Any time a person observes a cluster of changes in function or a grouping of signs and symptoms like this, it's a good idea to see a medical doctor. Early diagnosis and treatment can make a difference in many conditions.
Most of the things you are describing can have a neurologic basis. Since there are symptoms above and below the belt, it's more likely the spinal cord is involved. This could be a condition called cervical myelopathy.
With aging, degenerative changes in the spine and surrounding soft tissues narrows the spinal canal. This narrowing is called stenosis. Spinal stenosis can lead to pressure on the spinal cord resulting in symptoms of cervical myelopathy. Males in their 50s do seem to be affected by this condition most often.
There are other neurologic conditions to consider. Multiple sclerosis, Lou Gehrig's disease, and rheumatoid arthritis are possibilities. There are many other neurologic conditions with similar signs and symptoms. Special tests are really needed to differentiate one from another.