Upcomming wintertraining / Starting with Gym-workouts?

[the_taaboo]

Hi there,

I am going to start my winter/basic training mid of November, until then I go for a ride when I want to and the weather is fine. Running is also part of this phase.
Last season I reached again the same power/weight level as last year. In light of the same time schedule as last year I will increase the intervall parts of the bike training. My question is:
Should I also go to a Gym in the next weeks for individual leg muscle training (In easy words: getting a little more diameter on the upper leg...) and if yes what kind of training should I prefere?

Thanks
Taaboo