To show you what not to do, each week STACK brings you a moment from the weight room or sports field gone horribly wrong.

Slacklining, if you are not familiar with it, is a sport in which bored college kids jump on a bouncy tightrope. If this is the first time you’ve heard of it and you’re anything like us, your next move will be to immediately search YouTube for fail videos. Because it sounds insane.

Unfortunately, if you do that, you’re going to be disappointed. Slacklining only happens a few feet above the ground or involves some sort of harness, so the falls aren’t nearly as spectacular as they should be. Sure, there’s the occasional groin shot, but slacklining is usually a lot tamer than it looks at first glance.

We say “usually,” because very rarely, the stars misalign and something goes horribly awry. This is one of those times.

Three lessons to be learned from this video:

1. If it wasn’t planted by God, it probably shouldn’t be anchoring a slackline.
2. Don’t be that guy next to the pool telling his friends not to get him wet. Because if you do that, there’s a 100 percent chance someone will pull you into the water or a roof will fall on your head.
3. If a contractor gives you the choice between the “good mortar” and the “affordable mortar,” ALWAYS go with the good mortar.

 Read more Fitness Fail Friday:

• What to Do When the Treadmill Takes Your Pants
• The Truth About Running on the Beach
• The Lowest Moment in High School Football History