Yes! You can!.
"Why should you do that? ". In - specialized kinesiology - we muscle test and while muscle testing one can project and influence. Just to ... experiment, .... make a point, ... project something to show how things can be differently.
S/he who doesn't play with the possiblities is not open to the facts of life!
"Doesn't make this the muscle test unreliable?". No, it is just your proof. Is proves you, you should be open minded and blanc in mind whenever you perform this kind of testing or else you will not involve the possiblities that are involved.
Any investigator should and shall be "open minded" and that is true for all kinds of investigation. Don't you agree!