Lactate Clearance
165 min
High intensity
Hit the same 40/20 numbers at the end of a big ride as at the start. Two sets of 40/20s bracket three rounds of threshold, so the late efforts arrive with real fatigue in the legs.
John Cox
Coach, Contour Endurance
Lactate Clearance
165 min
High
8 / 10
Intermediate
Outdoors
The session
The workout
Written as a share of critical power, so it fits every rider. In Vekta it becomes your watts, with the W′ cost shown before you ride.
John Cox
Why this workout
The breakdown
Inside the workout
The question this session asks is simple: can you hit the same 40/20 numbers after the work as before it? Contour athletes use it before demanding events where the decisive efforts come late, after a substantial workload, whether that is fighting for position off the start of an XCO race and then holding on, or a hard finish after hours of racing.
The first set of eight 40/20s at 115–135% of CP sets the bar and gets the aerobic system firing. Three rounds of threshold follow, each opened with a thirty-second surge at 120% and then eleven and a half minutes at 92–95% of CP, and the kilojoules accumulate. Then the 40/20s come back, on tired legs, and the aim is to match the first set. As capacity grows the threshold rounds get longer.
Vekta sets every target from the rider's CP and shows the predicted W′ drain across the whole 165 minutes before it is ridden; the durability view afterwards places the second set of 40/20s on the fatigue-sliced power curve, which is the honest answer to the session's question.
One of the biggest days in a race-preparation block, once a week at most, and best outdoors where the threshold rounds can be ridden on real terrain.
Lactate Clearance
Stimulus
Intermediate
Workout level
Outdoors
Best ridden
Road,
XCO and MTB,
DISCIPLINE
The stimulus
Lactate Clearance, explained
Surge above threshold, settle just under it, and teach the body to clear the cost.
What it is
Over-under and variable-pace intervals that alternate short surges above critical power with longer segments just below it. The "under" is not recovery; it is the working part, where lactate produced in the surge is used as fuel while still riding hard.
Why it matters
Races are not steady. The ability to absorb an attack, a short climb or a crosswind surge and return to a hard pace without blowing is what separates finishing in the group from being dropped. This is the trainable version of that ability.
The surges should feel manageable and the "unders" should feel like the real work. If you are recovering during the under, it is too easy; if you cannot finish the set, the surge is too hard or too long.
These sessions map directly onto race demands and are the best way to expose whether an athlete's W′ recovers under load. The W′ balance trace after the session shows the pattern clearly: it should dip on each surge and partially recover through the under.
The session's surges and unders are written in % of CP and personalised in Vekta. The W′ preview shows whether the athlete can complete the set as written; the post-ride analysis names each surge and the recovery between them.
The Next workout
Workouts to pair with this one
Free for coaches. Test with your whole roster during the trial.