Hiking with Type 1 Diabetes: Don’t Let Your Blood Sugar Ruin the Trail

If you have Type 1 diabetes and you’ve ever hesitated before a hike — wondering if your blood sugar will tank two miles from the trailhead — this one’s for you.

Adventure and diabetes can absolutely coexist. But they require a plan. Specifically, an outdoor adventure plan that starts the night before you ever lace up your boots.

The Yosemite Wake-Up Call

A few years back, I joined a family group for what should have been one of the most memorable hikes of my life — a gradual, forested three-mile trail in Yosemite leading up to a stunning waterfall. Classic California wilderness.

Perfect day.

The night before, I took my normal dose of long-acting insulin without a second thought.

Big mistake.

About five minutes into the hike, my CGM started alarming. I was at 112, trending straight down. Then 89. Then 68. Then a stubborn 54 that refused to budge no matter how much I ate — and I ate everything.

Granola bars, trail mix, and eventually our entire group’s lunch: sandwiches, chips, all of it — gone before we even reached the waterfall.

I remember our good friend’s daughter being a good sport, saying, “It’s not a bad way to spend the day — munching and hiking!”

I still had 1.5 miles back to the trailhead. Instead of soaking in the scenery, making memories, and enjoying the company of people I love, I was head-down, shoveling food into my mouth, and turning a beautiful hike into a group lesson on life with diabetes. 

Why Exercise Tanks Your Blood Sugar

When you exercise, your muscles activate something called GLUT-4 receptors, which pull glucose out of your bloodstream and into your cells for energy — independent of insulin.

That means exercise is essentially doing insulin’s job on top of whatever insulin is already in your system. Stack a full dose of long-acting basal insulin on top of an active hike, and you’ve got a recipe for a dangerous low.

This is especially important if you:

• Take basal, or long-acting, insulin by injection

• Use an insulin pump

• Are generally insulin-sensitive

The Fix: Adjust Before You Go

The solution that changed everything for me is simple: reduce your basal insulin dose on days you plan to hike.

I normally take 10 units of Toujeo each night. On hiking days, I drop that to 8 units. For me, that reduction keeps my baseline insulin load in check so my body can respond normally to the demands of exercise without crashing.

Your number may look very different. Some people need a smaller reduction, some need a larger one, and some may not need to adjust basal at all and instead rely on extra carbohydrates. 

Important note on meals: reducing your basal may mean you need a slightly larger bolus, or mealtime insulin dose, to cover food on hiking days. Factor that into your planning.

Pump Users: Timing Matters

If you use an insulin pump, reducing your basal rate can be the right move — but when you reduce it matters just as much as how much you reduce it.

Many diabetes educators recommend lowering your basal rate 60 to 90 minutes before exercise begins, not at the start of the hike. This gives the reduction time to take effect before your GLUT-4 receptors kick into gear.

Many pumps also have a temporary basal rate or “exercise mode.” Get familiar with yours before you need it on a trail.

Pack Emergency Fuel — Every Single Time

Even with a well-dialed basal adjustment, always carry fast-acting carbohydrates on any hike longer than a mile or two.

This is non-negotiable.

Good options include:

• Glucose gel — purpose-built for correcting lows fast

• Apples and Bananas — quick, effective, and healthy eats 

• Gummy candy — lightweight and easy to eat on the move

• Granola bars or trail mix — helpful for sustained recovery after the initial correction

The rule I now follow: if I don’t have emergency food on me, I don’t go — or I turn back.

No trail is worth a dangerous low, miles from help.

For Unplanned Adventures

Sometimes a hike isn’t planned. A friend suggests a walk, a trail appears, or the afternoon just takes an unexpected turn outdoors.

In those moments, run through this quick mental checklist:

• When did I last take insulin, and how much?

• Do I have any food or glucose on me right now?

• What’s my current glucose reading — and which direction is it trending?

If any of those answers give you pause, trust your instincts. It’s okay to sit that one out, shorten the route, or fuel up before you start.

The Bottom Line

Diabetes doesn’t have to keep you off the trail. It just means you hike and adventure smarter.

Reduce your basal on active days, carry emergency carbs without exception.

Do those things, and you’re not managing a condition out there — you’re just hiking.

Your numbers are yours — what works on my trail won't map exactly to yours. Whether or not you’re a new diabetic or seasoned vet I hope this experience offers some help. 

Get out there. The waterfall is worth it.

If you have an outdoor adventure system that works for you, share it. It might be exactly what someone else needs to hear. 

Taylor Long