Video summary

Cyclometry podcast #12

Main summary

Key takeaways

Educational

Main ideas, concepts, and lessons

1) Why cyclometry / the “cyclometry” framework exists

  • The podcast idea is to answer common (and some less-common) questions about cycling training using cyclometry.
  • Cyclometry is presented as a way to map an athlete’s functional capabilities into power thresholds (e.g., GPU/CPU/AVC/SVC and glycolysis-related terms), then use those to:
    • design training
    • interpret results
  • The speaker emphasizes the model’s goal is to reduce confusion caused by internet myths and improve understanding of training impact and progression.

2) Nutrition, glycogen, and why energy restriction can disrupt hard intervals

  • Hard interval work requires sufficient fuel availability.
  • Key claim:
    • Training “in reduced energy status” (low glycogen/glucose availability)—especially doing intervals without glycogen reserves—can “do more harm than good.”
  • If someone is dieting (or on a restrictive regimen):
    • interval work should be reduced or adapted, because the body can’t fully express the intended metabolic work.
  • Breaking a diet/regimen too aggressively can cause:
    • endocrine disruption over ~1–2 weeks
    • overtraining effects
    • loss of form

3) Order and structure of sessions/blocks: what should come last

  • Concept: hardest work is often most effective when placed later in a block (“last job” / “most severe last”).
  • Example given:
    • swapping higher-level workloads so that the most demanding work (e.g., very high intensity / sprint-like work) comes after foundational work, allowing better recruitment of high-threshold motor units with fatigue managed appropriately.

4) Sprint / high-threshold inclusion (and why it’s placed at the end)

  • The podcast argues sprint work and high power accelerations should be done toward the end of sessions to help recruit the highest-threshold units despite fatigue.
  • Rough guideline mentioned:
    • sprint intensity depends on body weight (example threshold figures referenced, e.g., ~5-second power targets and weight-dependent assumptions).

Methodology: cyclometry testing (the “four-parameter” structure)

The guest describes testing to estimate cyclometry parameters (GPU/CPU and related thresholds). The model uses four parameters, so it relies on a sequence of tests designed to “solve the equations” as best as possible.

Testing sequence (as described)

  1. 30-second maximum test

    • Purpose: assess maximum glycolytic capacity (SVC/GPU context is mentioned).
    • Main criterion: athlete must stay near/above estimated glycolytic capacity through the 30 seconds.
    • If the athlete “fails” the test:
      • the capacity estimate is considered unreliable/definitely wrong (described as a “guaranteed fence/accuracy warning”).

  2. 2-minute interval test

    • Purpose: determine the glycolysis-related split between phases/thresholds (GPU vs CPU region).
    • It provides partial information about where aerobic vs anaerobic glycolysis sits.

  3. 8–12 minute test (time not fixed; power selected)

    • Purpose: resembles a “Cooper-like” treadmill concept (translated idea).
    • Method:
      • choose a slightly higher power target (about ~15% above an estimate)
      • work smoothly at that power as long as possible
      • if power is too high (fail CPU / overstep into GPU), the result becomes inaccurate because glycolysis is “spent from the wrong side” too early
    • Time window guidance:
      • ending too early (near 8 minutes) increases error (too much influence from extremes)
      • extending too long (near 12 minutes) increases mathematical error
    • If accuracy is poor:
      • repeat by adjusting power and re-run.

  4. 18–20 minute test

    • Purpose: confirm/consolidate CPU-related capacity.
    • If the first three tests are done correctly, this is largely confirmation.
    • Margin of error:
      • measurement error and device limitations (roughly referenced).

Measurement/practical caveats mentioned

  • Cyclometry is applied using mathematical reconstruction from test results.
  • The speaker warns about relying on power-meters/ergometers that might “lie” (miscalibrate).
  • Tests should follow a consistent template.
  • “Best test” is argued to be the competitive discipline/format closest to the athlete’s race.

Model definitions and interpretations (power thresholds)

Parameters named

  • GPU: “power / total capacity of glycolysis” (watts).
  • CPU: power of the second phase of glycolysis (aerobic glycolysis is referenced; the zone between CPU and GPU is emphasized).
  • AVC / SVC
    • represent maximum “work” levels in the relevant zone
    • interpreted as capacities/buffers enabling high power above aerobic threshold until glycolysis buffers/limits are depleted

Key formula idea (as stated)

  • The difference between GPU and CPU is emphasized as a meaningful construct (conceptually expressed as “GPU minus CPU” area/transition).

Biological metaphor used

  • The guest uses a chemical-reactor analogy:
    • the body is not a single uniform reaction
    • glycolysis happens in “many simultaneous reaction places”
  • “Compensation” occurs when delivery improves (blood flow, gradients, temperature, oxygen delivery), so performance may exceed simple “paper” estimates.

