G3 Exercise and Sports Science: Why Reaction Time Is Not Movement Time

The first event is the cue that starts the defined response task. The second is movement onset, using the criterion stipulated by the task. The third is the specified completion event. Our paper record supplies all three times on a common clock for each attempt.

This event-based definition matters because everyday phrases such as reacted quickly or finished fast can refer to different parts of the action. An observer might notice an early movement, while another notices only the final touch. They are not necessarily describing the same interval.

In this guide, reaction time means cue to onset, movement time means onset to completion and total means cue to completion. Some sources use response time differently, so we keep the full cue-to-completion label visible rather than assuming one term has a universal meaning.

The main task and success condition are stipulated as comparable for A and B. Both attempts reach the required endpoint successfully. No target distance, sporting technique or physical exercise needs to be invented to calculate the supplied intervals.

Begin by labelling the events, not by guessing which time represents a person's ability. A timing result belongs to a defined task, event criterion and attempt. Once those conditions are clear, subtraction becomes straightforward and the later interpretation can stay attached to the evidence.

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For Attempt A, the cue time is 0.00 seconds and movement onset is 0.18. Subtract the cue time from the onset time: 0.18 minus 0.00 equals 0.18 seconds. This is the reaction interval under our definition.

For Attempt B, the same calculation gives 0.25 minus 0.00, or 0.25 seconds. B's reaction time is longer by 0.07 seconds. In this timing comparison, A begins the movement sooner after the cue.

The conclusion concerns the supplied attempts, not an enduring ranking of two people. The letters identify records. We have no evidence about repeated performance, age, health, motivation or the cause of the difference. Those claims would go beyond the arithmetic.

Also avoid describing reaction time as a direct measurement of one isolated mental stage. The interval is operationally defined by observable events. It can include several processes before the detected onset, depending on the task and measurement method.

A clear answer states both the endpoints and the result. For example, Attempt A's reaction time is 0.18 seconds from the cue to the specified movement onset. That wording prevents the later completion time from being substituted accidentally and makes it clear what the numerical comparison does and does not describe.

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Attempt A begins at 0.18 seconds and finishes at 0.68. Movement time is 0.68 minus 0.18: 0.50 seconds. This interval begins only when the defined onset event occurs, not when the cue appears.

Attempt B begins at 0.25 and finishes at 0.61. Its movement time is 0.61 minus 0.25: 0.36 seconds. B's movement interval is shorter by 0.14 seconds under the stipulated comparable task conditions.

Do not report 0.61 as B's movement time. That number is the completion timestamp on the common clock and, because the cue is at zero, also equals its total cue-to-completion interval. It is not the time spent between onset and completion.

This is a common timestamp-versus-duration error. A clock reading identifies when an event occurs; a duration is the difference between two relevant event readings. If the cue were at another clock time, the distinction would become even more obvious.

Keep the two boundaries in the working: completion minus onset. A student who writes the names before substituting numbers is less likely to choose the visually largest time automatically. The calculation then answers a specific performance question rather than attaching a familiar label to whichever number looks like a finishing result.

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The total cue-to-completion interval for A is 0.68 minus 0.00, or 0.68 seconds. It also equals reaction time plus movement time: 0.18 plus 0.50. For B, the total is 0.61 seconds, matching 0.25 plus 0.36.

The two intervals join at movement onset. They do not overlap and no extra gap has been omitted under our definitions. This is why adding them reconstructs the complete interval from cue to completion.

Do not add the reaction time to the completion timestamp when the cue is zero. For A, 0.18 plus 0.68 would count the first interval twice and produce an incorrect 0.86. The 0.68 already includes the time before onset.

A useful checking equation is total equals completion minus cue, and also equals onset minus cue plus completion minus onset. The shared onset terms cancel. The algebra expresses the same event sequence as the paper record.

There is no need for advanced mathematics to understand this. Identify where each interval starts and ends, then check that the parts cover the whole exactly once. That habit is valuable in many performance-analysis tasks because a correct-looking sum can otherwise combine overlapping measurements or leave an unmeasured portion out of the claimed total.

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Attempt B finishes at 0.61 seconds, earlier than A's 0.68. Yet B starts moving at 0.25, later than A's 0.18. The shorter total therefore cannot be explained by a shorter reaction interval in this supplied record.

B takes 0.07 seconds longer before onset but 0.14 seconds less after onset. The movement-time advantage exceeds the reaction-time disadvantage by 0.07 seconds, matching the total difference between the attempts.

