Which is a type of cardiorespiratory exercise?

• A. Cardio machines
• B. Weightlifting
• C. Isometric holds
• D. Stretching

Answer: (A)

Cardiorespiratory exercise is sustained, rhythmic activity that uses large muscle groups and keeps the heart rate and breathing rate elevated for a period of time. Cardio machines fit this definition because they are designed for continuous aerobic work, allowing you to keep moving at a steady pace (like on a treadmill, cycling bike, elliptical, or rower) to train the heart and lungs and build endurance.

In contrast, weightlifting is mainly about building muscular strength and power through short bouts of effort; isometric holds involve maintaining a position with little or no movement; and stretching focuses on improving flexibility. While those activities have their own benefits, they don’t provide the ongoing, whole-body aerobic stress that characterizes cardiorespiratory exercise, which is why cardio machines are the type of cardiorespiratory exercise.