Yes it is important but it is not end all and be all of life. It certain not as important and math/english/science etc..
I won't ever force my kids to extra co curricular sports. They are active kids and we have huge yard so I don't see it as a big deal.
I once had a huge fight with the sports teacher at school over dd. She had Ross river, glandular and bama Forrest fevers all in 3 months, She was recovering for 6 months. She was hardly eating so I made the decision that she wasn't to do any sports for the rest of that year on the advice of her dr's. The sports teacher thought that it was a cope out as she was able to stand and walk around etc...
I simply told her that if she had to miss sports so that she can attend the rest of school than so be it. She still didn't agree so i just pulled the I am mother so get over it card.