This decomposition is more informative than saying B is faster. Faster in which interval? B is faster to complete overall and has the shorter movement interval; A has the shorter reaction interval. The apparently conflicting statements describe different measures and are compatible.

Do not infer why the movement interval differs. The record supplies times, not an account of technique, decision quality or physical capacity. A numerical explanation of how the total differs is not automatically a causal explanation of why the performer produced those times.

A strong short answer can state the contrast directly: B's total is shorter because its 0.14-second shorter movement interval more than offsets its 0.07-second longer reaction interval. This uses the actual evidence and avoids turning a finish-time result into an unsupported claim about reaction speed.

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Move the entire timing record five seconds later on the same clock. For A, the cue is now 5.00, onset 5.18 and completion 5.68 seconds. Reaction time remains 0.18, movement time remains 0.50 and the total remains 0.68.

The clock readings changed, but the event differences did not. This shows why the completion timestamp itself is not the definition of total response duration. It happened to match the total in the main case because the cue was assigned time zero.

For B, cue 5.00, onset 5.25 and completion 5.61 produce the same 0.25, 0.36 and 0.61 intervals as before. The comparison is invariant to this common shift in clock origin.

Students sometimes memorise use the last number for total. That shortcut fails once the cue is not zero. Writing completion minus cue is more reliable and just as quick once the events are labelled.

This chapter also helps when reading a video timeline or a data table that begins before the cue. The start of the recording is not necessarily the start of the measured interval. Use the task-defined event, not the first visible clock reading. A clear event definition prevents a simple time-origin difference from being mistaken for a performance change.

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One second contains 1,000 milliseconds. A's reaction time of 0.18 seconds is 180 milliseconds, its movement time of 0.50 is 500 milliseconds and its total of 0.68 is 680 milliseconds. B's corresponding values are 250, 360 and 610 milliseconds.

Changing units does not change the performance relationship. B still has the longer reaction interval and the shorter movement and total intervals. The numerical values become larger because the unit is smaller, not because the action became slower.

Do not compare 180 milliseconds directly with 0.25 seconds as though both numbers used the same scale. Convert them to a common unit first. Likewise, keep a time difference separate from a percentage difference; 70 milliseconds is a duration, not 70%.

The difference in total is 0.07 seconds, or 70 milliseconds. The movement-time difference is 0.14 seconds, or 140 milliseconds. Keeping the units visible makes the offsetting relationship easier to check.

A useful answer labels every final result and uses one consistent unit within a comparison. There is no benefit in switching repeatedly between seconds and milliseconds unless the task requires it. The learning goal is to preserve the same interval while changing its representation, not to make the calculation look more technical through extra conversions.

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Suppose a separate fictional record supplies only a cue-to-completion total of 0.60 seconds. It does not state movement onset. Several combinations of reaction and movement intervals could produce that total, such as 0.20 plus 0.40 or 0.30 plus 0.30.

Both combinations fit the total under the stated additive model. The total alone does not identify which occurred. Assigning a reaction time would require an additional onset record or other information that establishes the relevant boundary.

This is the information limit at the heart of the article. A finish time is useful for the whole-task question, but it cannot automatically answer every question about the components. More precise wording does not create missing data.

Do not fill the gap with a typical value remembered from another study. Different tasks and measurement definitions can produce different results, and our record does not identify a representative population or protocol. The appropriate answer is that the separate intervals are not determined by this information alone.

A student should be able to explain what additional observation is needed: the specified movement-onset event, recorded on the same relevant timeline. This turns uncertainty into a practical next evidence question. It is stronger reasoning than either guessing a component or declaring the complete timing record useless because it answers only the total question.

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Movement onset may be detected by an agreed observable event or an instrument criterion. A study might use a first detected motion, a button release or another specified marker. These definitions need not identify exactly the same instant in every task.

The primary research linked with this guide makes its event definitions explicit. Our paper model does the same by supplying a defined onset time. We are not importing a particular research apparatus, threshold or expected value into a school task.

If one attempt uses the first visible hand motion and another uses release of a button, the results may not be directly comparable as though the measurement boundary were identical. The physical action and the criterion both matter.

This does not mean one definition is always wrong. It means the measure must be interpreted in relation to its operational definition. A useful analysis asks what event the number actually marks before comparing it with another record.

For an actual assessment, follow the supplied task and school instructions. Do not invent a movement-onset threshold because a paper example elsewhere used one. In our main case, onset is stipulated and comparable, so the subtraction is valid. In a real data collection, consistency of the boundary would be part of what needs checking before making a strong performance comparison.

