When exercising the muscles in one's back, it is important, in order to maintain a healthy back, to exercise the musc...

Nakia on September 15, 2019

Generally healthy back

Are you saying that a generally healthy back is not a sufficient condition? If so, then I am not understanding the premise. Please break down the premise.

2 Replies

on November 22, 2019

I am also having trouble understanding the video explanation for this question, how would it be diagrammed?

Shunhe on December 21 at 01:12AM

Hi all,

Let's call "maintaining a healthy back" MHB, "balanced muscle development" BMD, and "exercising muscles on opposite sides of the spine equally" EMOSSE. We know that MHB - > BMD (balanced muscle development is needed to a healthy back, so if you have a healthy back, you have balanced muscle development). We also have the conclusion, which is MHB - > EMOSSE.

Now take a look at (B), which states that "if not EMOSSE, then not BMD." The contrapositive of this is BMD - > EMOSSE, and if this is true, then MHB - > BMD - > EMOSSE, and if this is the case, then MHB - > EMOSSE, which is the conclusion we're looking for.

Hope that helps,let me know if you have any questions.