If you want to gain muscle, it's ok to hire a female personal trainer. From a professional point of view, female coaches are no worse than male coaches. If you are a novice, you should focus on exercising large muscle groups, namely chest, back, buttocks and legs. Women's fitness mainly focuses on hips, legs and back, especially hips and legs, so female coaches will have unique experience and insights in this regard. This is one of the benefits of personal education. I can chat with you during training to relieve boredom, so that fitness is not so boring, and the coach is very comfortable to help you stretch after training.