Looking on the internet deeply has found these results:

a shot on your arm is the most popular phrase on the web.

a shot on the arm 1126,000 results on the web	a shot on your arm 1160,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I think this team needed a shot in the arm and my mind was the syringe. This would be a shot in the arm for worldwide work towards achieving the MDGs. Talk about a shot in the arm for the computer industry. We need a shot in the arm. Once again, the Swiss economy gets a shot in the arm. I think this team needed a shot in the arm and my mind was the syringe. Well, your partner here decided to give me a shot in the arm. And I'll tell you, MicroCon needed a shot in the arm.	I think this team needed a shot in the arm and my mind was the syringe. Once again, the Swiss economy gets a shot in the arm. We need a shot in the arm. And I'll tell you, MicroCon needed a shot in the arm. Well, your partner here decided to give me a shot in the arm. Talk about a shot in the arm for the computer industry. I could have shot off your arm. This would be a shot in the arm for worldwide work towards achieving the MDGs.

a shot on the arm

1126,000 results on the web

a shot on your arm

1160,000 results on the web

More popular!

I think this team needed a shot in the arm and my mind was the syringe.
This would be a shot in the arm for worldwide work towards achieving the MDGs.
Talk about a shot in the arm for the computer industry.
We need a shot in the arm.
Once again, the Swiss economy gets a shot in the arm.
I think this team needed a shot in the arm and my mind was the syringe.
Well, your partner here decided to give me a shot in the arm.
And I'll tell you, MicroCon needed a shot in the arm.

I think this team needed a shot in the arm and my mind was the syringe.
Once again, the Swiss economy gets a shot in the arm.
We need a shot in the arm.
And I'll tell you, MicroCon needed a shot in the arm.
Well, your partner here decided to give me a shot in the arm.
Talk about a shot in the arm for the computer industry.
I could have shot off your arm.
This would be a shot in the arm for worldwide work towards achieving the MDGs.