When building a workout you'll have the option to set different weights for both your male and female members. After the different weights are set, the site will only display the appropriate weight for each member. For example, if a female member logs into the site and attempts to post a result for Fran, 65# will be displayed because the site will recognize the account as a female user.
In order to set different weights, go through the workout building process. Add a movement that has a weight component and click the "vary for women" link. Enter the different weights. The first number is for the men, the second is for the women.
The description will be updated to show the varying weights.