I've been weight training on & off (but mostly on) for the past 12 years. I really enjoy it! Since I injured myself triathlon training in March, it's just about the only kind of physical activity I can do without aggravating the injury, so I've been into it more lately.
My strategy the last several months is to do low weight & high rep training. Specifically, I've been doing two sets of 12 - 20 reps. If I can't lift the weight at least 24 times... to hell with it. At 40, it's time to increase the resistance. It's not worth risking injury, and it's not worth the potential of becoming super bulky and VERY un-femme lifting heavier weights.
Without hormones, (I'm not TS, and don't foresee that changing any time soon.) you're kind of caught in a trap. When you hit the gym hard with a man's body, it's going to become more masculine. All that said, I was wondering how many of the other ladies are into weight training and if so, maybe you could share your experiences about hitting the gym hard and still looking femme.