Javelina Jundred Race Strategy: Lap Splits for Every Finish Goal¶
You leave Jeadquarters for lap 2 feeling like you managed lap 1 well. The sun is up now, low and warm, not the midday desert you have been warned about. You ran the first 22 miles the way you planned. Your legs feel fine. That is the part the Javelina Jundred doesn't advertise in its pre-race briefing: whatever happened on lap 1 won't tell you the full story until you are somewhere in lap 2, then lap 3, and the arithmetic has already been running without you.
The 5-loop structure is what makes this particular. The course isn't hard on the body in unusual ways. It doesn't have Hope Pass or the Twin Lakes climb. What it has is 100 miles of genuinely runnable trail, roughly 63 feet of gain per mile, and a course geometry that gives lap 1 runners unlimited rope. There is nothing mechanical on this course forcing you to slow down when you are going too fast. The feedback arrives later, in the heat, with 60 miles still in front of you.
This post is the arithmetic done in advance. The goal is a concrete lap target for your finish window, and a clear picture of which laps will overlap with the desert heat, so you can set lap 1 on purpose rather than find out what you committed to somewhere around mile 42.
The course in numbers¶
The Javelina Jundred runs on a modified Pemberton Trail loop in McDowell Mountain Regional Park, starting and finishing at Jeadquarters in Fountain Hills, Arizona. The race starts at 6:00 AM on October 31, with a 30-hour cutoff at noon on November 1. Runners depart in the dark: sunrise in Fountain Hills on October 31 is approximately 6:28 AM.
| Lap | Distance | Cumulative miles | Notes |
|---|---|---|---|
| Lap 1 (opener) | 22.3 mi | 22.3 mi | Slightly longer route from Jeadquarters |
| Lap 2 | 19.4 mi | 41.7 mi | Identical loop |
| Lap 3 | 19.4 mi | 61.1 mi | Identical loop |
| Lap 4 | 19.4 mi | 80.5 mi | Identical loop |
| Lap 5 | 19.4 mi | 99.9 mi | Total per Aravaipa: 100.1 mi |
Total elevation gain: 6,296 ft across 100.1 miles, per Aravaipa's official course data. That works out to roughly 63 feet of gain per mile. For comparison, Leadville averages closer to 106 feet per mile across its course, with Hope Pass alone climbing 3,600 feet across two crossings. Javelina's climbs are real and cumulative, but no single section punishes you the way a mountain 100 does.
That relative flatness is the course's defining characteristic for pacing. On a mountain 100, the climbs do some of the work of pace regulation for you. At Javelina, they don't. A runner who goes out 20 minutes faster than they should on lap 1 has nothing mechanical pushing back on that decision until the body decides to do the pushing. The trail feels honest. It just doesn't tell you what lap 1 cost until you need those minutes on lap 3.
The heat window¶
Fountain Hills sits at roughly 1,500 feet in the Sonoran Desert, about 25 miles east-northeast of Phoenix. On October 31, temperatures typically climb from the mid-50s at the 6:00 AM start to the mid-to-upper 70s by early afternoon. Desert sun at that elevation is more intense than the ambient temperature suggests, particularly in the first half of the day when runners are still fresh enough not to notice it mattering.
The meaningful heat window on October 31 runs from roughly 9:00 AM to 5:00 PM, with peak temperatures and full sun exposure between 11 AM and 3 PM. Temperatures drop back toward the 60s once the sun sets. Sunset on October 31 in Fountain Hills is approximately 5:44 PM: Arizona does not observe daylight saving time, so there is no clock change complicating your planning.
That window is approximately eight hours long. Every runner targeting a finish under 30 hours will spend at least one full lap inside it. Most will spend two. A 22-hour runner is back in the heat for a significant stretch of lap 3. A 24-hour runner runs all of lap 2 and a large portion of lap 3 in it. The heat window is a structural feature of this race, not an edge case. Knowing exactly which laps land inside it is the first step to doing something useful about it.
