We use a lot of sandbags at my gym (crossfit center city) www.crossfitcc.com
(wfs) if you want to browse some videos of us using sandbags. In fact, I did JT (at least the first 21 and 4 of the second set) with the 50lb sandbag. Makes the 45lb barbell feel ridiculously light! You'll be shocked at the workout you can get with these bad boys. Good luck!