Four Days Diablo takes place on Apr 21 – 24, 2027 in Walnut Creek, United States. The main route is 49.9 km.
- Date
- Apr 21 – 24, 2027
- Start
- Walnut Creek 🇺🇸
- Distance
- 49.9 km
- Level
- Open to all
Your 28-week plan to Four Days Diablo
The Base phase starts this week. Built around your fitness and adjusted every day as your form changes; attach the course and it prepares for the climbs too.
Build my planFree to start · No credit card
Four Days Diablo is a four-day guided wilderness camping and hiking trip traversing the 31-mile Diablo Trail across regional parks and preserves around Mount Diablo from Walnut Creek to Livermore.
What this race demands
Four Days Diablo demands four consecutive days of endurance hiking to cover a 31-mile wilderness route while carrying camping gear.
Multi-Day Endurance
Spanning four days of continuous movement, athletes must manage cumulative fatigue and recover effectively each evening in camp.
Trail Hiking Capacity
Traversing regional parks and preserves requires the structural durability and lower-body strength to sustain hours of daily walking over uneven terrain.
A multi-day hiking effort lasting several hours daily requires consistent carbohydrate intake of 30 to 60 grams per hour to sustain energy levels.
Your road to race day
Race day at Four Days Diablo is 28 weeks away. This is how a coach divides that time. The first phase starts now.
01Base16 weeks · Oct 8, 2026 – Jan 27, 2027
Aerobic foundation: mostly steady endurance work that grows the aerobic engine and the durability the later phases stand on.
02Build6 weeks · Jan 28, 2027 – Mar 10, 2027
Progressive overload: training load climbs in waves, with harder weeks stacked on the base and planned recovery weeks that let the gains land.
03Peak3 weeks · Mar 11, 2027 – Mar 31, 2027
The hardest weeks of the plan: race-specific intensity at nearly full training load, sharpening exactly what this race asks for.
04Taper2 weeks · Apr 1, 2027 – Apr 14, 2027
Volume drops while intensity stays: short, sharp efforts keep the legs awake as fatigue drains away.
05Race week1 week · Apr 15, 2027 – Apr 21, 2027
Openers, rest and logistics. The work is done; the job now is arriving fresh.
Frequently asked questions
When is Four Days Diablo?
Four Days Diablo takes place on Apr 21 – 24, 2027 in Walnut Creek, United States.
How long is Four Days Diablo?
The main route is 49.9 km.
What does Four Days Diablo demand?
Four Days Diablo demands four consecutive days of endurance hiking to cover a 31-mile wilderness route while carrying camping gear.
Who is Four Days Diablo for?
Four Days Diablo is open to all participants.
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