Straight leg running is an effective cardio and conditioning exercise. Begin by standing in place with your arms by your sides, engage your core, and keep your chest up. Start running in one spot, but unlike regular running, keep your knees straight. Land on the balls of your toes and flick your toes back out in front.

Half jacks are a modified version of jumping jacks that emphasize lower body movement. Begin in a standing position with your feet about half a shoulder-width apart, maintaining a tight core and an upright chest. Perform this exercise by quickly jumping your feet outward to approximately two shoulder widths apart and then back inwards, completing one repetition.

High knees are an effective cardiovascular exercise that elevates your heart rate and aids calorie burning. To perform high knees, start in a standing position with your feet hip-width apart. Begin running in place, bringing your knees up toward your chest as high as possible while simultaneously pumping your arms. Maintain an upright chest, engage your core, and strive to land lightly on the balls of your feet.