Muscle Ventures Video Analysis

In this video analysis (Quicktime, 7.6 MB; Google video, no download), Nancy and I (Bud) present the BOSU jackknife, an ab exercise that uses both a BOSU (a sort of Swiss Ball chopped in half) and a medicine ball. The exercise keeps constant tension on the abs and like our Swiss Ball jackknife has a significant stabilization component that works the obliques. If you're a fan of Blaine Moore's series on bridge exercises, then this exercise might be a nice next step up the ladder of difficulty.

To perform this exercise, position your back on the center of the BOSU as Nancy and I illustrate in Photos 1 and 3 on the left. Then grasp the medicine ball directly over your head. Nancy and I both use a 9 lb. medicine ball. Choose a light one to start. It adds difficulty to the exercise by lengthening the torso (i.e., the length of the lever you are exerting force on) and adding weight to boot.

To execute the exercise, place one of your feet on the ground for stability and stretch the other out flat. This second foot should be close to the floor but not touching. Then, as Nancy and I illustrate in Pictures 2 and 4, simultaneously perform a crunch with your upper torso (holding the ball over your head) and lift the knee of your extended leg to touch your elbows. Next, reverse the movement to return to the start position. Make sure the extended leg does not touch the floor. Repeat 15 times for one leg extended before switching to the other.

If executed properly, this exercise will keep constant tension on the abs and give you a real abs workout. Cheating in this exercise involves removing tension from the abs. One way to do that is to touch your extended foot to the floor. When you first try this exercise, you may find yourself having to touch your extended foot to the floor out of necessity, but you should try to avoid it. Another way to cheat is to let your arms do some of the work in moving the ball up and down. If you carefully examine the strip of photos on the left, you will notice that Nancy and I keep the ball in a constant position relative to our heads.

Additional Links

• The BOSU is used for many different balance exercises.
• Karen Voight has a bicycle exercise on the BOSU that might be considered the next step after what Nancy and I illustrate here.

Twisting overhead leg raises with medicine ball work the full abdominals with a bonus emphasis on the obliques due to a twist at the end. You can view our analysis of this exercise either by downloading the Quicktime movie (3.4 MB) or on Google Video without downloading. The video shows me (Bud Gibson) performing the exercise while Nancy Arnold coaches me.

The equipment for this exercise is simple. All you need is a medicine weighing 12 to 15 lbs. In a pinch, you could use a large rock or a light dumbbell. The difficulty of exercise lies in coordinating a series of movements to transition the lower half of your body through a rather large range of motion with your only leverage the 12 lb. or so weight in your hands.

The exercise is performed as follows. Lay flat on the ground. Grasp the ball between your hands and hold it just above your head as I illustrate in the first picture on the left. Then, raise your legs straight up. When they are perpendicular (second picture on the left), you twist your torso so that one of your knees goes over and touches the opposite elbow (third picture on the left). You then lower your legs so that they come down and almost but not quite touch the floor (1st picture on the left again). That way, you maintain constant tension on the abdominals. If possible, repeat at least fifteen to twenty times alternating the knee you touch to the opposite elbow.

There are two major sources of difficulty in this exercise. The first is coordinating the series of movements it takes raise your legs. If you start moving your knees over to the opposite elbow before reaching perpendicular, you will tilt off balance and fall on your side, failing to stress the obliques. To achieve the full effect on the obliques, the twist must come at the end after the legs have passed perpendicular.

The second source of difficulty is that your only leverage is the medicine ball you hold in your hands. The lighter the ball, the harder it is to stabilize the movement.

Additional Links

I believe this exercise to be unique to Nancy and myself. However, I was able to find some comparable exercises and a whole series of medicine ball exercises that may be of interest to readers.

• Shapefit provides a series of medicine ball and other exercises to strengthen the core. This exercise is billed as a medicine ball leg raise but is in fact a simultaneous leg and arm raise to touch in the center.
• EXRX provides a balance training kit for $87 that illustrates a number of core training exercises using the medicine ball.
• Everything Track and Field provides a guide for purchasing a good medicine ball.