Blocks

Blocks: 6 Weeks to Cross

6 Weeks to Cross

A cyclocross race is forty-five to sixty minutes almost entirely above threshold: heart rate sits within a few percent of maximum from the gun and stays there lap after lap, and, judging by mountain-bike racing (no cyclocross power file has been studied), the power is a long string of short surges, most of five to thirty seconds, separated by corners, run-ups and coasting. It is not one effort — it is a hundred, on a base. That base cannot be built in six weeks, which is why the road stars enter the season the way they do: van der Poel and van Aert, by public coaching accounts (not a study), arrive in December with months of road riding, touch the cross bike two weeks before their first race, and ride endurance on the road between crosses. This block copies the shape. Weeks 1–3 sharpen what six weeks can sharpen — the start, the repeatable surge, threshold with a burst every minute, and a rehearsed race day. Weeks 4–6 race: the weekends are the intensity, mid-week is one simulation and one engine ride, and everything else is recovery.

Start this plan with your assistant

The assistant adapts these sessions to your event date, days and fitness — then drops the whole block on your calendar. One conversation, no blank calendar.

01

Arrive with an engine, sharpen the edge

A cross race sits on a threshold floor with surges on top: it asks for an engine, not a peak sprint. That engine was built on the road this summer; six weeks can only add the specific edge and keep the base alive. Chasing fitness now leaves you tired in October.

02

A hundred surges, not one effort

Cross sits above threshold heart rate for almost the whole race, with — by analogy with mountain-bike racing — short spikes on top and gaps where you are not pedalling. Train repeatability at 150–200% FTP on a threshold floor — 30/15s, bursts inside threshold, simulated laps — with some of it at a lower, forceful cadence.

03

The first thirty seconds decide the corner

In World Cup cross-country mountain-bike racing start position tracked finish position, and in the lab a 12-second all-out start made a 4-km effort faster — but only after a hard priming bout in the warm-up. Rehearse the whole sequence — clip-in, all-out twenty seconds, two minutes above threshold to hold the wheel.

04

The race is the workout

Two races a weekend already supply the intensity. Mid-week: one simulation, one road endurance ride, one short gym session every 7–10 days to keep the strength you built — and no third hard day.

Race week — weeks 4–6 (one or two races per weekend)
MonRestRest
TueHoleshot Starts or 30/15 Rønnestad (alternate weeks)Intensity
WedRace Simulation, or Road Engine if racing both daysRace Sim
Thu45–60 min easy on the cross bike: dismounts, barriers, cornersSkills
FriOpenersOpeners
SatRace — Race-Day Warm-Up before the startRace
SunRace, or Road Engine 2.5 hRace
  • —The six-week arc: weeks 1–3 sharpen with two cross-specific sessions a week (Starts, 30/15, Threshold + Bursts, Race Simulation in rotation), a skills day on the cross bike, one Road Engine ride and the gym. Weeks 4–6 race: the weekend is the intensity, mid-week is one simulation and one engine ride. Never more than three hard days a week, races included.
  • —Skills day is on the cross bike and easy: dismount and remount at walking speed until it is automatic, then at speed; barriers; corners on grass and gravel; a lap at race pace only to learn where to brake and shift. Practise technique fresh (a coaching habit, not a tested method). If you enjoy running, ten to fifteen minutes of short hill sprints fit here — keep it to short run-ups, never a running volume block.
  • —Two races on a weekend: Wednesday becomes Road Engine and Thursday stays easy; the second race is the second hard session. One race: Sunday is the Road Engine ride. The engine ride is the one that keeps the base alive through a season of forty-five-minute efforts.
  • —Strength: keep one short heavy session every 7–10 days (the In-Season Maintenance 30' session from Gym for Cyclists), Monday or Thursday, never within 48 hours of a race. Dropping the gym for eight weeks measurably loses sprint and peak power mid-season.
  • —Race day: warm up short and finish 10–15 minutes before the gun, keep the thighs actively warm on the grid (heated pads beat leg warmers), caffeine about an hour before at a modest dose. Eat the usual breakfast three hours out; nothing is needed during a race this short. Heart rate is useless for pacing in cross — it is near max from the first minute — ride by feel and by the wheel in front.
  • —Pacing: the start is all-out for the first corner, then the race is won at threshold by whoever spends the fewest matches. Save the big surges for gaps that matter — W′ spent early comes back slowly.
  • —Power-based load can under-read a cross race (running carries no watts), so when the number and your legs disagree, trust the legs, and take the recovery day after a double weekend regardless of what the number says.

The sessions

#Sprint#RaceSim
1:13:00
0.94IF
107TSS
#VO2Max#RaceSim
1:03:15
0.90IF
86TSS
#Threshold#Sprint
1:13:00
0.97IF
116TSS
#VO2Max#RaceSim
1:17:00
1.03IF
136TSS
#Endurance#Tempo
2:35:00
0.70IF
128TSS
#Threshold#Openers
1:00:00
0.79IF
63TSS
#Tempo#RaceSim
25:00
0.77IF
25TSS

Compiled from the sports-science literature on cyclocross and cross-country race demands (Carmichael et al. 2017; Hays et al. 2018; Ouvrard et al. 2015), short-interval and strength training in cyclists (Rønnestad et al. 2015, 2016, 2020; Llanos-Lagos et al. 2025), fast-start physiology and warm-up (Bailey et al. 2011; Tomaras & MacIntosh 2011; Faulkner et al. 2013), and public interviews and coaching accounts of how van der Poel, van Aert, Nys and Iserbyt structure a cross season (2019–2026). A general framework, not a personalized plan — adjust the targets to your own thresholds and schedule.