Pulled Left Hamstring

I think I must have pulled it on Saturday because that is when I first started feeling some tightness in my legs. Yesterday it was tight but not too painful. Today I woke up and it is definitely pulled. I am hoping a few days off the bike will help. I am going to take today off and tomorrow I will do some core-work and stretching. I am hoping that it will heal quickly. My first race is only 3 weeks away and I am looking for a strong showing.