Kick Start Your Core
Lie on your back on the rebounder, your feet flat on the floor with your hands supporting your head. Then raise your feet a few inches off the floor. Much like you would when performing normal bicycle crunches, straighten your left knee while bending your right knee to your chest -- use your abs to lift and turn your upper body to bring your left elbow to your right knee. Repeat with right knee in a bicycle peddling motion. Perform three sets of 12 repetitions.
Reach for the Stars
These exercises mimic jumping jacks and are excellent for core strength. Stand with feet together and arms to your sides. Jump with feet apart and simultaneously raise your arms above head, then jump back into staring position, ensuring that your feet do not land on the frame. Breathe out when you jump back into start position, and breathe in when you jump out. These are quick mini jumps. Engage your abs -- your back should be straight at all times. Perform three sets of 20 jumps.
Raise 'em High!
Similar to standing crunches, knee raises help build a strong core and tone your abs. While you're in midair, focus on engaging your abs. Stand with feet together, arms loosely to sides and begin jogging at a moderate pace. While jogging in place, alternate your knees, lifting them at hip level while your opposite elbow meets opposite knee. This mimics a standing crunch. Perform three sets of 20 repetitions on each knee.
Lie comfortably on your back, hands on your chest and lift your legs up toward the sky. Bend knees slightly. Use your abs to lift your body, legs should be over your head and body should create a U shape. Your shoulders should lift off the trampoline slightly. Hold the position then come back to the starting position. While your body is in the U position, tighten your abs so you feel them crunch. Your breathing should be steady, breathing out as you come into position, breathing in as you lower your legs. Perform three sets of 15 raises.