Why lap 1 is a commitment, not a buffer¶
The widely understood idea in 100-mile racing is that going out too fast on lap 1 will cost you later. What is less understood for a course like Javelina is the specific shape of how it costs you.
Muscular fatigue and early glycogen depletion from an overcooked lap 1 typically surface around miles 35 to 50. On a mountain course, those miles often involve a long climb that naturally regulates your pace anyway. At Javelina, miles 35 to 50 fall squarely inside lap 2 and the early miles of lap 3, which are also inside the heat window, also on a flat-to-rolling course that will not force you to slow down on its own. There is no climb to blame and no terrain to point to. You just feel slower than you should.
The compounding problem is what happens to later lap times. Running lap 1 twenty minutes faster than your target doesn't save twenty minutes for later. It shifts the degradation curve forward. Runners who over-pace lap 1 routinely find that laps 2 and 3 together run 40 to 80 minutes slower than their target, while they still feel like they are managing the situation. The math surfaces at lap 4 and lap 5, when there is nothing left to do about it. This pattern appears consistently across Javelina race reports and results from multiple years: the damage is real, it is reproducible, and it is not obvious while it is happening.
Race results and reports from Javelina's recent history suggest that most DNFs cluster in laps 2 and 3. That is the heat window. That is the post-lap-1 accumulation period. For many runners, it is also the first stretch of time they have ever spent moving at pace in temperatures warmer than any training run they did in September. Race data from 2025 suggests roughly half the field did not finish. The DNF distribution does not spread evenly across the five laps. It peaks where the heat and the lap 1 commitment converge.
The lap target tables¶
The two tables below give the arithmetic. Two things to keep in mind before reading them: first, these are even-effort targets, meaning constant average pace across all miles. Real laps will slow toward the end; real lap 1s should be intentionally slower than these numbers. Second, these are lap times without aid station time built in. Add 3 to 8 minutes per stop to get your on-course math right.
Even-effort lap times by finish goal¶
The average pace for each finish goal is total minutes divided by 100.1 miles. Lap 1 is 22.3 miles; laps 2 through 5 are each 19.4 miles.
| Finish goal | Lap 1 target | Laps 2-5 target (each) | Avg pace |
|---|---|---|---|
| 22 hours | ~4h 55min | ~4h 16min | ~13:11/mi |
| 24 hours | ~5h 21min | ~4h 39min | ~14:23/mi |
| 26 hours | ~5h 48min | ~5h 02min | ~15:35/mi |
| 28 hours | ~6h 14min | ~5h 26min | ~16:47/mi |
Clock times with heat window overlay¶
Clock times build from the 6:00 AM start using the lap targets above. The heat window runs approximately 9:00 AM to 5:00 PM. Sunset is around 5:44 PM.
| Finish goal | Lap 1 done | Lap 2 (start to end) | Lap 3 (start to end) | First fully dark lap |
|---|---|---|---|---|
| 22 hours | 10:55 AM | 10:55 AM to 3:11 PM [heat] | 3:11 PM to 7:27 PM [heat, then dark] | Lap 4 |
| 24 hours | 11:21 AM | 11:21 AM to 4:00 PM [heat] | 4:00 PM to 8:39 PM [heat, then dark] | Lap 4 |
| 26 hours | 11:48 AM | 11:48 AM to 4:50 PM [heat] | 4:50 PM to 9:52 PM [heat, then dark] | Lap 4 |
| 28 hours | 12:14 PM | 12:14 PM to 5:40 PM [heat] | 5:40 PM to 11:06 PM [dark] | Lap 3 |
The column worth reading carefully is lap 3. For every finish goal in the 22-to-26-hour range, lap 3 starts inside the heat window and ends after dark. That is a lap that begins when accumulated fatigue is first becoming expensive, runs through the hottest remaining hours of the day, and transitions into night. For 28-hour runners, lap 3 starts right at sunset and runs through the first hours of darkness with the heat accumulation of laps 1 and 2 already in the legs.