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The completion event also needs a clear criterion. It might be contact with a specified target, crossing a defined line or another task-specific endpoint. Our main case stipulates that both attempts complete the same required action successfully.

A different endpoint can change movement time without changing the underlying movement in the way a reader assumes. Measuring to first contact is not necessarily the same as measuring until a final settled position. Do not compare them casually under one label.

Success is a separate condition from the clock stopping. A trial can end at an incorrect target or with a rule violation. If the task requires accuracy, the timing result must be considered alongside whether the required action was completed correctly.

The paper record deliberately gives comparable successful attempts so the central timing distinction is clear. It does not claim that speed is the only relevant dimension of sports performance. Later examples introduce a wrong-target result to show why that matters.

Before interpreting a finish time, ask what event ended the interval and whether the task's success criterion was satisfied. A complete answer can then distinguish a short duration from a successful performance. This prevents an attractive numerical result from concealing that a different action or an unsuccessful endpoint was measured.

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The main case defines onset after the cue, so both reaction intervals are positive. In a separate hypothetical trial, suppose movement begins at 0.05 seconds before the designated cue. That is not evidence of a negative reaction duration to that cue in the intended response task.

It indicates that the action began before the event chosen as the reaction interval's starting point. The task rules and record would need inspection. Anticipation, an incorrect cue definition or a timing error are possibilities, but the data alone do not choose the cause.

Do not celebrate an earlier movement automatically as better reaction performance when it violates the task's requirement to respond after the cue. Nor should a student diagnose intentional rule-breaking from one unusual timestamp without evidence.

This example shows why event order is part of validity. A cue-to-onset interval assumes the relevant cue precedes the response onset under the stated task. If that order does not hold, a mechanical subtraction needs interpretation rather than a triumphant ranking.

In a real sport, anticipation can have a legitimate role depending on the situation and rules. That broader idea does not change the definition of our controlled paper reaction task. Keep the task boundaries visible rather than treating one timing convention as a judgement about every form of skilled anticipation.

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Introduce Attempt C as a separate fictional extension. Its cue is at 0.00, onset at 0.10 and recorded endpoint at 0.50 seconds, but the record states that it reaches the wrong target. Its intervals are short, yet it has not completed the defined task successfully.

The timing arithmetic remains describable: 0.10 seconds before onset and 0.40 from onset to the recorded endpoint. However, calling C the best successful performance would ignore the supplied accuracy condition. The relevant judgement depends on the task, not only the smallest number.

Do not invent a penalty formula. If the question supplies one, apply it. If it does not, state the timing and the failure to meet the target criterion separately. A general observation about accuracy does not authorise an arbitrary adjusted score.

This helps explain why a coach or student may need more than a total time to evaluate an action. Accuracy, the decision made and the defined outcome can matter alongside timing. Our article focuses on interval definitions while preserving those wider evidence limits.

A concise conclusion could say that C is faster to the recorded endpoint but unsuccessful under the given target rule. That sentence keeps both facts. It avoids dismissing the timing information while also avoiding the misleading claim that faster must mean better in every performance context.

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Our main comparison stipulates the same task conditions and success criterion. Without that condition, a shorter movement interval might simply reflect a shorter required path, a different starting position or a different completion rule. The number alone would not isolate the reason.

Similarly, a reaction task with one known response is not automatically comparable with a task requiring a choice among several responses. The information and decision demands can differ. This guide does not supply such a manipulation or claim an effect size for it.

When a real question gives changed conditions, name them. They may be the point of the comparison. When conditions are unspecified, avoid claiming that an observed difference proves a particular personal quality or training effect.

The useful method is to separate descriptive comparison from causal explanation. We can describe A's and B's intervals from the supplied record. Explaining why they differ needs relevant evidence about the task, participant and conditions.

This distinction supports fair analysis. A student should not be labelled slow to react from a movement time measured under a different task, and a shorter total should not be treated as proof of superior information processing without the appropriate component record. Clear definitions and comparable conditions make performance feedback more specific and less likely to attach a broad judgement to the wrong measure.

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One attempt describes one recorded event. It does not establish a person's usual reaction time or movement time. Repeated comparable attempts can provide more information about the pattern, but they still belong to the task and measurement conditions used.

For an original illustrative set, A has reaction times of 0.18, 0.20 and 0.19 seconds, paired with movement times of 0.50, 0.48 and 0.49. Each total is 0.68. The mean reaction interval is 0.19 and the mean movement interval is 0.49 seconds.

