How to Keep an Altitude Training Log That Actually Improves Your Performance

An altitude training log is one of the most underutilized tools in a serious athlete's arsenal. Every elite program logs training. But altitude camps introduce physiological variables—acclimatization status, SpO2 fluctuations, sleep disruption, iron dynamics—that standard training logs never capture. Without tracking these variables, you are flying blind through a complex physiological process.

A well-kept altitude training log transforms your camp from a black box into a feedback system. It shows you when you are adapting, when you are overdoing it, and what worked well enough to repeat next season. This guide covers exactly what to track, how to interpret what you find, and how to use your log to make smarter decisions.

Why Standard Training Logs Fall Short at Altitude

A typical training log captures workouts, paces, distances, and maybe RPE (rate of perceived exertion). At sea level, this is usually enough to track progression and fatigue.

At altitude, the same workout performed at day 2 versus day 14 of a camp is physiologically different. SpO2 may have improved by 3–4%. Resting heart rate may have dropped 8 bpm. Lactate at a fixed pace may be 1.0 mmol/L lower. These are meaningful changes that a standard log does not capture—and without capturing them, you cannot know whether you are adapting or grinding yourself into overreaching.

Altitude training logs need to track the physiological context, not just the workout content.

The Core Components of an Altitude Training Log

1. Daily Physiology Markers

These should be captured first thing every morning, before any activity:

Blood oxygen saturation (SpO2)

• Measure with a pulse oximeter within 5 minutes of waking, before getting out of bed
• Record the value and the time
• Why it matters: SpO2 on waking is your best daily indicator of acclimatization progress. Values should trend upward across the camp as ventilatory acclimatization proceeds.
• Red flag: SpO2 consistently below 90% at rest warrants medical review and possible training load reduction

Resting heart rate (RHR)

• Measure before standing, after 5 quiet minutes
• Record the value
• Why it matters: RHR is elevated on arrival at altitude (often 5–15 bpm above sea-level baseline) and should return toward baseline as acclimatization progresses. Sustained elevation or unexpected spikes can signal illness, overtraining, or inadequate recovery.

Body weight

• Weigh every morning, naked, after urination, before eating
• Record the value
• Why it matters: Rapid weight loss (>0.5 kg/day) at altitude often reflects dehydration, insufficient caloric intake, or both. Body weight trend across the camp is also a useful proxy for energy balance.

Perceived sleep quality

• Rate on a 1–5 or 1–10 scale
• Optional: note whether you woke during the night, noted breathing disruptions, or used supplemental aids
• Why it matters: Sleep is severely disrupted at altitude in the first 3–7 days. Tracking recovery of sleep quality correlates with acclimatization progress and helps coaches time training intensity adjustments.

2. Wellness / Symptom Questionnaire

The Lake Louise AMS Score is a validated tool used in altitude medicine research that translates directly to athletic practice. Track daily:

A total score of 3 or above with headache present indicates AMS. This score typically peaks in days 1–3 and resolves by day 4–7 at moderate altitudes. Tracking it daily quantifies the acclimatization curve and identifies athletes who are struggling unusually.

Optionally add:

• Motivation/mood (1–5 scale)
• Muscle soreness (1–5 scale)
• Appetite (1–5 scale)

These five items, taking 60 seconds to complete, give a daily snapshot of athlete readiness.

3. Training Session Data

For each session, log:

Objective data:

• Date and session type (e.g., aerobic zone 2, threshold intervals, strength, technical)
• Duration and volume (meters, hours, kilometers)
• Intensity: heart rate (average and peak), power output, pace, or split
• Lactate values (if your program tests mid-camp)
• RPE (Borg 6–20 scale or 1–10 modified scale)

Contextual data:

• Altitude at which the session was conducted (training altitude may differ from sleeping altitude in LHTL protocols)
• Time of day
• Weather conditions (heat, cold, wind) — altitude weather is variable and affects performance
• Pre-session SpO2 (informative for correlating altitude with session quality)

4. Nutrition and Hydration Notes

A brief daily record:

• Fluid intake (liters)
• Notable dietary iron sources (useful for ensuring iron requirements are met)
• Supplement intake (iron, vitamin C, acetazolamide, melatonin, etc.)
• Any gastrointestinal issues

You don't need to count every calorie, but noting whether intake felt adequate versus suppressed helps identify days where underfeeding may have contributed to poor recovery.

HRV Tracking: The Most Predictive Single Metric

Heart rate variability (HRV) has become the gold standard daily readiness metric among serious endurance athletes, and it is particularly valuable at altitude where the physiological stress environment is unusually complex.

HRV at altitude:

• Typically suppresses in the first 3–7 days (acute altitude stress)
• Recovers progressively as acclimatization proceeds
• Remains a useful relative marker: day-to-day HRV changes from your personal baseline predict recovery status even when absolute values have shifted due to altitude

Apps like HRV4Training, Elite HRV, or Whoop all calculate daily HRV from 1–2 minute morning measurements. Log the absolute value (rMSSD) as well as the app's training recommendation.

Practical rule: If HRV falls more than 10% below your recent rolling 7-day average AND two or more wellness markers are also below average, that day warrants downgraded training load. This combination is more reliable than any single metric.

