The Navy SEAL Physical Fitness Guide - Uniformed Services ...

Another change that should be incorporated in an abdominalworkout is the addition of a 2 inch thick towel or an “Ab Mat” beneaththe lower spine. The anatomical range of motion for the abdominals is from 30˚extension to approximately 75-90˚ flexion (Figure 8-3). When performing abdominalexercises on a flat surface (i.e., the deck) you are limiting your exercise to only half thenormal abdominal range of motion. In other words, when abdominal exercises areperformed on a floor, deck, or mat, only half the work necessary to develop abdominalstrength is being done. Abdominal strength is best developed by exercises performedwithin the full anatomical range of motion, with some curve in the lumbar spine (i.e., towelor Ab Mat) as opposed to a flat back. By placing a towel or the Ab mat beneath your lowerspine you can achieve the right form for these exercises (see Figure 8-4).Figure 8-3. Range ofMotion for Flexion andExtension of the UpperBody Based onAnatomyNeutral(0°)Flexion (75° TO 90°)Figure 8-4. Placing aTowel Beneath the LowerSpine can Help Achieve theRight Form for AbdominalExercisesExtension (30°)Because of limited flexibility, it is betterTowelto start abdominal exercises at approximately15° of extension and eventually work toward30° extension. A towel is particularly useful because you can adjust it to provide inclinesof 15° and 30° .Recommendations for Sit-UpsIn recent years, the sit-up technique has undergone many modifications. Becausesit-ups compose a large portion of the SEAL training program, some specific commentsregarding their proper use are crucial.When performing sit-ups, the preferred technique is to bend the legs at the hips (at45°) with the feet flat on the deck shoulder width apart. Legs should be slightly abducted(turned outward). If hands are placed behind the head, care should be taken not to force theThe Navy SEAL Physical Fitness Guide 139