The Value of Sandbag Training

By Mark Roozen

 The following information was put out by Jason C. Brown off the IYCA  website.  They were looking at the difference between Kettlebells vs Dumbells.  Another avenue to exam is, what is the difference between Kettlebells vs Sandbags.   Jason talks about that some of the questions he gets are:

1.        "What's the difference between and kettlebell and a dumbbell?"

2.        "Will kettlebell training carry-over into my activities of daily living more than training with dumbbells?"

He goes on to explain that there is a distinct mechanical difference between a kettlebell and a dumbbell based on law of levers.   So my question would be, what is the mechanical difference between the kettlebell and sandbags from the law of levers and also from how to maneuver and adjust to the shift of movement and awkward weight.

Since kettlebells possess what is called Extended Moment Arm of Resistance, sandbags would could be classified under the same category.  What this means is that both forms of training will have the implements center of gravity outside the grip or palm.  Brown goes into explaining that dumbbells do not possess this and have a center of gravity that is fixed or static, always within your grip or palm.  We understand that a shorter Moment Arm of Resistance (shortening the lever) makes a movement easier; choking up on a baseball bat is a great example of creating a shorter Moment Arm of Resistance.   Brown explains that technically a dumbbell swing should be easier than a kettlebell swing, but with a different size sandbags – and force moving farther away, we could then say that the kettlebell is easier than the sandbag.

Jason Brown finishes with talking about how objects that you deal with in everyday life have both an Extended Moment Arm of Resistance and a Variable Moment Arm of Resistance. Suitcases, backpacks, children, grocery bags, and six packs all share a center of gravity that lies outside your grip...just like a kettlebell.  What he doesn’t mention is that the kettlebell, like the dumbbell, is a solid mass with the weight distributed in a center mass.  The dumbbell and kettlebell’s center of mass doesn’t shift or move when being used.  So in terms of items like a backpack, children and items shifting in a grocery bag, the sandbag training would be much more "Functional." In Mr. Brown’s own words, “Make sense?” 

To me it does – it makes sense to use sandbags in your training if you are looking to work with extended moment arm resistance, variable moment arm of resistance, and working with shifting mass of an object – like we deal with in life, in movement and in sport!