Stocky, not muscled. Her age, combined with what must be fat, especially without any definition of the muscles to be seen, suggest she lacks any sort of strength or dexterity. Furthermore, she has chosen the pseudonym of 'White', a colour often associated with purity and innocence. Though it could be a clever double bluff, I sincerely doubt it.

[He shrugs and leans over the board to gather up the location cards.]

Now, location. We can whittle down our remaining suspects by determining where they were at the time of the murder, which can easily be determined by examining the temperature of the body and the coagulation of any visible blood.