Which word order is correct?

Hi,

Which one of the following is correct? If both are correct, which one sounds better?

"Median frequency slope per unit time for middle deltoid muscle before and after six weeks of proprioception exercises in groups 1, 2, and the control group."

"Median frequency slope of middle deltoid muscle per unit time before and after six weeks of proprioception exercises in groups 1, 2, and the control group."

Thanks!