How to Use the Vertical Knee Raise Machine

Warm-up up your tummy muscles with targeted movements, such as torso rotations. Spread your feet shoulder-width apart then swing your arms and twist your torso to the left so you end up with your weight on the left foot. Essentially, you are mimicking the a golf club or baseball bat swing. Next, rotate your torso and swing your arms to your right side. As you start warming up, slowly increase your range of motion. Repeat 15 times on each side.

Incorporate side bends in your warm-up. Stand upright with your feet in a shoulder-width stance and your arms extended along your sides. Bend sideways from your waist and reach with your right hand down the side of your right leg as far as you can so you feel a stretch along the left side of your waist. Repeat this on your left side and complete 15 repetitions on each side. Try to reach a little further down each time.

Position yourself in the knee raise machine. Stand on the footrest, place your back against the backrest, and then bend your elbows 90 degrees and place your forearms on the designated pads so you can hold onto the handles with your hands. Step off the footrest and straighten your knees so your body is in a vertical line from your head to your toes and you're supporting yourself with your forearms. Tighten your abdominal muscles to take on the starting position.

Perform knee raises. Bend your knees and slowly bring them up toward your chest as far as you can without looking down or arching your back. Pause for one second before returning your legs to the starting point. Repeat this 10 to 25 times.

Target your love handles or obliques with the oblique twist. Bend your knees and slowly raise them up toward your chest. When your thighs are almost parallel to the floor, twist your knees to the right as if to bring them toward your right shoulder. Pause for one second then slowly return your knees to the center and then straighten your legs so you come back to the starting position. Repeat the exercise, but this time, twist your knees toward your left shoulder. Complete 10 to 25 repetitions.

Scissor your legs to add variety to your routine. Slowly raise your right leg straight in front of you, keeping your knee straight, your toes pointed and your back against the backrest. When your leg is parallel to the floor, pause for one second then return it to the starting position. Immediately raise your left leg to the parallel position and pause for one second before returning it to the starting position. Continue alternating your legs to complete 10 to 25 repetitions.

Incorporate straight leg raises if you're up for a challenge. Instead of bending your knees, keep them straight. Use the lower part of your rectus abdominis to slowly raise both legs up in front of you. Face forward, keep your back against the backrest and point your toes. When your legs are parallel to the floor, pause for one second and then return them to the beginning position. Perform 10 to 25 leg raises. Alternatively, hold your legs up in front of you as long as you comfortably can with perfect form.

Perform light stretches to cool down. Come down on all fours or bend over and place your hands on your knees. Look down and round your back as much as you can in a cat-like manner. Hold this position for a few breaths, and then look up and arch your lower back as much as you can for a couple of breaths. Do this at least five times.