Could gym trainings have a negative effect on the increase in running speed?

Good afternoon.

In May I ran my first half-marathon, the result was 2:01:13. In September it was 1:56:16.

1. What is the perfect running volume provided that my goal is to run a sub-1:48 half-marathon?
2. Is it necessary to include a long run in my training plan and how long should it be?

Thank you.

Oleg Sergeevich, good afternoon.

I run half-marathons regularly, my personal record is 1:52:00.

I've finished running season and plan to return to running trainings in spring (in late March or in the beginning of April). I have several questions:

1. What date should I choose for my first marathon's start considering that I plan to return to running trainings in March and let's assume that I'll start to train for a marathon since 1st April? I would like to prepare good, it doesn't mean quickly because my main goal is to run a marathon without injuries.
2. Could you give me some recommendations on training plan: frequency of trainings per week, weekly running volume? How will the weekly running mileage change every month?
3. What's number of speed trainings a week? How many long runs should I do?

Thank you.

Good afternoon.

I'm an amateur runner, not a professional but I'd like to run a half-marathon in spring. Please, tell me how many times a week I should train for?

Good day,

I’m running my first half marathon soon.

I’ve been training for nearly 4 months in the gym, mainly it is exercises for endurance.

Should I run a test half marathon one week before the race day?  

Thank you for your reply!