What is the ruling on women following male trainers for fitness and nutrition, and what is the ruling on conversing with them at late hours, especially with the presence of transgressions in questions and speech?

The Islamic Law forbids conversation between a man and a woman who are not mahram (definition) to each other, except for a need that is deemed শর'عي (legally permissible), and with adherence to the regulations. This is due to the severe danger of the temptation of women. A woman conversing with a non-mahram man late at night about body parts for training, physical fitness, and nutrition is not considered a শর'عي (legally permissible) need, and it closes the door to the whispers of Satan.