Methodology: “Compensated power” vs FTP-styled constant-power thinking

A major portion argues that:

  • real cycling performance deviates from static FTP-like assumptions due to metabolic compensation
  • two protocols that produce the same average FTP can yield different outcomes depending on:
    • how power ramps/peaks
    • how glycolysis buffers discharge and recover during the effort

The claim about compensation

  • Example comparison:
    • a 20-minute flat target vs a declining/ramped variation
  • The “compensated” protocol may yield a different effective CPU/glycolysis usage pattern.
  • This is used to criticize purely FTP-based training math for certain interval structures, especially when intensities cross GPU/CPU boundaries.

Training principles and progression

1) Training intensity “ceilings” and buffer effects

  • HIIT / high-intensity interval training is portrayed as rapidly improving:
    • buffer-related thresholds (AVC/SVC) for early responders
  • Eventually, growth hits a ceiling:
    • after initial gains, progress becomes slower and can stall if training is too extreme or not periodized.

2) Time-in-zone matters; not just load level

  • The stress stimulus is described as depending more on total time under load than on nominal load level.
  • Example analog (from squats):
    • load impact can differ based on distribution (e.g., fewer reps at higher weight vs more reps at same weight)
    • the speaker emphasizes total work / “physics/math” rather than comfort-based feeling.

3) Block periodization length (the “4-week” claim)

  • For the guest’s coaching style:
    • 4-week blocks are described as optimal for healthy typical athletes.
  • Alternatives:
    • 1-week blocks are “crooked” (likely insufficient)
    • 5-week blocks are often too much for most, especially with high intensity
  • If fewer weeks:
    • under-received developmental impulse
  • Winter/off-season can differ due to recovery needs.

4) Progress tracking and testing

  • Tests are often described as unnecessary because:
    • you can observe AVC/SVC/CPU behavior in training platform outputs and forecasts.
  • Progress metric approach:
    • tracking via screenshots of programs/apps and athlete diaries
    • judging progress by trends across weeks, not single sessions
  • Testing is described as “an art”:
    • inconsistent testing formats create inconsistent results
    • use the test format closest to competition when possible

5) Risk management against “suicidal” intensity

  • Repeated warning:
    • don’t schedule workouts that require dying/100% to the last repetition every time.
  • Consequences:
    • you lose gains after weeks (endocrine fatigue over ~1 month)
    • long-term performance drops
  • Rule-like guidance:
    • “Ideal” work is suggested to be around ~95% of maximum cumulative work capacity that you can digest
    • repeatedly going higher (dying with the last of your strength) harms sustainability

6) “Race before the race” concept

  • Avoid peak-race efforts too early in preparation.
  • If an athlete sees “form is rising,” they might push hard before the real peak:
    • fatigue accumulates
    • the coach loses control over taper/peak timing
  • Recommended logic:
    • trust the coach’s timing
    • rest/unload so form consolidates naturally, then execute in the right window

7) VO2/CPU intervals volume ranges

  • For many amateurs:
    • VO2 zone weekly time is discussed in ranges (e.g., ~40–60 min/week early, potentially higher with progress)
  • For more advanced levels:
    • weekly time increases further, potentially to ~12–16 hours/week total training
  • The podcast mixes intensity zone discussions within overall training volume.

Training nutrition / recovery and conditioning

  • Unload weeks (“rest periods”) are supported via block structure:
    • reduce hours/time under load while keeping some rhythm
  • Recovery considerations include:
    • glycogen availability
    • dehydration/joint stress on long rides
    • musculoskeletal micro-breaks from long high-power efforts

Recommended reading / media (books and authors mentioned)

The guest shares top “vectors/books,” emphasizing physiology and Soviet training methodology.

Named works include:

  • V. Verkhoshansky
    • recommended; methodology emphasized
  • Yuri Siluyanov / Siluyanov
    • referred to as the “yellow book,” plus related co-authors/development materials
  • “Crocodile”
    • described as a mind/mental-facing book connected to a cyclist’s internal reflections
    • written in the Soviet Union by a journalist
    • about a multi-day race—likely Tour de France-themed even if renamed in the text
  • Universal sports physiology textbook
    • university-level physiology of energy processes

Also referenced historically:

  • hints of ATP/energy concept discussions (e.g., “ATP and and all that,” with exact attribution not fully clear)
  • high-level endurance literature and Soviet classics are contrasted against internet “tinsel”

Speakers / sources featured

  1. Roman Byzov
    • guest speaker; primary speaker for cyclometry/testing/training methodology
  2. Seryoga Tsvetkov
    • host mentioned as driving the conversation/returned later for emotion/transition (details in this summary are mostly about Roman)
  3. V. N. Verkhoshansky
  4. Dr. Yuri Siluyanov / Siluyanov
  5. Andrew Coggan / Hunter Allen
    • named in connection with FTP/TrainingPeaks history
  6. WKO / TrainingPeaks
  7. Skiba / W’ balance mention
    • references to W’ / SKIBovskaya in critique of FTP-style math
  8. Dima Merzlikin / Merzlitena / “Merzlikina”
    • unclear exact spelling; referenced as an example athlete
  9. Cyclometry-related platform tools
    • Android/Web graphs/tools mentioned; no single clearly named company/source

Original video