Mike's Bike Shop cycling club:
Increase strenght/diet issues

I have been biking (road bike) for just over 2 months and have been averaging 4 days a weeks about 20-25 miles per day.  My average speed normally ranges from 12.5 up to 14.0 (depending on how many hills I run into).  My biggest challenge are tackling those steep inclines, I find myself with not enough leg strenght to maintain speeds above 10 mph most times.  Once over those hills, I find myself laboring for a bit before I can get back up to normal speeds.  Should I be incorporating strenght training to build up my leg muscel or can I do need to increase my distance to help with this issue?

 I've lost about 10 pounds since beginning  seriously riding and know my diet or lack of it is the reason why I have not lost more.  How strict of a diet should I consider if I want to loose another 5-10 lbs?