How to avoid lumbar spine injuries during resistance training. Craig Angle ME.d, ME.d, ATC, CSCS It has been estimated that 10-15% of all sporting injuries involve the spine. During athletic movements the bones, muscles, disk, and ligaments of the spine under go tremendous forces. These tissues experience shear, tensile, compression, bending, torsion, and a combination of all five forces at the same time. During resistance training these forces are extremely high in the lumbar region. This makes an athlete susceptible to lumbar spine injures during weight training. Researchers have indicated that muscle strains and ligament sprains are the result of most lumbar spine injuries during weight training. In one study as much as 75% of back injuries in Olympic weight lifters were related to muscle strains. Some researchers have indicated that muscle strains in the low back are a direct result of improper exercise loads, improper lifting techniques, and improper recovery intervals. Muscle strains in most cases are not serious injuries in the lumbar spine; however, serious injury does arise when damage occurs to the vertebral disk (e.g. ruptured disk). Most damage occurs to the vertebral disk when the spine is flexed. This is the primary reason why it is so important for athletes to have a flat back when executing such lifts as good mornings, dead lifts, rows, and sit ups. In contrast, there is also a high injury rate when the spine is maximally extended and loaded such as at the end of a dead lift. There are many mechanisms that cause injury in the low back and there are many complex structures of the lumbar spine that can be damaged. Sports scientists state that the lumbar spine structures are less likely to become injured if the spine is kept in its middle range of motion or neutral region. Therefore, strengthening and flexibility exercises for the torso and extremities should be performed with the lumbar spine in its neutral range of motion. Strength coaches should observe athletes as they execute lifts and provide instructive feed back when an athlete gets outside the neutral range of motion for the lumbar spine. For example, if an athlete places his/her feet on the floor during a bench press and has tight hip flexors, it will cause the lumbar spine to go into severe extension. As soon as the athlete lifts the bar off the rack he/she will begin to press the feet against the floor to gain leverage. The lumbar spine extension will increase further and will result in an increased compressive loading of the posterior bony elements of the spine. Long term compressive loading of the posterior bony elements of the spine can result in a multitude of injuries. Another example of bad technique is when athletes execute the squat with the spine flexed. Excessive trunk flexion during the squat increases intradisc (inside the spinal disk) pressure and tensile loads on the posterior aspect of the spinal disk. This may result in a ruptured disk. Athletes should be taught proper lifting mechanics. Athletes who avoid hyperflexion and hyperextension of the spine during lifting will significantly decrease their chances of spinal injury. Athletes who adopt neutral lumbar spine positioning strategies will also decrease their chance of injury. Proper lifting postures will allow for proper loads to be distributed over the spine and will decrease abnormal loading on lumbar spine structures. Performance of the muscles that surround the lumbar spine (i.e. core muscles) should be enhanced to improve dynamic stabilization of the spine during athletic and weight room activity. Strength coaches need to be aware of factors that contribute to lumbar spine injury. This will allow them to formulate safe training protocols and significantly reduce the chance of injury. References Durall, C. J. & Manske, R. C. Avoiding Lumbar Spine Injury During Resistance Training. Journal of Strength and Conditioning. 2005, 27(4) 64-72 |