What is the definition of a heart contraction? Is it when the heart relaxes or when it squeezes and pushes the blood from one place to another?
When it pushes the blood out.
Think about this question logically if you ever have to think about it again and are confused. If something contracts it is getting smaller and/or tighter. If the heart is squeezing and making itself smaller it is pushing blood out of it and throughout the body.