4 FOR THE CORE, EXERCISE 4: QUADRAPLEX
The starting position is on the hands and knees with the back flat. Contract the abdominal muscles as described in the bent-leg raise. Without rotating the trunk or sagging or arching the spine, straighten the left leg to the rear and the right arm to the front. Hold for at least 5 seconds, recover to the starting position if needed, then return to the quadraplex. The goal is to hold each quadraplex position (left and right) for 60 seconds each. Alternate the arm and leg movements on subsequent repetitions, repeating for one minute. The key to this exercise is controlled lowering and raising of the opposite arm and leg while keeping the rest of the body aligned and still (Figure 6-9).
Figure 6-9. Quadraplex