Surviving the heat means staying on top of your hydration, especially if you’re trying to stick to your exercise plan during this brutally hot summer. We’ve told you before that your freezer needs water bottles . What if I told you that those water bottles need to be frozen on their sides—and at a specific angle? It’s worth the effort, I swear.

Whether you have a long run planned in the morning or you simply want ready access to the coldest water possible to make it through this heat wave , here’s the small but mighty hack you need to optimize your chilled H20 consumption.

The only way I can get myself to go my runs during the summer is if I get out the door before 8 a.m. This means part of my nightly routine is to remember to stick a water bottle in the freezer so that’s its’s ice-cold and ready to go for my run in the morning. When I freeze my water bottle upright, I’m stuck waiting for the block of ice to melt off the bottom and chill the entire bottle.

Instead, the best way to prep your ice water is to fill it up just under halfway and then place it on its side. The trick is not to place the water bottle not entirely sideways, but at a 45 degree angle. This way, the block of ice doesn’t block the opening. When you’re ready to head out in the morning, take the bottle out of the freezer and fill the other half with water. The vertical block of ice is immediately in contact with (chilling) all the water; no waiting.

Now you’re ready to grab your frigid bottle and consider the best workouts to do when it’s this hot out . (And if you weren’t already sticking a water bottle in the freezer overnight, consider yourself doubly enlightened.)