowing, and skipping. These activities vary in intensity and impact level, making it possible to select options that align with individual fitness levels and physical considerations.
For those new to exercise or returning after a period of inactivity, lower-impact activities such as walking or cycling are often suitable starting points. Intensity and duration can then be increased gradually over time.
What equipment can be used for cardio?
A wide range of gym equipment is designed specifically to support cardio training. In shared training environments, these machines allow users to control variables such as speed, resistance, and incline, making them adaptable for different abilities and training goals.
Treadmills are commonly used for walking and running, offering adjustable speed and incline to vary intensity. Cross trainers provide a lower-impact alternative that reduces joint stress while maintaining a full-body movement pattern. Exercise bikes, including upright, recumbent, and indoor cycling models, replicate cycling movements with different seating positions. Stair climbers simulate stair ascent and place emphasis on lower body engagement, while rowing machines combine upper and lower body effort to deliver full-body cardio training.
The different types of cardio
Cardio training is often grouped into two broad categories based on duration and intensity.
- Long cardio, also known as low-intensity interval training, typically lasts longer than 30 minutes and is performed at a steady, manageable pace. This type of cardio supports endurance development.
- Short cardio, commonly referred to as high-intensity interval training, involves shorter sessions under 30 minutes performed at higher intensity. These sessions focus on speed, power, and time efficiency.
Cardio intensity
Cardio intensity is commonly measured as a percentage of maximum heart rate. The appropriate intensity level depends on individual fitness, experience, and training goals.
How intensely should you work?
- High intensity sessions typically fall between 70 percent and 85 percent of maximum heart rate. These workouts are challenging and are usually sustained for shorter durations.
- Moderate intensity sessions fall between 50 percent and 70 percent of maximum heart rate and can be maintained for longer periods while still feeling demanding.
- Low intensity sessions remain below 50 percent of maximum heart rate and are generally comfortable, making them suitable for recovery or longer-duration activity.