Q:

Does exercises other than running help in improving the distance or speed of running? 

I can normally do a 10 kilometer in one hour, but when I try hard, I can do it in 50 minutes. 
Can exercises like swimming, push-ups and other body weight exercises, doing exercise with an ab roller, doing ball Jackknife, and Ball Ab Rollout, help me in improving my running speed or increasing distance? 
I tried to increase my running distance to more than 10k and here's what happened. 
I was thinking of increasing my speed as well as distance of run (normally it is 10 km) so after a break of two weeks (I had some work so i had to take break from running) I ran for about 14 kilometers and it caused pain in my left knee.  I went to a physiotherapist, he gave me some kind of ultrasonic massage, and now I am fine. 

A:

Yeah you should rarely, if ever, plan on adding more than 10% in either distance or speed per week as a general rule. 
More to the point of your question is whether you want to increase aerobic speed (how fast can you run 10k) or burst speed (how fast can you run < 1k). 
If the latter, then yes, bodyweight exercises like squats, one-legged squats, box jumps, dead lifts (maybe with slightly more than body weight), etc can definitely help.  Running stairs, hills, and/or intervals will also help here. 
If you want to increase aerobic speed then those same exercises can help, but not nearly as much as building your aerobic base.  There are lots of theories on base building, but the basis of most of them is a lot of steady mileage below your anaerobic threshold.  A good way of determining this is your max heart rate (usually 180-200) minus your age.  This keeps you much more in fat-burning mode than sugar/glycogen burning mode. 
If you train at this level, you will eventually (60 days?  90 days?)  notice that you can run for the same amount of time and a faster pace at the same heart rate.  This is because you will have increased your ability to convert fat to fuel.  This will increase your 10k speed, as well as increase the distance you can run at the same pace. 
Note: If you train at a given heart rate for a given duration, it will mostly likely result in having to slow down, sometimes significantly, for a while as most of us run with a higher than mostly aerobic heart rate.  But over time, your long-distance speed will increase. 

A:

Exercises that require increased cardiovascular activity should all help improve stamina, and exercises that require explosive muscle movements should all help improve power, acceleration and speed.   For instance, swimming is a great total-body exercise that can improve both.   It's worthwhile to note, however, that other exercises probably can't help you improve things that might be specific to running, such as your stride, posture, breathing rhythms, etc. 
A type of training I recommend you look into is High-Intensity Interval Training.   Studies have shown it to have numerous benefits.   For instance, if you go for long, slower jogs of great distance, you will improve endurance but not speed.   Strangely, the opposite is not true: if you do a series of fast bursts of sprinting to exhaustion, then resting, then sprinting again, etc.,  you will improve both speed AND endurance, and in much shorter workouts than long runs. 
http://www.sciencedaily.com/releases/2010/03/100311123639.htm

