Have you ever heard of HIIT? HIIT (High-Intensity Interval Training) is the best fat burning workout within a short duration. You just spend around 15 minutes for weight loss and muscle building a day. Here are some HIIT exercises to burn calories. Are you ready?

(1) High Knees
High knees can improve your coordination and flexibility of the lower body and strengthen your core and legs. Lift your knees as high as possible to raise the intensity. Steps: (1) Stand up straight and look forward. Keep your feet hip-width apart. (2) Lift your right knee up and raise your left arm. (3) Quickly switch to lift your left knee up before your right foot lands. And, raise your right arm immediately. (4) Repeat the movement alternatively at high speed. Duration: 2 minutes
(2) Push-ups
Push-ups are one of the best bodyweight exercises to strengthen your core and lower body. You can perform it without equipment. Steps: (1) Start in a high plank position with your hands under the shoulders. Place your palms flat on the ground and point your fingers ahead. Keep your feet shoulder-width apart and ground your toes to stabilize your lower body. (2) Inhale. Bend your elbows to lower your body slowly until your chest is just above the ground. Keep your back flat and your body in a straight line. Do not let your butt dip. (3) Exhale. Come up back to a high plank position. (4) Repeat the movement. Duration: 45 seconds
(3) Burpees
Burpees are a total body exercise to build all muscles of your body. Steps: (1) Stand up straight. Keep your feet hip-width apart. Weight on your heels. Put down your arms at your sides. (2) Start in a partial squat position. Bend your knees. Push back your hips. Keep your spine neutral. Place your palms in the front and support your lower body to extend your legs behind. Ground your toes to stabilize your lower body. (3) Do a push-up. Bend your elbows to lower your body slowly until your chest is just above the ground. Then, come up back to a partial squat position. (4) Do a frog jump. Jump back your legs and land outside of your palms. Do a jump squat with raising up your hands above your head. (5) Repeat the movement. Duration: 4 minutes