If you’ve ever gone camping in the summer, you probably know this familiar struggle: sweating through your shirt at 2 PM, then shivering in your sleeping bag by 10. Big temperature swings are common outdoors, especially in deserts, forests, and at higher elevations. The trick to staying comfortable is all in how you layer.

Hiking with kids can be one of the best ways to spend time together outdoors. Fresh air, space to roam, a little adventure — it sounds great in theory. But ask any parent who’s actually done it, and they’ll tell you: the difference between a fun day and a total meltdown often comes down to what you packed.

Whether you’re trail running, hiking, biking, or just getting your steps in on a hot day, understanding your sweat rate and hydration needs can make the difference between a strong finish and a sluggish, cramp-filled trudge back to the trailhead.

We get it—you’re eager to hit the trail. The car’s parked, your shoes are laced, and the trailhead is calling. But skipping a proper warmup? That’s how you end up nursing a sore ankle or stiff lower back halfway up the first incline.

You’re planning a trip to the mountains. The photos look epic. The trail stats are manageable. But then you realize… the elevation gain is no joke. And you live in a place where “hill” means a speed bump.

So, how do you prep for altitude when you’re stuck at sea level?