Javelina Jundred
100 miles of Sonoran desert loops in McDowell Mountain Regional Park on Halloween weekend. Five laps of rolling trail, costumes everywhere, afternoon highs in the 80s or 90s, and a cold desert night before the 30-hour cutoff.
At Javelina Jundred, plan 500 to 900 mg sodium per hour, and 900 to 1200 mg for salty sweaters through the afternoon heat on laps two and three. Dry desert air hides how much you sweat. Restock a fixed sodium dose at Javelina Jeadquarters every lap, and keep it going overnight as appetite fades.
Where The Sodium Math Bends
Schematic profile · Cramping windows tend to cluster around major climbs and the descents that follow them
55-90°F · low humidity
Climate
hot
Humidity
low
Cutoff
30 hours
10-yr avg high
80°F
10-yr avg low
56°F
Record high / low
90° / 41°F
Years with rain
0%
The Cumulative Deficit Window
Javelina looks friendly on paper: rolling trail, four aid stations a loop, and a party at the start and finish every lap. The desert is what makes it hard. Late-October highs here average in the low 80s and have reached the mid-90s on race day, with direct sun, very low humidity and almost no shade. Dry air evaporates sweat so fast that runners underestimate how much they are losing, and for most of the field the afternoon heat falls on laps two and three. Then the desert night cools sharply, appetite fades and drinking slows, and sodium intake often stops with it. The looped course is the advantage: every lap passes the same headquarters and your own drop bag, so a per-lap sodium plan is simple to run.
Key Considerations
- Plan sodium per lap. Each loop returns to Javelina Jeadquarters and your drop bag, so restock a fixed dose there rather than counting by the hour late in the race.
- Laps two and three usually fall in the afternoon heat. Aim for 700 to 1100 mg sodium per hour then, more for salty sweaters, with ice in a bandana or hat at every aid station.
- Dry desert air hides sweat. If your skin feels dry and salt is caking on your clothes, you are losing more than you think.
- Do not stop sodium when the sun sets. The night is cooler, but intake drops as appetite fades; broth and salty foods keep sodium coming when gels stop working.
Who Finishes, And How Fast
Javelina Jundred 2025 results
Men winner · 2025
Will Murray
12:10:12course record
Women winner · 2025
Tara Dower
13:31:47course record
Free Tools, Pre-Filled For Javelina
Tap any tool. We pre-load your event, climate, and sweat profile. Adjust your weight and finish target and the plan generates instantly.
Sodium plan
Per-hour sodium and fluid targets for Javelina conditions.
Carb fueling
Hourly carb targets and a fuel menu calibrated to your weight and the Javelina duration.
Heat protocol
10-14 day adaptation plan if you're racing into heat.
Hydration audit
Weigh-in test that converts a 60-minute training session into a measured sweat rate.
Caffeine timing
Pre-race dose, mid-race top-ups, and race-week taper protocol for Javelina timing.
Dig Into The Science
Sodium Calculator for Endurance Athletes (Free Tool)
Sweat sodium varies 3 to 4x across athletes. A free sodium calculator that sets an hourly target from your body, sweat history, and race-day climate.
Stop Leg Cramps: Supplement Protocol & Risk Calculator
Leg cramps have two causes: electrolyte depletion and neuromuscular fatigue. Score yours with the free calculator, then load the 5 supplements that fix both.
Potassium for Endurance Athletes: Cramps and Targets
Potassium drives muscle contraction, fluid balance, and nerve signaling. Endurance athletes lose 100 to 300 mg per hour in sweat.
Your Javelina Plan,
Built From Real Data.
Pro unlocks a per-lap sodium, fluid, and carb schedule keyed to the actual course: the opening 22.3-mile loop, the afternoon heat laps, and the overnight laps, with restock targets at Javelina Jeadquarters each time through.
- Your sweat rate, from a weigh-in test or your best estimate
- Per-leg sodium, fluid, and carb schedule keyed to the course profile
- Branded, printable PDF
- Post-race feedback capture so the next plan is sharper
Per race
Every race
Unlimited race plans today. Strava connection and the multi-event calendar are still in development.
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About Javelina
How much sodium should I take per hour at Javelina Jundred?
Most runners need 500 to 900 mg per hour, and salty sweaters 900 to 1200 mg through the afternoon heat. Needs drop overnight but do not fall to zero. Use the calculator with the hot setting and plan your doses per lap.
How hot is the Javelina Jundred?
Late-October highs in McDowell Mountain Regional Park average in the low 80s, and race days have reached the mid-90s, with very low humidity and little shade. Overnight lows average in the 50s and have dropped into the high 30s.
How is the Javelina Jundred course laid out?
One 22.3-mile loop followed by four 19.45-mile loops, each with four aid stations, for about 6,300 feet of total climbing. The longest gap between aid stations is about 6.6 miles, and every loop finishes at Javelina Jeadquarters.
How fast do runners finish the Javelina Jundred?
In 2025 Will Murray set the course record of 12:10:12 and Tara Dower set the women's record of 13:31:47. About 490 runners finished the 100 miles inside the 30-hour cutoff, and most of them ran through the night to do it.