Interesting!
What about ants, insects etc., who are so powerful for their size, how do they achieve their great comparable strength?
Ed
That's just this same square/cube thing going the other way. Again, as you get larger, you lose power to weight RATIO no matter what you do. Weight is proportional to volume, a cubed figure, while strength is proportional to cross section of bone and muscle, a squared figure. Double your dimensions, and you will cut your power/weight ratio in half. You'll have a facture of two which gets cubed for volume and only squared for weight i.e. you'll be eight times heavier and only four times stronger.
Think about it Sir_Ed, the same chemical engine powers that ant's muscles as powers ours, albeit a lot smaller. However, the energy per square centimeter or millimeter is the same, but it is applied to a gnat's whisker instead of to a lot more mass.