Holding back

My back is hurting. It is holding me back and slowing me down. I am not freely flowing.

Today the walk was short because of the pain.

I noticed and took a photo of the old weir, which I must have walked past many times. Only this morning I saw the iron grid in the pipe. It is keeping rocks out in heavy floods. It prevents blockages beyond repair.

The grid is keeping the big pieces back so that nothing gets stuck. 
Is that what my back is doing to me?