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Home > Special Conditioning Programs > Trunk Extension
Trunk Extension
From: FM 7-22 October 2012
Purpose: This exercise develops strength in the low back muscles (Figure 6-54).
Starting Position: Sit in the machine, leaning slightly forward, with the back firmly against the padded lever arm. Select the appropriate weight and ensure the pin is secure in the weight stack. The hands grip the support bars using a neutral, closed-grip. The head is in a neutral position with the eyes looking straight ahead.
Cadence: SLOW
  1. Raise the upper body and continue extending the trunk, moving to the supine position.
  2. Return to the starting position.

Figure 6-54. Trunk extension
Check Points:
  • Keep the head and neck in a neutral position.
  • Exhale on count 1 and inhale on count 2.
Precautions: Do not jerk into position. Keep the hips and low back in contact with the pads throughout the exercise.

From: FM 7-22 October 2012 

  (Page last modified Feb 1, 2013) is dedicated to providing all the information you need to conduct the Army Physical Readiness Training as an individual or with a unit.  Everything you need from FM 7-22 is right here.
Chapter 1 Approach
Chapter 2 System
Chapter 3 Leadership
Chapter 4 Types of Programs
Chapter 5 Planning Considerations
Chapter 6 Special Conditioning Programs
Chapter 7 Execution of Training
Chapter 8 Preparation and Recovery
Chapter 9 Strength and Mobility Activities
Chapter 10 Endurance and Mobility Activities
Appendix A Army Physical Fitness Test
Appendix B Climbing Bars
Appendix C Posture and Body Mechanics
Appendix D Environmental Considerations
Appendix E Obstacle Negotiation
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