In every scenario in this table, lap 2 falls entirely inside the heat window. That is not a planning failure. It is the course geometry. The question is how much of lap 3 also happens in the heat, and the answer to that question is set by how fast lap 1 was.
Setting lap 1 on purpose¶
The tables above are a baseline, not a plan. They represent equal effort across every mile, which is the mathematical floor. Building a real race plan means putting a buffer into lap 1, not hoping to manufacture it somewhere later.
A working rule: target lap 1 at 10 to 15 minutes slower than the even-effort table shows. If the table says your lap 1 target is 5:21 for a 24-hour finish, plan to leave Jeadquarters after lap 1 in 5:30 to 5:35. That buffer should be built into the start, not something you try to create in the back half of the lap when you notice the pace feels good.
The reason this is hard is that lap 1 at Javelina feels easy. The miles are rolling and well-marked. The field is fresh and moving together at 6:00 AM. The sensation of managing yourself is not reliable feedback on this course, because the feedback the course provides is delayed by design. What is reliable: arriving at each aid station and checking whether you are ahead of your table target. If the answer is yes by more than five minutes, you are going too fast.
The heat laps demand more from aid stations. Plan for 5 to 8 minutes at Jeadquarters on laps 2 and 3 rather than the 3-minute quick stop you might execute on lap 1. Ice, fluids, a moment to wet down, a calorie check before leaving. That time is already in the budget if lap 1 went according to the intentional plan. If lap 1 was too fast, you will feel the pull to skip those minutes on laps 2 and 3. That is the wrong trade.
The simple if/then: if you come through lap 1 ahead of your target, spend the extra minutes at Jeadquarters before going out on lap 2. Eat, cool down, then go. The heat is coming regardless of what happened on lap 1.
Aid station anchor points¶
The Pemberton Trail loop has four main aid station locations that repeat on every lap. The approximate positions below are drawn from race reports and results across multiple Javelina years. Verify names, positions, and current-year specifics at aravaipa.run before October 31.
Jackass Junction (approximately 6 miles into each lap from Jeadquarters): The first stop after leaving the main station. If you arrive here more than 10 minutes ahead of your target split, slow down before the back half of the lap. The surplus doesn't disappear on its own.
Coyote Camp (approximately 10 to 11 miles, near the midpoint of the loop): The turnaround of the out-and-back section in the middle of the course. This is the most useful clock check on the course. If your split to Coyote Camp on lap 2 matches your split from lap 1, you are running even effort. If it is faster, you are accumulating a debt that lap 3 will collect.
Rattlesnake Ranch (approximately 15 miles into each lap): The last station before returning to Jeadquarters. On laps 2 and 3, this stop falls in the heat of the day for most runners. This is where ice and electrolytes matter most. Don't rush through it to make up time. The time it costs to cool down here is less than the time a heat spiral costs on the back three miles to Jeadquarters.
Javelina Jeadquarters (start/finish of each lap): The main station with crew access. Your crew is here every 19 to 22 miles. That support is a genuine asset and also a psychological variable. Every Jeadquarters stop includes a moment where stopping sounds more reasonable than continuing. Have a pre-race conversation with your crew about what "I want to sit down" sounds like versus "I need to stop." Those are different situations, and the crew needs to know the difference before the race starts.
What your training data already knows¶
The tables give the structure. What they cannot give you is the right number for your lap 1 slot. That comes from what your training log shows about your actual sustainable pace on long efforts, and what happens to that pace in the back half when the first half pushed.
You are in peak training right now. The long runs you have completed or will finish in the next three weeks are the dataset. The question to ask of them is not what pace you ran. It is this: on efforts where you pushed the first half, what did the second half look like? And on efforts where you held back early, how much did the back half cost? That ratio is the most honest input you have for setting lap 1 on October 31.
If your runs are syncing from Strava or Apple Health, the picture is already there at navrun.app. The time-on-feet data across your recent long efforts is what maps most honestly onto what lap 2 will cost after a fast lap 1. Not pace. Not miles. Hours of continuous movement, and how pace holds across them.
See you at Jeadquarters on October 31.