FITNESS PROGRESS — COMPARISON RECORD
Goal and the specific question I want to answer:
Measure, unit and reason it matches that question:
Task version / route / equipment / technique instructions:
Period A: dates, planned opportunities and actual observations:
Period B: dates, planned opportunities and actual observations:
Missing entries and whether the outcome is known:
Conditions that changed between observations:
What the recorded comparison shows:
What it cannot establish:
Health or recovery concern needing guidance:

NEXT REVIEW — DATA OR PLAN CHANGE
Known facts from the dated record:
Unresolved comparison or missing field:
Smallest useful recording improvement:
Appropriate routine or professional instructions to retain:
Next review date or agreed review point:
Reason for that timing, rather than a universal plateau deadline:
If changing the plan: what, when, why and who advised it:
Which old entries remain unchanged:
Question for a clinician or qualified exercise professional:
This worksheet does not diagnose a plateau or prescribe calories or exercise.

Choose a measure that answers your actual question
Use a small set of useful fields rather than collecting every available device number. One behavior measure and one task-specific observation may be enough for your current question. Keep medical measurements under the instructions of the professional who requested them.
Different questions need different measures
Question
Useful record
Necessary context
What this alone cannot show
Did I do the routine I planned?
Originally planned opportunities, actual attendance and actual activity.
Plan dates, moved or cancelled sessions and unknown outcomes.
Improved fitness, weight loss or the quality of every session.
Is this familiar walk becoming easier to repeat?
The same route or defined task, duration and a brief effort note.
Stops, hills, weather, load carried and changes in route.
A cause of the change or a clinical fitness assessment.
How did the same strength task compare?
Exercise version, equipment, sets and repetitions recorded separately.
Technique or range instructions, assistance and rest arrangement.
That more repetitions with a changed task mean greater strength.
What does my agreed weight record show?
Dated readings using the same units and agreed measurement method.
Missing readings, device changes and the plan followed with your care team.
Body-fat change, metabolic adaptation or a calorie prescription.
Is the routine workable in my week?
Actual time and access constraints; what happened when the plan changed.
Work, caring, transport, sleep and appropriate recovery needs.
That a difficult week reflects laziness or a need for punishment.
Write the measure's definition in plain language. “Session completed” might mean arriving, doing any activity, or completing the originally planned task; those are different counts. For a defined plan-and-actual record, use the 
workout adherence tracking guide
. This article starts with the next question: whether the available observations support a useful comparison.
Do not turn an optional outcome into the only measure of success. NIDDK notes that physical activity has important health benefits independent of weight loss. A scale reading therefore cannot stand in for every activity or fitness outcome.

Check whether you are comparing the same task
Conditions do not need to be perfectly identical for a record to help. They do need to be clear enough that a change is not silently attributed to fitness. Put a short note beside the observation when an important condition changes; compare a suitable subset or describe the difference instead of forcing every entry into one ranking.
A same-condition comparison checklist
Check
What to make explicit
If it changed or is unknown
Goal and task
The question and the actual activity being compared.
Separate unlike tasks instead of calling one a better result.
Definition and unit
Minutes, repetitions, distance or another clearly defined measure.
Resolve units and definitions before subtracting numbers.
Route or exercise version
Route, hills, assistance, equipment and intended movement.
Label the new version; keep the original entries.
Measurement method
Same timing method or device and an agreed procedure.
Mark a method change; do not assume readings are interchangeable.
Stops and rest
Whether the timing includes pauses and how rests were arranged.
Distinguish elapsed time from moving time; record relevant changes.
Effort and control
A plain-language effort note and the technique instructions followed.
Do not improve a number by changing the task or ignoring symptoms.
Relevant conditions
Weather, load carried and unusual schedule or recovery context.
Treat these as possible context, not proof of a cause.
Observation coverage
Dates, number of recorded opportunities and missing entries.
State what is absent before describing the pattern.
The 
CDC explains aerobic activity intensity
 using effort and the ability to talk: during moderate activity you can talk but not sing; during vigorous activity you generally cannot say more than a few words without pausing for breath. It also stresses that the same activity can feel different to people with different fitness and health. A brief effort note can add context, but it is not a calibrated test, medical screening result or target to chase.
For strength records, a repetition is a complete movement and a set is a group of repetitions. Record the exercise version and instructions as well as the count. This guide does not tell you to train to failure, change a prescribed technique or repeat a difficult task merely to obtain comparable data.

