I think this form of IF is better for females as well, since it is less stressful on the body. For the sake of not burning your body out too much I would say that you should still consume over 1000 calories especially if you are working out that intensely. I think it would be extremely difficult also to eat only 500 calories. Stick to nutrient dense foods and still ensure you are getting enough protein to sustain muscles used while working out.