A separate B set has reaction intervals of 0.25, 0.24 and 0.26, paired with movement intervals of 0.36, 0.37 and 0.35. Each total is 0.61. The means are 0.25 and 0.36, retaining the same descriptive contrast.

These are invented records, not a study sample or normative benchmark. They demonstrate how paired components can be summarised. They do not establish statistical significance, a training benefit or an enduring ranking between athletes.

If actual records vary, preserve that variation rather than selecting only a preferred attempt. Follow the task's rule for summarising results and describing exclusions. The learning aim is to use the evidence honestly, not to turn a small set of timings into a fixed identity or an unsupported prediction about future performance.

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For a complete matched set of attempts, the mean total equals the mean reaction time plus the mean movement time because each total is the sum of those two components. In the illustrative A set, 0.19 plus 0.49 equals 0.68 seconds.

The condition complete matched set matters. If reaction times are averaged from three attempts but movement times from a different selection, adding the means does not necessarily describe the same set's mean total. Missing records and exclusions need attention.

Label attempt numbers or another appropriate identifier so the components stay together. A table with the correct values in mismatched rows can create a false account of how an individual total was produced. Accurate arithmetic cannot repair incorrect pairing.

This guide makes no claim that every type of summary combines in the same way. A task asking for a median, best attempt or another measure needs that measure's appropriate interpretation. Do not assume a familiar identity for means automatically applies to every summary statistic.

The practical checkpoint is to ask which attempts each summary represents. Then calculate and state the result with the correct scope. This is a useful data-response habit within performance analysis: preserve the relationship between observations before reducing them to one number that appears easier to compare.

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A timing system records events with some resolution and uncertainty. For a separate illustrative video example recorded at 50 frames per second, adjacent frames are 0.02 seconds apart. That frame interval is relevant when deciding how precisely an event can be located from the frames alone.

This does not mean every event is automatically measured with exactly 0.02 seconds of error, nor that a displayed decimal proves that level of accuracy. Event criteria, synchronisation and the recording method also matter. The actual uncertainty needs appropriate information.

Our main times are stipulated paper values. We can subtract them exactly for the educational comparison, but we are not claiming a real instrument measured them without uncertainty. A separate physical investigation would need its own method and limitations.

Avoid making a strong performance claim from a difference smaller than the method can meaningfully resolve. Equally, do not dismiss all timing data merely because measurement is imperfect. State what the method supports and how the uncertainty affects the particular comparison.

For a school answer, use the precision supplied and follow the task's conventions. If measurement limitations are relevant, explain them specifically rather than writing human error as an all-purpose phrase. Identifying the event and recording limitation gives the reader a clearer reason to assess the result cautiously.

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Retain sufficient precision during the interval calculations, then present the answer in the form appropriate to the supplied data. In the main case, 0.68 minus 0.18 is 0.50 seconds. Keeping two decimal places makes the relationship with the stipulated timestamps easy to inspect.

Rounding every timestamp to one decimal place before subtraction can change the apparent component differences. The result would reflect both the original timing and the rounding choices. It is better to calculate from the supplied values first.

Conversely, adding many extra decimal places to a result does not create more measurement certainty. Reporting 0.500000 seconds from two-decimal paper timestamps is not evidence of a highly precise physical measurement. Numerical display and measurement quality are different concepts.

The same applies to a percentage comparison. It may be mathematically possible to calculate a relative difference, but the question must need it and the underlying measurement should support the interpretation. A clear difference in seconds is often enough for the main explanation.

The useful habit is to preserve the supplied information without disguising its limits. A student should be able to explain the event boundaries and the direction of the difference before choosing a number of decimal places. Precision in reasoning is more important than a long string of digits attached to an unclear measure.

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If a later attempt has a shorter total, that observation does not by itself prove a training programme caused the improvement. The change might involve reaction time, movement time, both or different task conditions. A causal claim needs more information than one before-and-after total.

Our A and B records are not labelled before and after training. Treating them as such would invent a study design. They are simply two fictional successful attempts supplied to illustrate the component distinction.

Even if a question explicitly supplies a training comparison, inspect what was measured and what else changed. The component data can show where the recorded time difference lies. They do not automatically explain the physiological, psychological or technical mechanism producing it.

This boundary is important for useful feedback. A student who finishes sooner because of a shorter movement interval should not be told that their reaction interval improved when the record shows the opposite. Accurate feedback identifies the measured change before proposing an explanation or next investigation.

The related eduKate faster-time-and-training-evidence guide develops causal caution more fully. Here, the immediate job is to preserve the event-based measures. A clear descriptive result is valuable on its own; it does not need an unsupported training story to become meaningful or encouraging.

