UK Personal Trainer/Fitness/Nutritionists Careers Advice

Howdy!
I'm currently doing a massage qualification and have found the anatomy part so interesting. I'd love to learn more, but I don't really know which way to take it.
I have also found myself more and more interested in exercise and nutrition and wonder whether to go down this route.

I would love to hear from any UK Personal Trainers or anyone in the fitness/nutrition sector with any careers stories, tips, advice, etc. Just to know if this is something that I could do as a career.

I guess my main questions are, what exactly do you do in a typical day? Is there any qualification that is considered better than others or what should I be looking for in a college course? Is there anything else I should be asking? Do you think living in a rural area limits the job opportunities in this sector? What sort of person would usually do well in this sort of job?

Sorry for all the questions, I'm just very curious and don't really know what my next step should be.
Thanks everyone :-)