One of the challenges with training athletes is working around injuries. Programming is relatively easy when athletes are healthy and able to perform most exercises. However, often athletes get injured, and this may prevent them from being able to perform important basic movements like squatting, deadlifting, and derivatives of each (e.g., jump squats, trap bar jumps, Olympic lifts, etc.). It is the strength and conditioning coaches’ responsibility to still provide a training effect that transfer’s over to the playing field. This must be done while limiting exacerbation to the current injury with the exercise and load selection.
In a recent case study, Mann and colleagues (2014) evaluated the effectiveness of substituting back squats for heavy sled pulling for lower body strength training. The subject was a NCAA Division 1 quarterback who sustained 2 lumber disc herniations. The author’s comment that traditional machine-based exercises such as the leg press, leg curl and leg extension that are typically prescribed to injured athletes (in favor of squats) do not transfer to sporting movements very well. Their aim was to determine the effect of heavy sled pulling in place of squatting on speed development.
Every week for 6 weeks, the athlete pulled the sled (walking) for 8 repetition for 27.4 meters. Resistance was based on the subjects RPE where a RPE of 8 was ideal. Weight was added, or reduced if the RPE was below or above 8. Over the 6 week training period, the resistance load on the sled increased from 90 kg to 380 kg. Pre and post 40 yard dash times were recorded. The subject showed an impressive 0.26 second decrease (improvement) in 40 sprint time while the mean improvement of the entire team was a 0.20 second decrease. The subject also reported being able to throw the football with greater velocity as a result of the training program.
The results of this case study certainly support the use of progressive sled towing for improving lower body strength which appears to transfer quite well to field performance markers. The authors suggest that the improvement in sprint time was likely due to the specificity of the sled dragging movement, which forces the athlete to apply force horizontally into the ground, unlike squats, which only develop vertical force production. The acceleration phase of a sprint requires a high level of horizontal force production to overcome inertia and propel the body forward (horizontally). It would be interesting to see changes in split times (i.e., 10 yards), however these are not reported.
When dealing with athletes unable to perform movements that involved axial loading, heavy sled towing appears to be a suitable and effective alternative. It may also be worth including this in healthy athletes programs in addition to squatting.
Reference:
Mann, B; Stoner, J; and Ivey, P (2014) “THE USE OF HEAVY SLED DRAGGING TO INCREASE LOWER BODY STRENGTH AND SPEED IN A FOOTBALL PLAYER WITH LUMBAR ISSUES,”International Journal of Exercise Science: Conference Proceedings: Vol. 11: Iss. 2, Article 34.
Available at: http://digitalcommons.wku.edu/ijesab/vol11/iss2/34
