Mountain Biking In The Heat

As illustrated by Jeff’s recent misadventure at Syllamo, riding in extreme heat can lead to a pretty serious outcome. If Jeff hadn’t made the call for help when he did, the situation could have become tragic. Fortunately, with some planning and preventative measures, extreme heat doesn’t necessarily need to prevent us from enjoying the outdoors on our bikes.

First, some basic rules apply that should apply to *any* ride:

  • Ride with someone, if you can.
  • Tell someone where you are going. This includes signing in at the trailhead if there is a mechanism for that.
  • Set a “return” time and have the person in step one check in on you if you’re not back by then. (assumes there is cell service where you are going)
  • Bring what you need. (Details and examples below)
  • Plan your route, know the area (as best you can) and stick to the plan.
  • If you start to run into issues, turn around before you get into trouble. Better to cut a ride short than to never ride again.

Next, what can happen if you’re not prepared?

Injury and mechanical issues can occur on any ride, so here I will just focus on heat exhaustion.

According to, heat exhaustion can occur after varying amounts of exposure to high temperatures. There are two basic types of heat exhaustion: one caused by water depletion (dehydration) and one caused by salt (electrolyte) depletion. Mountain biking in extreme heat can easily lead to both conditions simultaneously, and when combined with humidity, the symptoms can develop rapidly. Here are some of the typical symptoms of heat exhaustion. If you start exhibiting these, STOP RIDING, find some shade and work on cooling off.

  • Confusion
  • Dizziness
  • Muscle cramps (indicates low electrolytes)
  • Headache
  • Nausea
  • Rapid heartbeat (that won’t return to normal whenexertionis stopped)
  • Dark colored urine (indicates dehydration)

If you or a riding partner gets to this point, here are some things you can do to recover:

  • Drink whatever fluids you have, whether it be water or electrolyte drink.
  • Remove extraneous clothing, especially if it is tight fitting. (Helmet, gloves, jersey, shoes/socks)
  • If there is water nearby, get in it or soak your jersey, and put it back on.
  • If you’re at or near the trailhead, get into an air-conditioned vehicle.
  • If none of these steps show any signs of alleviating the symptoms, call for medical help.
  • Untreated, heatexhaustioncan progress to heat stroke or even death.

Better yet, here are some steps to take to avoid getting into trouble in the first place:

  • Ride early (or late) when temps are cooler and the sun is not as direct.
  • Hydrate before the ride.
  • Carry as much fluid as you can manage, both water and electrolyte drinks.
  • Carry Hammer Nutrition Endurolyte tabs.
  • Get a backpacking water filter or water purification tablets in order to use water along the trail. (Note:The $10 filtering water bottles at Target do NOT filter out bacteria found in lakes and streams, however this one from Katadyn does.)
  • Wear non-cotton, wicking clothing. Proper wicking material will actually siphon away sweat and cool you better then going with bare skin.
  • Choose a trail where less exertion is required: something without too much climbing. Even better: lift-serviced downhill.
  • Go at a slower pace overall. This is not the day to beat your Strava score.
  • Again, if you start running into minor issues, turn around! Don’t let the issues accumulate into a real problem.

Here in the West where humidity is typically quite low, I can ride pretty comfortably up to 95 F. Above that it starts to get sketchy and I need to dial back the exertion, or ride a trail where I can stay moving fast enough to keep good air flow. Those of you in the South and East also have high humidity to deal with and all of the above prevention methods become that much more important.

The bottom line is to use your common sense. Prepare for the ride as you normally would with notification, tools, spares etc. After your basic preparation, pack as much hydration as you can carry as well as electrolyte tabs and water purification. Finally, make sure you’re dressed appropriately and take it easy. A slow ride is better than a Flight-For-Life ride! And of course, if it’s still too hot for riding even with these precautions, then head to the pool and ride the water slide.