Don’t throw away those old milk jugs! They just might help you save a few dollars while you work through your weight loss program. Now, I realize you may not be the most fashionable person on the block, but you will eliminate at least one excuse for not working out.
One gallon of water weights 8.34 lbs. 
Not including the weight of the container, here’s approximately how much water you need to make some cheap homemade dumbells.
1 lb = 16 oz of water
2 lbs = 32 oz of water
3 lbs = 48 oz of water
4 lbs = 64 oz of water
5 lbs = 80 oz of water
With this basic break down, you can now create custom workout weights from old water bottles, shampoo bottles, or milk jugs.