Recently I have been working on a story that features a pop star who is actually an alien super soldier raised by human parents. That is to say, she was genetically engineered to be a biological killing machine, but turned out instead to be a pop sensation thanks to her good looks, heightened learning ability, and enhanced creativity (Among other things).
I imagine her to be physically proportioned like Taylor Swift, or Rihanna or [insert other female celebrity icon]. So she is not particularly well-muscled, at least not visibly so.
Could genetic engineering dramatically increase the strength of a person without visually affecting their outward appearance?
Specifically is increased strength by a factor of 10 feasible, given gene-editting, without a visual increase in size? (It is alright if it requires increased density and thus weight, or various hidden structural changes)
Also, if not a factor of 10, then what lower numerical value would make sense? (x2, x4, x5, x8?) Could it be higher? I am aware that Superman level strength is probably impossible given physics, but what is the limit of organic muscle given the cross-sectional size of the average human arm?
I would like to stick to hard-science, but given that genetic engineering is in its infancy, I understand some things are speculative.
The following are additional thoughts and ideas that come to mind related to the topic. They are possible future questions, but not the main question of this post.
I have read in several places, that chimps, despite being smaller than humans, are pound for pound stronger than us. Sometimes this is chalked up to no restraint as a chimp can fly into a primal fury much more easily than a modern human. But other times this is actually spoken about as physiological difference in the structure of the muscles between the two species. Could muscle design produce the pop star super soldier I am envisioning?
Another note is that in researching artificial muscles, I came across experiments in using spider silk to produce muscles that performed many times better than the fibers present in human muscles. Now they did not recreate an entire arm or anything, but they did do tests lifting small weights and comparing the values human muscles fibers are known to be able to manage. Could a super soldier be designed, through hard-science genetic engineering, to possess muscles made from other organic materials and end up visually no different than a normal human, but physically much stronger? I know this can obviously happen in fiction, but I am asking is this something that science could actually accomplish in theory.
When it comes to genetic engineering, I tend to think of things that are in nature already, and the idea that if they can exist on other animals, then it is within the realm of physics to add them to humans. I understand there may be a trade off, but I am more asking if it is possible rather than what are the consequences the individual would have to live with, so long as they are not horribly impaired or anything.
The character is an "alien" but mostly in the foreign sense, biologically the character is very human aside genetic alterations to the genome to accomplish desired results. Imagine human being the template, then edits take place to create the alien.