Separate a missing entry from a recorded zero
An empty field means you do not have that recorded value. It does not automatically mean no activity happened. You may know that a session was missed, know that some activity occurred but lack its duration, or know nothing about that opportunity. Keep those states separate.
Known, missing and changed activity records
Known situation
Honest entry
Conclusion you can make
You know the planned walk did not happen.
Missed; zero activity for that specific planned opportunity.
The planned opportunity was not attended; unrelated activity is a separate entry.
You know the walk happened but did not record its time.
Attended; duration unknown.
Attendance is known, but the activity-minute total is incomplete.
There is no entry and you cannot reliably recall the outcome.
Outcome unknown; no invented duration.
The period has a coverage gap; neither attendance nor duration is established.
The plan moved and the new date is known.
Original date and status; actual new date and result.
You can review the move while preserving what was originally planned.
A device failed or its method changed.
Record the failure or method change and any reliable remaining facts.
Some fields may remain useful; the missing measurement is not recovered by guessing.
For example, one fictional week has three planned walks. Two are recorded as 20 minutes each, while the third outcome is unknown. The record establishes 40 documented minutes and two known attendances. It does not establish exactly 40 total minutes or complete attendance of two out of three. If you later confirm the third was missed, date that correction and record the source of the information; do not fill it with a typical duration to make the week look smoother.
Likewise, “the average of three recorded observations” is a narrower statement than “my weekly average” if other intended observations are missing. Averages can summarize recorded numbers, but cannot recover missing ones or repair a changed measurement method. Show the dates and number of observations alongside any summary.
The next step may be a smaller, easier recording method: write the activity and actual amount soon afterward, or make a private paper note when the device is unavailable. You do not need to reconstruct every forgotten number. Keep “unknown” and start a clearer record from a stated date.

ANSWERED CASES

1. A familiar walk takes longer on a new hilly route with more stops. Does the time alone prove a fitness plateau?
No. The task and conditions changed, so the direct comparison is limited.
Record the route and stops. Different elapsed times do not establish a fitness change when the activity being measured is different.

2. A session happened but its duration is missing. Should its activity-minute field be entered as zero?
No. Attendance is known; duration is unknown.
A blank measurement and a confirmed missed session are different states. Keep the known fact and the missing field separate rather than inventing a value.

3. Three recorded readings have an unchanged average, but several intended readings are missing. Does that prove a plateau for the whole period?
No. It describes those three observations, with incomplete coverage.
State the dates, method and number recorded. A summary of available values cannot recover missing observations or diagnose why an outcome is unchanged.

4. Twelve assisted repetitions are compared with eight less-assisted repetitions. Is the larger count sufficient evidence of improvement in the same task?
No. The exercise version and assistance must be part of the record.
More repetitions can be useful to document, but a changed task is not automatically a stronger result in the original task. Keep technique and appropriate support in view.

5. An appropriate routine is repeatable, but the spreadsheet lacks route and timing definitions. What is the smallest useful next review change?
Clarify the task and measurement method, and mark earlier limitations.
A recording improvement addresses the known gap. It does not require replacing the whole routine, adding punishment sessions or changing food intake.

6. Pain or concerning symptoms occur before enough observations have accumulated. Should you keep exercising until the planned review date?
No. Stop as appropriate and seek suitable guidance sooner.
A data review cannot clear symptoms or impose a waiting period. Urgent concerns need urgent or emergency help, and existing professional instructions take priority.

Sources:
https://www.cdc.gov/healthy-weight-growth/losing-weight/index.html
https://www.cdc.gov/physical-activity-basics/adding-adults/what-counts.html
https://www.niddk.nih.gov/health-information/weight-management/choosing-a-safe-successful-weight-loss-program