What can I do about a slowing MacBook Pro?

[justind]

I guess it's time for me to ask what can I do about a slowing MacBook Pro? Do I have to give up on it and purchase a new machine?
I cannot update OS or I would lose use of Adobe products I own.
10.11.6, Late 2011, OS X El Capitan, Processor: 2.8 GHz Intel Core i7, Memory: 8GB
It's a great machine but I'm getting the spinning rainbow more and more frequently.
I could toss a few more applications I guess but I run only a few at once.
I hope there is a cure. Thanks!

 

[maw_walker]

You can upgrade the hard disc to an SSD. I did that for my wife's 2010 MacBook pro and it speeded up, but after a couple more years she got frustrated with slowness. It will help but probably is a temporary measure. I normally buy Mac upgrade components here if you are interested: https://eshop.macsales.com