Endurance athletes face unique hydration challenges when riding through extreme temperatures—from blistering heat to freezing cold. HydraPak athletes Kait Boyle and Kurt Refsnider know this firsthand, having raced in conditions ranging from -40°F to over 100°F. In this blog, they share their hydration strategies, gear preferences, and key tips for staying fueled and hydrated during ultra-endurance cycling events. Whether you're tackling a one-day mountain bike race or a multi-day gravel adventure, their advice will help you conquer the elements and keep pedaling strong.
As professional cyclists on the Industry Nine - Pivot Pro Backcountry Team, Kait and Kurt have raced in some of the most extreme events across the globe, constantly fine-tuning their hydration strategies. Recently, Kait finished an impressive 4th at the 24-Hour World Championships in Australia, crediting her hydration and nutrition plan for helping her power through challenging conditions. In this post, they break down six different hydration approaches from their recent races, each with its own set of challenges—from high-altitude races with no resupply points to multi-day rides through freezing winter conditions. Each section offers practical takeaways on how to adjust hydration based on the length, temperature, and intensity of the ride.
Kait's Hydration Game Plan
White Rim, Solo MTB Time Trial
- Location: Canyonlands National Park, UT
- Distance/Duration: 100 miles, ~7.5 hours
- Bike Type: Pivot Mach 4SL XC full suspension
- Water resupply/aid stations: Self-supported, no caching of water, no water available along route.
- Weather: Low of upper 30s at pre-dawn start, high in low 60s, overcast and breezy.
- Hydration gear: Contour 2L bladder in running vest, Stow 500mL in jersey pocket, Breakaway 20oz bottle.
- Strategy & considerations: With cool temps, I carried just over 3L of water and started well-hydrated. The only possible refill spot is early on, so it wasn’t worth stopping—everything had to be carried from the start. Staying hydrated while managing weight was key to my success.
24-Hour World Championships
- Location: Mount Stromlo Forest Park, Canberra, Australia
- Distance/Duration: Solo 24h mountain bike lap race, 6.5 mi lap for 24 hours
- Bike Type: Pivot Mach 4SL XC full suspension
- Water resupply/aid stations: Supported - I could change bikes and get anything I needed in the pit area at the beginning/end of every lap, which was every 35-60 minutes depending on lap times
- Weather: Highs in upper 60s, lows in upper 30s.
- Hydration gear: Breakaway 20oz bottles - 6 bottles at the pit to have a variety of drink options (GU Roctane, electrolytes, plain water), but I carried one bottle at a time.
- Strategy & considerations: My crew filled my bottles to match my lap times as I didn’t need a full bottle for such a short lap, and I swapped bottles every lap. At night, I got a warm drink mix in my bottles to keep me warm!
Kurt's Hydration Game Plan
Fat Pursuit - Winter Fat Bike Ultra
- Location: Island Park, ID
- Distance/Duration: 200km, 20+ hours
- Bike Type: Pivot LES Fat fat bike
- Water resupply/aid stations: Aid stations every 6-8+ hours
- Weather: Very wintery - windy with an overnight low of -40F!
- Hydration gear: Contour 3L reservoir + Breakaway Insulated 24oz bottle
- Strategy & considerations: The biggest challenge in winter ultras is keeping fluids accessible while preventing them from freezing. I wore my hydration pack under all my insulating layers, and I ran the hose inside my clothes to keep it from freezing. Despite my efforts, the mouthpiece still froze up at -40°F! Keeping fluids drinkable in these conditions is a constant battle.
Havasu Havoc MTB marathon + 2-day ride to race
- Location: Lake Havasu, AZ
- Event Type: Marathon MTB + bikepack
- Distance/Duration: 3-hour race (40 miles) + 2 full days bikepacking (170 miles)
- Bike Type: Pivot Mach 4SL XC full suspension
- Water resupply/aid stations: Water sources 8-10 hours apart bikepacking; carried all fluids for race
- Weather: Daytime highs around 90F and ~50 at the start line
- Hydration gear: Stow 1L soft bottle + Seeker+ 3L with filter cap + Flux 1L soft bottle + Contour 2L reservoir
- Strategy & considerations: During this training adventure I took on a 170-mile bikepacking ride from Prescott to the race, followed by the 40-mile MTB marathon the next day. It was winter, but the desert still hit the 90s, so I carried almost 2 gallons of water. My setup included a Seeker+ 3L with a filter in my frame bag, a Contour 2L and a soft bottle in my backpack, plus an extra soft bottle of orange juice for dry camping. For the race, I relied on the Contour 2L in a running vest and the Flux soft bottle in my frame bag, which kept me hydrated for 3 hours and helped secure the win.
Kurt & Kait's Team Hydration
Downieville Classic All Mountain Race
- Location: Lost Sierra, CA
- Event Type: Point to point cross country and downhill mountain bike race, 2 days, both raced on the same bike, same set up.
- Distance/Duration: Day 1: 30 miles, ~2.5 hours; Day 2, 16 mile downhill, ~50 minutes
- Bike Type: Pivot Mach 4SL XC full suspension
- Water resupply/aid stations: There are aid stations but with out handups, we chose to skip them and carry what we needed for the race.
- Weather: 105+ degrees!
- Hydration gear: Day 1: Velocity Insulated 1.5L reservoir + Breakaway 20oz - ice in both at start! Day 2: Just a 1/2-full 20oz Breakaway to drink on the one climb mid-descent.
- Strategy & considerations: With extreme heat, we calculated around 24oz of fluid per hour. We started with ice in both our bottles and reservoirs to keep the water cool longer, and planned on carrying enough to skip the aid stations and stay hydrated on our own terms.
Unbound Gravel XL
- Location: Emporia, KS
- Event Type: Gravel Ultra
- Distance/Duration: 350 miles, ~23-27 hours
- Bike Type: Pivot Vault gravel bike
- Water resupply/aid stations: Gas stations/town parks every 4-6 hours
- Weather: Daytime highs in the mid-80s and overnight lows around 60
- Hydration gear: 2x 30oz Breakaway bottles + Contour 2L reservoir in a Patagonia Slope Runner vest
- Strategy & considerations: The XL is an interesting one from a hydration/carrying capacity strategy perspective - carry more at a time and you don't need to stop as frequently to fill up from gas stations or town parks along the route, or carry less, be lighter, and stop more frequently. We both opted for an intermediate strategy of carrying close to 4L of water away from ~3 stops over the ~24-hour race and adding pre-measured bags of Gu Roctane drink mix to our bottles/reservoirs (Kurt also opted for filling a bottle with Coke at a couple gas stations). Had conditions been warmer, we likely would have carried an additional couple liters of capacity via a Seeker in a frame bag.
Quick Tips for Hydration
- Hot Weather: Aim for 24oz of water per hour and start with ice in your bottles.
- Cold Weather: Keep your hydration system close to your body and blow air back into the hose to prevent freezing.
- Long Races: Carry more to stop less, but balance weight and water needs based on the course.
- Insulation Matters: Use insulated reservoirs and bottles to maintain the temperature of your fluids for longer.
Whether you're battling triple-digit heat or braving sub-zero temperatures, proper hydration can make or break your endurance effort. From insulating your water supply to carrying enough for extended periods, the strategies Kait and Kurt have shared show how important it is to plan ahead. Remember, staying hydrated isn’t just about performance—it’s about survival in extreme conditions. Make hydration a priority on every ride, and you’ll go further, faster, and safer.
