Training Readiness

Training readiness is a composite daily metric that integrates multiple physiological signals — primarily heart rate variability (HRV), resting heart rate (RHR), and sleep quality — into a single score indicating how well-recovered your body is and how capable it is of absorbing hard training on a given day. A high readiness score suggests the body can productively handle high-intensity work; a low readiness score indicates that recovery should take priority over performance.

Deeper Explanation

Training adaptation is not determined solely by the stress imposed during workouts — it is equally determined by the quality of recovery between them. A hard session performed on a fully recovered body produces a strong adaptation signal. The same session performed in a fatigued state produces a blunted adaptation with greater risk of injury, illness, and accumulating overreaching.

Training readiness attempts to quantify recovery state objectively, transforming subjective feelings of "I feel okay" or "I feel tired" into data-driven guidance. The underlying physiology is autonomic nervous system function: a well-recovered body shows high parasympathetic tone (reflected in elevated HRV, lower resting HR, and consolidated sleep), while a fatigued body shows sympathetic activation (suppressed HRV, elevated RHR, fragmented sleep).

Components of a readiness score:

HRV (Heart Rate Variability) — typically 45–55% of the total score: The most sensitive recovery indicator. Morning RMSSD is compared to a rolling 7-day and 30-day personal baseline. A reading more than 15–20% below the 7-day average suppresses the readiness score significantly. A single low reading is weighted less than a trend of multiple low readings.

Resting Heart Rate (RHR) — typically 10–20% of the total score: Compared to personal morning RHR baseline. An elevation of 5+ bpm above normal indicates sympathetic activation. RHR is a slower-responding metric than HRV — a sustained elevation over multiple days is more meaningful than a single elevated reading.

Sleep Quality and Duration — typically 30–40% of the total score: Adequate sleep is the most important non-training determinant of recovery. Both total sleep duration and sleep quality (sleep continuity, time in deep/REM sleep if measurable) contribute. Sleeping less than 6.5 hours or having highly fragmented sleep significantly reduces the readiness score.

Interpreting readiness scores:

• 75–100: High readiness. Parasympathetic dominant, well-recovered. Pursue planned high-intensity sessions without modification.
• 50–74: Moderate readiness. Body is partially recovered. Aerobic and moderate-intensity sessions appropriate; consider reducing or skipping high-intensity elements.
• Below 50: Low readiness. Significant recovery deficit. Prioritize rest, sleep, and nutrition. High-intensity training on this day produces minimal adaptation and high fatigue cost.

What suppresses readiness:

• Hard training (especially cumulative load over days)
• Poor sleep (duration and/or quality)
• Alcohol consumption (even 2–3 drinks suppress HRV for 12–24 hours)
• Illness or immune activation
• Significant psychological stress
• Travel and jet lag
• Heat stress and dehydration
• Caloric deficit or under-fueling

How Training Readiness Relates to Training

Guided intensity adjustment: HRV-guided training — where athletes adjust intensity based on daily readiness rather than following a rigid calendar — has been shown in randomized controlled trials to produce superior VO2 max improvements compared to fixed-schedule training with equivalent total volume. The mechanism: hard sessions performed on high-readiness days generate a stronger training stimulus than the same sessions performed on low-readiness days.

Overtraining prevention: A chronically low readiness score (below 50 for 5+ consecutive days) is a reliable early indicator of functional overreaching — often appearing before subjective fatigue symptoms emerge. Early identification allows training volume reduction before performance begins to decline.

Periodization feedback: Readiness data provides real-time feedback on whether a training block's load is appropriate. If readiness scores trend upward during a build block, the training is being absorbed. If scores trend downward continuously without recovery days, the load exceeds recovery capacity.

How Fitiv Uses Training Readiness

Fitiv Pulse generates a daily readiness score after each morning HRV measurement, combining HRV trend, resting heart rate, and sleep score into a 0–100 result.

Fitiv's readiness score weighting:

• HRV trend: approximately 50%
• Sleep score (duration + quality): approximately 35%
• Resting heart rate deviation: approximately 15%

The readiness score is displayed prominently on the Fitiv home screen each morning after the measurement session. Alongside the score, Fitiv provides a plain-language training recommendation — "Go hard today," "Stick to aerobic work," or "Focus on recovery" — removing the need for athletes to interpret the underlying metrics themselves.

Readiness integrated with training load: Fitiv connects readiness scores to the CTL/ATL training load model. An athlete with a TSB (Training Stress Balance) of −20 (moderate fatigue) and a readiness score of 70 receives different guidance than an athlete with TSB of −20 and a readiness score of 45 — because the latter has physiological recovery debt while the former is merely carrying normal training stress. This integration of subjective recovery markers with objective load data provides more precise training guidance than either signal alone.

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Frequently Asked Questions

Q: Why does my readiness score vary so much from day to day? A: HRV — the primary component of most readiness scores — is acutely sensitive to lifestyle factors that change daily: sleep quality, alcohol, stress, food timing, and cumulative training load. A 15–20% swing in RMSSD between consecutive mornings is within the normal range for many athletes. For this reason, Fitiv weights the readiness score toward the 7-day HRV trend rather than reacting heavily to a single day's reading. If your score varies dramatically without obvious causes, inconsistent measurement conditions (different wake time, sitting vs. lying down, post-coffee measurement) may be introducing noise.

Q: My readiness score is low but I feel fine subjectively — should I train hard? A: Trust the data more than you might expect. Subjective feelings of readiness are notoriously inaccurate — particularly in athletes who are chronically slightly fatigued but have adapted their perceived effort baseline to match. That said, context matters. An important competition or a single high-priority session can override a yellow readiness score. A red score (below 50) for multiple consecutive days is harder to dismiss — the physiological data is reflecting a real recovery deficit even if you feel functional.

Q: Can I improve my readiness score? A: Yes — by improving the inputs. The most impactful interventions are: increasing sleep duration by 30–60 minutes per night, reducing training load, eliminating or reducing alcohol, managing psychological stress, and ensuring adequate carbohydrate and caloric intake. Fitiv's 30-day readiness trend helps you identify which behavioral changes most reliably improve your scores, since effects are visible within 5–7 days of consistent changes.