Tracking Acclimatization Progress: The Trend Lines Matter

The value of an altitude training log lies not in individual data points, but in trends across the camp. Some useful patterns to watch:

SpO2 recovery curve: Most athletes see resting SpO2 drop on day 1 (expected), stabilize by day 3–5, and gradually recover toward higher values by week 2. If your SpO2 is still declining or flat-lining by day 7, it is a signal to investigate: are you training too hard? Is there an underlying illness? Is the altitude too aggressive?

Lactate at fixed workload: If your program tests lactate during camp (highly recommended for serious programs), track lactate at a fixed submaximal workload across the camp. This "acclimatization drift test" shows whether the aerobic system is adapting. Declining lactate at fixed workload is one of the clearest signals that the camp is working.

RHR normalization: Track how many days it takes for your resting heart rate to return within 5 bpm of your sea-level baseline. This is a simple acclimatization benchmark. Average athletes at 2,000–2,200 m: 7–12 days. Well-trained athletes: 5–8 days. If RHR hasn't normalized by day 14, revisit training load.

Session RPE drift: Across a camp with constant training load, RPE at fixed workloads should decrease as acclimatization improves. If RPE is flat or increasing after week 2, you may be accumulating fatigue rather than adapting.

Reviewing Your Log: Pre-Camp, During Camp, Post-Camp

Pre-Camp Baseline

Before arriving at altitude, log 7–14 days of baseline morning physiology: SpO2, RHR, HRV, body weight. This gives you a personal reference point. Without a sea-level baseline, you cannot meaningfully interpret altitude values.

During Camp: Weekly Reviews

Every 5–7 days, review the log as a coaching document:

• Is SpO2 trending upward?
• Is RHR trending toward baseline?
• Are wellness scores improving?
• Is training quality (RPE at fixed load) improving or degrading?

If multiple markers are not recovering on schedule, reduce training load and extend the acclimatization phase before returning to hard efforts.

Post-Camp: What to Carry Forward

After returning to sea level, log the first 2–4 weeks as carefully as the altitude camp itself. Key markers to track:

• Performance benchmarks at sea level (compare to pre-camp baseline)
• Time-to-performance peak (most athletes peak 2–4 weeks post-camp)
• Hemoglobin or hematocrit values if your program does blood testing

This post-camp log is your evidence base for the ROI of the altitude investment. Over multiple camps, you accumulate personal data on when you peak, how long gains last, and what camp structure works best for your physiology.

Tools and Formats

Digital Options

Training Peaks: The de facto standard for serious endurance athletes. Supports HRV imports from third-party apps, TSS/CTL/ATL calculations, and detailed session data. Add custom fields for SpO2, wellness scores, and altitude.

Notion or Google Sheets: For athletes who prefer flexibility, a custom spreadsheet with daily physiology tabs, session logs, and a trend visualization layer works well. Less automated, more configurable.

Garmin Connect / Apple Health: Good for automated capture of HRV, RHR, SpO2 (if using Garmin Fenix/Forerunner with pulse ox, or Apple Watch Series 6+). Limited in customization for altitude-specific data entry.

Paper logbook: For athletes at camps without reliable technology access, a paper log is entirely adequate. The discipline of writing matters more than the medium.

A Simple Daily Entry Template

DATE: ____________  ALTITUDE SLEPT: _____m  ALTITUDE TRAINED: _____m

MORNING PHYSIOLOGY
SpO2: ____%  RHR: ____bpm  HRV (rMSSD): ____  Body weight: ____kg

WELLNESS (1–5)
Sleep quality: __  Fatigue: __  Motivation: __  Appetite: __  AMS symptoms: __

SESSION LOG
Type: ___________  Duration: ______  Volume: ______
Intensity: HR avg/peak ___/___  Pace/Power: ______
RPE: ___  Lactate (if tested): ____
Notes: ____________________________________________________

NUTRITION/HYDRATION
Fluid intake: ____L  Iron sources: ____  Supplements: ____
Notes: ____________________________________________________

DAILY SUMMARY / COACH NOTE:
____________________________________________________

Common Logging Mistakes

Inconsistent timing: Morning physiology only has meaning if collected at the same time, in the same position, with the same protocol every day. Variation in measurement conditions creates noise.

Logging data but never reviewing it: A log that is never reviewed is just an archive. Schedule weekly review sessions into the camp.

Only logging the bad days: The best information comes from tracking the full arc—when you felt bad, when you turned the corner, when you peaked. Gaps in the record make trend analysis impossible.

Ignoring the post-camp window: Many athletes log meticulously at altitude and then stop the moment they return home. The post-camp data is where you measure the actual return on investment.

Key Takeaways

1. Log daily morning physiology (SpO2, RHR, HRV, body weight) to track acclimatization in real time.
2. Use a daily wellness questionnaire — 5 items, 60 seconds — to capture symptoms that objective metrics miss.
3. Establish a sea-level baseline before arriving at altitude so changes are interpretable.
4. Review your log every 5–7 days during camp to guide load adjustments.
5. Continue logging for 3–4 weeks post-camp to quantify the performance peak and timing.
6. Accumulate camp-over-camp data to build a personal altitude physiology profile that improves preparation every year.

Want a ready-to-use altitude training log template? Subscribe to the AltitudePerformanceLab newsletter and get our downloadable Google Sheets altitude tracking template with built-in trend charts.