One typical problem you can have with a heavy bag is that after a time the filling sinks to the bottom of the shell. This way, the bottom of the bag becomes very hard, the middle soft, and the top very lax.
Working out with such a bag is annoying and might be dangerous. If you hit the bottom it cracks your knuckles and wrists. If the middle the resistance is clumsy, and your gloves may slip. And, if the top, your fist sinks into bag leading to wrist pain.
How fast the filling sinks depends on the materials, you have used. Rugs and clothes are more willing to sink and getting hard. Flexible materials like foam do not sink, but if you only use it, the bag will be very light and soft. You can also purchase unique filling made for heavy punching bags, but I was not satisfied with it.
What did I do?
When I bought my bag, it was filled with clothes, and after a month the bottom of it was so hard that it was like hitting a brick wall.
I took it off, and throw it on the ground upside down, kick it here and there to soften it up. It got better, but after some usage, the bottom hardened back.
I was fed up with this “solution,” so I decided to refill the bag by using clothes and foam. The idea was that the clothes would add the hardness, and the foam would not allow the sinking.
I had a foam mattress that I used for nothing. I cut it up into small pieces, about 2×2 inches.
Then, I put a lot of foam to the bottom to avoid sinking. Since, the foam is flexible the weight of clothes above press it down, so the bottom will not be soft, but does not allow the textile to be compressed.
Then, I put one layer fabric, one layer pieces of foam until I reached the top.
During the filling, I hit the bag to the ground and press the filling to get the material everywhere. And when I reached the top, I filled the shell as much as I could to get a good shape.
The more foam you put in, the lighter and softer the bag will be, and vice versa.
This filling works well for me. I could tweak the hardness to my needs which is somewhat medium. Also, the hardness of the bag from top to bottom is almost the same providing an enjoyable workout experience.
If you have no foam, you can use other soft yet flexible materials such as styrofoam bubbles or foam peanut.
It needs time to refill your bag, but it is worth. You will not be annoyed anymore because of the uneven hardness.
To sum up
There are two solutions:
- Get off your bag and relocate and loosen up the filling by beating. But, you must do it regularly. Anyway, slapping and throwing the bag is a great workout as well.
- Or use the clothes and foam combo I recommended to fill the shell.
Do you know other methods? Share with us within the comment section below.