Ok ~ At L4-5 they call it a small protrusion ~ to protrude means to "jut out" so I have to assume it's a herniation. I wish they would just CALL it a herniation and let it go at that!!

The rest of that stuff means that it didn't mess with anything else by herniating
L5-S1 - you have degenerative disc disease - All that is is drying out of the discs. Everyone gets that as they age, only some of us get it earlier than others, and some of us get PAIN with it. Also, on both sides, you have foraminal narrowing. The foramen is the hole that the nerves pass thru to get to the spinal cord. Also there's no significant spinal canal narrowing.
What you should & shouldn't do depends on how much PAIN you're in. Walking is great for spinal problems. I'm not so sure I'd be jogging right now. Impact activities might be iffy too, but again that depends on your pain. Yoga is good, especially the stretches.
If you had this MRI due to pain, I think I'd cut back on the jogging/impact activities . Continue with the stretches/Yoga and ask the doc about going to physical therapy or ask what exercises you should be doing to reduce your pain.
Best of luck and i hope this heals up quickly for you. God bless. Hugs, Lee