Many injuries are caused by overuse or poor mechanics due to weakness. The latter is very common with beginner & older runners.  In my experience, a lot of poor mechanics can be corrected with strength training. However, it’s important to perform the proper exercises before you get injured. The following video reveals 3 simple exercises to strengthen glutes and hips.

Weak glutes and hips are a primary risk factor for knee & other injuries. 

These exercises can be performed at home or almost anywhere. The only special equipment required is an exercise band for the last exercise.

My recommendation is to perform these exercises regularly (2-3 sets, at least 2 times per week).  Other exercises can be completed to strengthen hamstrings and leg muscles.