what is the strongest plywood….is it stronger than hardboard?

Marine plywood is about the strongest I know of that is accessible. They use a waterproof glue that is much better than reg plywood.

Strongest Plywood

If you need only 1/2 inch, use either marine ply or if it is for interior, use any hardwood plywood that has solid plies of the same or similar material. There is also a “lumber core” available but a little harder to find at your local store.

Marine ply in addition to having waterproof glue [as most exterior plywoods do] also has no “voids” which pretty well all other plywoods do. these are natural openings like knots etc that are in the unseen plies that make up the sheets. This improves the impact strength.

There is a 1/2 inch birch that is without voids that is used in the furniture making business but I am darned if I can think of the name of it!

Veneer – core plywood is the strongest plywood you can buy. What makes it so strong is the way the plies are laid down. Each ply is laid at a 90 degree angle to the one under it giving the plywood strength in all directions.

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Any of the answers stating that it doesn’t have strengthening benefits on the upper body are obviously not runners/ don’t understand the mechanics of running. Basically depending on the distance your talking about, running has a brilliant overall effect on the body. Not only will running give you good posture, but it has benefits on the abs and to an extent the upper body in general. (this all comes from a correct running action, and keeping your body upright whilst running.) Don’t get me wrong, your not going to get any bigger/ ridiculously stronger ‘up top’ running (hence runners do core exercises, such as press ups and sit ups) but it will make you stronger.

I believe any type of fitness will make you stronger if you put great effort into. I have a toner tummy and upper arms, if you’re wanting muscles you gotta use weights but I believe I’m stronger all around, body, and mind.

What is your application, ie , what are you trying to do?