The one arm one leg pushup is an exercise in total body tension.
Strength has a greater purpose.
If you think you are only strong if you can lift a certain number, whatever that number is, you will feel pretty weak most of the time. Strength is not a data point; it’s not a number. It’s an attitude.
The Kettlebell is an Ancient Russian Weapon Against Weakness.
If you are wondering what ‘strong’ is, it is probably not you.