Purpose: The purpose of this test is to determine the range of motion when the back is arched from the prone position.

Equipment: Equipment needed is a flex box with a measuring scale marked in inches of centimeters. (NOTE: A yardstick taped to either the lowest row of bleachers or to a bench turned on its side can be used.)

1. Lie face down on the floor, with a partner applying pressure on the back of the thighs.
2. With fingers interlocked behind your neck, gently raise your head and shoulders as far as possible from the floor.
3. This position must be held for 3 seconds.

Scoring: The distance from the floor to the chin is measured to the nearest 1/2 inch. Record your score in the space provided below.

Trunk Trunk extension______ inches

Classification of Scores
To evaluate your score, refer to Table 6-2.