This 15-minute equipment free workout with Coach Kim will warm up your body and boost your metabolism through lunges and lower core work. Whether you believe in the freedom to #bendtheknee during the National Anthem or not, lunges are a compound exercise which everyone should be able to do. They also elevate your heart rate which helps you fight fatigue during those tough times of the day. A longer version will be available on the inSHAPE Fitness Show later this week.