This is a 12 week primary build training plan for a 100M Ultramarathon. This assumes that you can run 50K or 5-6 hours in one go. This is an aggressive building plan that quickly escalates to longer runs, quick builds and some high intensity sessions during the week.

There are 5 run workouts each week. This plan will give you a general guideline as a final 12 week block to a 100 miler ultramarathon. There will be back to back long runs that are based on time instead of distance. Training "time on feet" better reflects the actual stress on your body when you are on the trails and helps develop foot toughness and fatigue. The adaptation for a 100-miler comes from spending long periods moving efficiently, not just chasing a mileage number.

This training plan starts with the "Build" phase and bypassess the "Base" phase. This plan assumes that you already have general fitness and aerobic capacity established. This training begins with anaerobic workouts and structured intensity. Volume will increase gradually and layer upon the base training of the previous weeks. This phase will start building long sustain efforts and race specific demands.

Strength training will be 2X-3X times a week and focus on endurance. This will prevent injury, promote fatigue resistance and improve durability. Javelina is runnable and not especially steep, so your strength work doesn't need to look like a bodybuilder program.

At week 9, the Peak Phase begins, final fitness build phase and critical training block before Taper, This will be the highest volume and training load with the most race specific fitness
Core goals are to achieve maximum race-specific physical demands and simulate race day conditions.

For Javelina specifically, many successful runners peak with long runs in the 4–6 hour range, where the goal is practicing race effort, fueling, hydration, and staying comfortable on tired legs—the exact skills you'll use during the race. Often a 50K 3-4 weeks prior to Javelina is an ideal dress rehearsal for the event.

The last 2 weeks of the training plan, before the race week, will be the taper phase. This is a planned reduction in training to allow the body to recover and absorb the training. The goal is to show up at the start line feeling refreshed and ready, not exhausted. Some may need more recovery than this, please listen to you rbody and reduce training early if you need.

Recovery and restoration is the focus for this phase. Strength training will be reduced to 2 times a week and reduced in volume, more for maintenance.

The final race week training will prepare you for your 100M ultramarathon race with low volume and high intensity.