[Stardust]

It depends on what you want to term mandatory. From the coach, he can dictate to the players that they must come to weightlifting, but he cannot say "or else". Meaning, there is no such thing as mandatory during the off-season. Want confirmation, ask your AD, I guarantee you he will tell you there is zero consequences if you do not come to weightlifting. However, it's at the discretion of the coach as to what to do with you once the season rolls around. You don't show up to his weightlifting, then you may find yourself low on the depth chart. However, if you are an outstanding player, you will play no matter your lifting commitment.