Clinical Trial: Reduction of Risk for Low Back Injury in Theater of Operations

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Reduction of Risk for Low Back Injury in Theater of Operations

Brief Summary: The investigators will conduct a controlled clinical trial with U.S. Army soldiers training to become combat medics. The purpose of this study is to determine if a 11-week, high intensity exercise program targeting the low back muscles using specialized equipment will result in a 25% increase in low back muscular strength and endurance compared with a lower intensity general core stability exercise.

Detailed Summary:

Background Low back injury is responsible for the largest percentage of non-battle injuries in the theater of operations and is a large contributor to non-expiration of active service attrition in the US Armed Forces. Weakness and poor endurance of the back muscles are associated with low back injury. Targeted, high intensity exercise approaches using specialized equipment to develop the strength and endurance of the "weak link" muscle group (the lumbar extensors) have been shown to reduce risk for low back injury in high-risk civilian workers, but have not been widely implemented in military settings.

Objective/Hypothesis Specific Aim: In a controlled clinical trial, the investigators will assess the effectiveness of a high intensity progressive resistance exercise training program targeting the lumbar extensors to improve lumbar extensor muscular strength and endurance in US Army soldiers.

Hypothesis: A high intensity progressive resistance exercise for the lumbar extensors will result in a 25% increase in lumbar extensor muscular strength and endurance compared with control following the 11-week intervention.

Study Design A mixed methods, two-arm, controlled clinical trial with cluster randomization will be conducted. The sampling frame will be soldiers training to become combat medics from one domestic US Army base. Soldiers will be randomly assigned (by platoon) to one of two interventions - experimental or control. All participants at a given platoon will receive the same intervention and all interventions will be carried out at the US Army base, in addition to the soldiers' usual physical fitness training program. Participants randomized to the experimental group (strengthening exercise) will perform lumbar extensor muscle progressive resistance exercise us
Sponsor: University of South Florida

Current Primary Outcome: Isometric Lumbar Extension Muscular Strength at 11 Weeks [ Time Frame: 11 weeks ]

Isometric lumbar extension muscular strength (torque - Nm) as assessed by a validated physical performance test on the lumbar dynamometer


Original Primary Outcome: Change from baseline in Isometric lumbar extensor muscular strength at 12 weeks [ Time Frame: 12 weeks ]

Isometric lumbar extensor muscular strength (torque) as assessed by a validated physical performance test on the lumbar dynamometer.


Current Secondary Outcome:

  • Isometric Core Muscular Endurance at 11 Weeks [ Time Frame: 11 weeks ]
    Isometric core muscular endurance as assessed by a validated physical performance test (prone static plank test)
  • Dynamic Lumbar Extension Muscular Endurance at 11 Weeks [ Time Frame: 11 weeks ]
    Dynamic lumbar extension muscular endurance (# repetitions at 50% peak torque) as assessed by a validated physical performance test on the lumbar dynamometer


Original Secondary Outcome: Change from baseline in endurance as measured through physical performance tests at 12 weeks [ Time Frame: 12 weeks ]

Secondary measures include dynamic lumbar extension endurance, isometric trunk extension endurance, dynamic trunk extension endurance, and isometric core stability muscular endurance by validated physical performance tests.


Information By: University of South Florida

Dates:
Date Received: June 15, 2011
Date Started: June 2012
Date Completion:
Last Updated: May 22, 2015
Last Verified: May 2015