Going to the gym can become an idol. But so can not going to the gym. Watching football can become an idol. But so can not watching football.
If we receive all things as a gift from God, and give them back to Him in worship, they are good things.
But as soon as we place them before God in our hearts, we become idolaters.
On the flip side of that coin, if we puff ourselves up with pride for abstaining from any particular thing or activity, we make ourselves our own idol.
Both are bad. Both are idolatry. We can honor the Lord by participating or abstaining from these amoral things, or we can dishonor him by doing the same. Our heart’s posture shows who or what we are worshiping.
One way or another, these activities are worshipful.