BASE PHASE · 16 WEEKS OUT

UNBOUND GRAVEL — 16 WEEKS OUT

Aerobic foundation. High volume, low intensity. Don't skip this. Built around the 320km / 2,800m profile of the Unbound in USA.

320 km·2,800 m climbing·12-20 hours·June

THE FOCUS RIGHT NOW

BUILD THE ENGINE.

Sixteen weeks out, your job is volume. Forget intervals. Forget Strava. Build the aerobic engine that every later phase sits on top of. 80% of your time should be in Zone 2 — conversational pace, nose-breathing territory. If your base phase feels easy, you're doing it right.

THIS WEEK'S ANCHOR SESSION

THE LONG Z2 RIDE

One 3-4 hour steady Zone 2 ride per week. Flat to rolling route. Cadence 85-95rpm. Heart rate below first ventilatory threshold the whole way. This is where your mitochondrial density grows.

THE WEEK

A TYPICAL WEEK, 16 WEEKS OUT

Monday

REST OR 45MIN Z1

Recovery day — coffee spin only if you want to.

Tuesday

90MIN Z2 ENDURANCE

Steady, controlled, aerobic.

Wednesday

1H STRENGTH + 30MIN EASY SPIN

Squats, deadlifts, core. Builds what the bike can't.

Thursday

90MIN Z2 WITH 3X5MIN TEMPO

Intro to structured effort — don't race it.

Friday

REST

Genuine rest. The adaptations happen now.

Saturday

3-4H LONG Z2 RIDE

Anchor session. Fueled from minute 30.

Sunday

90MIN GROUP RIDE OR SOLO Z2

Social pace. No heroes allowed.

DON'T DO THIS

The #1 base-phase mistake: riding too hard on easy days. If you arrive at Saturday already tired, you'll never build the aerobic depth you need. Discipline the volume, discipline the intensity.

EVENT INTEL

WHAT THE UNBOUND ACTUALLY DEMANDS

Unbound Gravel is the world's biggest gravel event — 320km (200mi) across the Flint Hills of Kansas on rocky unpaved roads. Lottery entry, professional field mixed with amateurs, 100mi + 50mi options. Mud years and dust years both exist.

KEY CHARACTERISTICS

✓320km (200mi) flagship + 100mi + 50mi options
✓Flint Hills rocks destroy tyres, wheels, and souls
✓Mud years (historic): bike-carrying, abandonments, DNFs at 50%
✓Kansas heat: 25-35°C with no shade
✓Self-navigated (GPS) after the first 20km

COMMON MISTAKES

✕Running tyres under 40mm — Unbound shreds light tyres
✕Trying to ride from a sportive background without ultra pacing
✕Underfueling because 'it's just bikes, not running' — 12-20 hours is ultra territory

PACING

Unbound is an ultra with a drop bag. Pace at 55-60% of your 4-hour FTP as a realistic all-day ceiling. The rocks force constant micro-adjustments; you don't hold steady power like on road. Drop bag at checkpoints 2 and 3 — strategise what's in each bag before the start.

FUELLING

80-100g carbs/hour for 12+ hours. Aid stations are official but crowded — own supply between them is faster. Heat means electrolytes dominate. Solid food at checkpoints, gels + bars between. Texan rule: if you're not peeing every 2 hours you're underfuelling.

KIT

Gravel bike with 42-45mm tyres, reinforced sidewalls (Panaracer GravelKing SK+, Challenge Gravine Race, Rene Herse Stampede Pass). Tubeless mandatory. 2-3 tyre plugs + CO2 + spare tube. Mudguards optional (but essential in mud years). Hydration pack optional but helps in heat.

WANT THIS BUILT AROUND YOUR FTP?

COACHED FOR YOUR EVENT.

Not Done Yet is the coached five-pillar system built around your actual event date. Personalised TrainingPeaks plan, weekly calls, expert masterclasses. 7-day free trial.

Apply for Not Done Yet How Coaching Works

$195/month · 7-day free trial · Cancel anytime

FAQ

COMMON QUESTIONS AT 16 WEEKS OUT

Is 16 weeks enough to train for the Unbound Gravel?+

Yes, 16 weeks is a strong window. That's enough time for a full base phase, build, peak, and taper — the classical periodisation structure. 2,800m of climbing over 320km is built with sustained Z2 volume (base) + threshold work (build) in that order.

What's the hardest part of the Unbound Gravel?+

320km (200mi) flagship + 100mi + 50mi options. running tyres under 40mm — Unbound shreds light tyres — so pacing discipline is the single biggest lever most amateurs miss. Unbound is an ultra with a drop bag.

How many hours a week should I train at 16 weeks out from the Unbound Gravel?+

Aim for 8-12 hours/week if you're targeting a strong finish. The long weekend ride is the anchor (3-4 hours at late base intensities) plus 3-4 structured weekday sessions. Volume matters more than intensity at this phase.

Do I need a coach to train for the Unbound Gravel?+

You don't need a coach to finish. You do need structure. If you're new to sportives, have a target finish time, have a plateau you can't break, or have a history of peaking wrong, a coached plan pays for itself. Inside Not Done Yet the plan is built backwards from your event date — base, build, peak, taper timed to the week the Unbound Gravel runs. 7-day free trial, $195/mo.

What gearing should I run for the Unbound Gravel?+

OTHER PHASES FOR THE UNBOUND

Later phase → 12 weeks out

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