Concerning the tired and unproven assertion of Calvin bowling on the Lord's Day, see this:
http://www.naphtali.com/pdf/calvinbw.pdf
Also available here in blog article form. If Calvin did indeed bowl on the Lord's day, it doesn't inform us as to what he believed, it simply means he was a hypocrite because what he believed on such matters is clear from his sermons on Deuteronomy.
-----Added 12/3/2008 at 06:22:15 EST-----
Since this comes up fairly regularly I have pasted this from this other thread where it has come up most recently. There is a tale that Calvin played a game, a sports, pastime if you will on the Lord's day. It is a old story. The above traces it through much of the anti Sabbatarian literature back to the time of the Westminster Assembly (interestingly enough). It makes for interesting reading I think even if the author is indeed long winded (and he is).