Stingray Seen, Churchill Fins, Strong Current, Crowded Beach, Gravity, Archimedes Principle

I need to live out past the breakers, I think, to keep the pain low.  This gravity thing is messing me up.  I mean, Sir Isaac Newton in the late 1600's elucidated this phenomenon whereby the Earth continuously pulls us down toward its center at a constant rate--it never lets up.  I think that it wasn't until the early 1900's that scientists gave a number to the Earth's gravitational pull, calculated to be 9.81 meters/second squared. Since I'm not falling toward the Earth from space, but resting on Earth, the gravitational pull that I feel is 9.81 meters/second.
So, when our bodies are hurting; when we have to lean over and drag ourselves through the day; when we experience squished vertebral discs and painful hips, knees, and feet--we are feeling the cumulative effects of the Earth's center pulling on us at 9.81 m/s.  This takes a toll after some decades under this force field. Throw in some broken body parts and it gets worse.
When I'm in the ocean, I am still under the 9.81 m/s gravitational pull, but this is partially offset by the buoyancy effect of the salt water.  BUT, there is HOPE.
There was a Greek scientist named Archimedes, who in approximately 200 BC, propounded the theory that we know as Archimedes' Principle, that states that a body immersed in water is pushed up by a buoyant force.  Thank Goodness!  Archimedes' Principle is the scientific reason that I need to be in the ocean!  It states that a body is buoyed up by a force equal to the weight of the volume of water that it displaces.  (The salt in the ocean buoys you up more than fresh water.)
So, my bad gravity is offset to a fair degree by Archimedes' buoyancy, relieving my body parts from the pain that gravity inflicts on my damaged pieces. 
Yesterday (Saturday) I went to the beach at about 4 PM.  Very crowded.  Water temp 64 degrees according to the lifeguard's chalk board.  Choppy water. Choppy waves--about 1-3 feet, poor shape.  Good water for beachgoers to frolic in the water.
I parked about six blocks away (free) and did my slow walk first with my camera to take pictures.  I looked like I was on the Bataan Death March.  (No disrespect to those heroes intended).
I got my photos, walked back up to the car, and walked back down to swim.  I had decided to wear my Churchill's because I thought that the exercise on my low back might put it back into place--it didn't.
"Will he ever get to the swim," they ask.  Okay.  Out I go with a thin swim cap for visibility and fins.  I'm on the north side of the pier, tower #4, at Surfrider Way.  The water is not 64--more like 74 in some spots.  Some spots maybe 64 for brief periods.  I went around the pier and to just outside the surf zone at tower #3 on the south side of the pier.  I'm at 30 minutes;  I had been taking it easy.
I turned around to do a round-trip.  The ocean was completely different.  High tide was about 7:40 PM, so the tide was coming in and it was hard to swim out against it.  So I swim against it with the intention of angling out to the end of the pier, like the hypotenuse of a right triangle--the pier and the shoreline being the straight lines of this triangle.  I'm swimming out and I get out past the end of the pier by about 30 yards, but, I am not near the pier--I am actually straight out from tower #3.
I had encountered a very strong current running south, along with the incoming tide. 
But I felt good.  No low back pain!  Plenty of energy and air in my lungs, good goggles, relaxed, far away from people, and confident that I would kick around the pier with my trusty fins.
So I swam and swam, and swam and swam;  I would look ahead to the pier and it never really got much closer.  A boat cruised by.  I picked up my effort to advance on the pier and I made progress slowly.  It was a good half hour or more that I swam hard and eventually got past the pier.  What a current!  The water was pretty clean and I saw a small stingray swim by me several feet below me.  That was the only sea life that I saw on that swim.
I was running out of gas on my way in on the north side but had a very good workout.  My neck hurt in the water--but it always does when I breathe to the right.  Then, what happens?
I get to the sand to try to stand up and get out of there and my low back starts to kill me!  Thank you Archimedes and damn you Isaac Newton!  My total swim was 1 hour and 41 minutes!  That current was something else! 
I did a slow-motion walk back to the car and eased into the driver's seat.  When I got home I took a fistfull of pills to stop the pain.  In spite of the pain, it was a GREAT day in the water.

"The first time you quit is the last time you try."