Well, Dizzy,
For starters, I can assure you it was nowhere near 315 – especially towards the end of my workout.
And be careful using words like “isolate.”
You’re liable to start 10 new threads on the “isolation/one-muscle” debate.
But you are feeling the work in the right place.
Second, this really isn’t the kind of movement you try for singles or doubles, and I believe that using that kind of weight could be dangerous, considering the body’s position.
Weight is not as important as form here, and 10-12 reps is usually what I aim for.
If you do this exercise as recommended, you’re starting with the weight on the safety stops. Adds a different feel from most bb chest presses, which often begin with a negative portion rep.
I honestly don’t know how big a role - if any - this fact plays in the movement (every other rep will in essence be starting from the top range anyway).
But if you want to handle more weight, I suppose you could – after adjusting the bar & bench to the appropriate positions – start your set with the bar at the top rather than the bottom portion of the rep. It will be easier to get started.
I also recommend doing these near the end of your workout when your body is thoroughly warmed up and limber.
I did stop doing these for a period because they began bothering my right shoulder a bit.
