Weight training is fine, but heavy weight training might not be. Just like a little whiskey is fine but a lot may not be. Moderation is key.
They’re talking “girl heavy”.
As in 200lb leg presses...after working up to it.
Define “heavy”
Heavy is a relative term depending on your strength. What’s heavy when you start may seem light after a year of training. Certainly one should not “ego lift” - lifting too much for your current strength. It is the most common error in the gym - for novice and experienced lifters alike.