The power of cardio for all-round fitness
Discover the significance of cardio in achieving overall fitness and uncover the incredible benefits it brings. Explore the shortest, most effective cardio workouts, including HIIT and REHIT.
Why cardio matters
7 cardio exercise benefits.
- Reduces heart disease risk – Improves heart disease risk factors: high blood pressure, obesity, poor aerobic fitness.
- Reduces type 2 diabetes risk – Helps regulate insulin and blood glucose levels.
- Reduces stroke risk – Improves stroke risk factors: high blood pressure, obesity, type 2 diabetes.
- Regulates mood – Improves symptoms of anxiety and depression.
- Reduces cancer risk – Helps reduce the risk of developing certain cancers.
- Maintains brain health – Slows the natural cognitive decline associated with aging.
- Improves sleep – Improves both sleep duration and quality
The science of cardio
- As your muscles begin to work, they need more oxygen and fuel for energy.
- Your heart rate quickens to pump more oxygenated blood and glucose to your muscles.
- Your muscles use available glucose from your blood as fuel.
- Your muscles begin to break down glycogen (stored glucose) for energy.
- Your insulin sensitivity rises, helping your muscles drive glucose into your cells for energy.
- Your breathing speeds up from around 15 breaths a minute to 40–60 breaths a minute to draw more oxygen into your body.
- Your skin looks flushed as your blood vessels expand to improve blood flow to your muscles.
- Waste products are created from breaking down glucose, glycogen, and oxygen for energy.
- Your blood vessels carry the waste products away.
- Your body starts to break down stored fat for additional energy.
Short, efficient cardio

Research show you’ll get more fitness benefits, in less time, from interval training.
HIIT
An elliptical workout not only helps you to burn calories and lose weight, but it is also great for strengthening muscles and improving cardiovascular health. It engages both the lower and upper body muscles, providing a whole body workout.
HIIT benefits
Saves you time
Burns more calories
Increases metabolic rate
Stabilizes heart rate and blood pressure
Increases endurance
HIIT workout
20-minute HIIT workout
- Jumping Jacks – Start by standing upright with your feet hip width apart and your arms at your sides. Jump your feet out while raising your arms.
- Bodyweight Squat – Stand straight with your feet hip-width apart. Lower yourself down (as if sitting in an invisible chair). Straighten your legs and lift back up and repeat.
- Mountain Climber – Start in a high plank position, with your wrists directly under your shoulders, core engaged, hips level, and legs extended straight behind you. Draw your right knee to your chest, return to your starting position, and immediately draw your left knee to your chest. Return to your starting position and continue to alternate, moving quickly.
- Jump Squat to Twist – Start with your hands behind your head and feet wider than hip-width and do a squat. As you stand, lift your left knee toward your chest and across your body to tap your right elbow. Return elbow and left leg back to starting positions and do a squat. Alternate sides.
- Push-Up With Tuck – Start in a high plank position. Bend your elbows and lower your chest to the floor. Drop to your knees if needed. Push through the palms of your hands to straighten your arms. At the top of your push-up, bring your right knee toward your right elbow, then immediately return to a high plank position. Alternate sides.
- Bicycle With Punch – Lie faceup with your shins parallel to the floor, knees bent to 90 degrees, and stacked over your hips. Hold your hands in fists at your chest. Use your abs to raise your shoulders off the floor. Bend your left knee in toward your chest, while simultaneously straightening your right leg and punching your right arm toward the ceiling. Then twist to bring your right knee in, simultaneously straightening your left leg and punching your left arm into the air. Continue alternating sides. Go at a slow, steady pace so you can really twist and feel your abs working.
- Drop Lunge – Stand with your feet shoulder-width apart, core engaged, and jump your right foot back behind you and bend both knees to 90 degrees to sink into a lunge. Return to your starting position by pushing off your right foot and jumping forward, bringing your feet together. With your feet together, hop up, and jump your left foot behind you so that you land in a staggered stance with your left foot back. Immediately sink into a lunge by bending both feet to 90 degrees. Jump both feet together to return to your starting position. Continue to alternate sides.
- Shoulder Tap – Stand in a high plank position, with your palms flat on the floor, shoulders stacked directly above your wrists. Lift your right hand. Place your right hand back down on the floor and immediately lift your left hand to tap your right shoulder. Continue to alternate sides.
- Jackknife – Lie faceup with your legs extended and arms overhead so that all of your limbs are resting on the floor. Engage your core and lift both arms and legs a few inches off the floor to come into a hollow hold position. Now bring your knees to your chest, simultaneously bringing your arms toward your legs and wrapping your hands lightly around your shins. Keep your core tight and do not grip your shins or hug your knees in order to achieve the crunch. Extend your arms and legs to return to the hollow hold position.
The shortest, most effective cardio
What is REHIT?

CAROL’s the only bike with REHIT, the next-level HIIT workout that gives you double the health benefits, in just 10% of the time.

REHIT creates the most potent training stimulus with just 2x20-second sprints.
How does REHIT work?
What are the health benefits of REHIT?
- Improve VO2max by up to 12%
- Lower blood pressure by 5%
- Increase good cholesterol by 6%
- Lower risk of type 2 diabetes by 62%
- Reduce triglycerides (fat found in blood) by 10%
- Reduce blood sugar by 2%
How to do REHIT
- Gently jog for 2 minutes to warm up
- Sprint as fast as you can for 20 seconds
- Gently jog for 3 minutes to recover
- Sprint as fast as you can for 20 seconds
- Gently jog for 3 minutes to cool down
How to really do REHIT


