Go back to the starting line and try to beat that mark and every new mark from then on. Straight jumps involve repeated jumps skyward. Stand with your feet shoulder width apart and try to jump as high as you can, straight up ten times in a row. For advanced athletes, touch the floor before every jump but do not break at the waist. Keep your eyes on the sky throughout the entire exercise.
Stomach Connecting the upper and lower body is the responsibility of the stomach muscles.
Strengthening your abdomen is also a great way to keep your lower back in shape. Sit-ups are the easy answer to keeping your stomach nice and strong. To begin, try crunches, which are like mini sit-ups. Lye on your back with your knees bent and your lower back flat on the floor. Contract your stomach muscles enough to bring your shoulder blades up off the floor, and hold this position for one second.