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The fictional times are not normal ranges, selection standards or clinical thresholds. They should not be used to diagnose a student's health, label a disability or decide who is capable of participating in sport. No such evidence is supplied.

Likewise, the article does not prescribe drills, training loads or a plan to alter reaction time. A timing distinction can be learned on paper. Any actual physical activity should follow the relevant school guidance, appropriate supervision and individual circumstances.

Avoid turning a small measured difference into a judgement about effort or character. A longer reaction interval does not prove laziness, and a shorter movement interval does not establish better decision-making. The task and measurements describe specific features, not a complete person.

Optimistic feedback can still be precise. A student can learn to identify the relevant interval, calculate it accurately and explain what evidence is missing. Those are achievable analytical skills even when no claim about changing physical performance is being made.

The useful boundary is that performance analysis informs a defined question. It does not automatically authorise medical conclusions or personalised exercise advice. Keeping that boundary visible makes the educational example more responsible and helps readers focus on the actual learning gain: distinguishing the measured parts of a response rather than attaching broad labels to a total time.

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A concise answer to the main case should state that A has the shorter reaction time, while B has the shorter movement time and total cue-to-completion interval. Include the relevant values so the conclusion can be checked against the record.

Then explain the offset: B's reaction interval is 0.07 seconds longer, but its movement interval is 0.14 seconds shorter. The net result is a total 0.07 seconds shorter. That is a numerical account of the difference, not a claim about its cause.

Avoid writing B reacts faster because it finishes first. Replace reacts with finishes sooner overall if only the total is meant. If the task specifically asks about reaction time, use cue-to-onset data rather than a general impression of speed.

For a question with only the total, explain that the component intervals are not determined without onset information. Naming the missing event is more informative than saying not enough data without identifying what is needed.

Before handing in, check the endpoints, subtraction, unit and claim. The final sentence should describe the interval actually calculated. This simple review can repair an answer that contains correct arithmetic but assigns it to the wrong feature of performance, which is the central misconception this guide addresses.

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A parent can write cue, movement begins and action finishes on three cards or lines of paper. Place the main case's times beside them and ask the student which two events define each interval. No physical reaction test is needed.

If the student uses 0.68 as movement time, ask where that interval should start. If they assume the earlier finish means earlier reaction, compare the onset times directly. If they add the reaction time to the total, trace which portion has been counted twice.

These are different errors and need different repairs. A student may understand subtraction but misread the label, or understand the labels but struggle with decimal arithmetic. Isolate the actual difficulty instead of repeating a broad explanation of sports science.

Next move the cue to 5.00 seconds while shifting the other events equally. Ask whether the durations change. This checks understanding of timestamps without adding new physical or sporting demands.

Finish with a changed example and let the student explain it independently. The goal is a clear event map and a supported comparison, not a judgement about how quickly the student can move. A calm paper exercise can build confidence in performance analysis while keeping personal ability and health assumptions outside a record that does not establish them.

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English Across School Subjects helps with from, to, before, after, onset and completion. These small words define the measured interval. Faster is incomplete unless the explanation states faster in which part of the task.

Data-Response Questions supports keeping cue, onset and completion in separate columns and preserving the attempt pairing. It also helps distinguish a timestamp, a duration and a summary across attempts. The arithmetic depends on the correct reading of the record.

Writing and Revision helps turn the calculation into a precise comparison. Name the interval and values, then state the evidence boundary. Critical Thinking helps identify when a total cannot reveal its components or when a timing change does not establish a cause.

Learning Transfer supports the wider habit of defining start and end events before comparing durations. Different subjects may use different boundaries, so transfer the method of checking definitions rather than assuming the same timing labels everywhere.

The related ESS guides on outcome versus movement feedback, consistency and accuracy, and faster-time evidence address separate performance-analysis questions. Choose the one connected to the student's current difficulty, then return to a changed timing record. The useful outcome is an independent explanation of what was measured and what follows, not simply a larger vocabulary of sporting terms.

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Practice A supplies cue 2.00 seconds, onset 2.22 and successful completion 2.72. Reaction time is 0.22 seconds, movement time is 0.50 and the total is 0.72. The completion timestamp itself is not the total duration because the cue is not zero.

Practice B supplies cue 2.00, onset 2.30 and successful completion 2.65 under comparable task conditions. Reaction time is 0.30, movement time is 0.35 and total is 0.65. B finishes sooner but has a longer reaction interval than Practice A.

Practice C supplies only a total of 0.70 seconds. Can reaction time be calculated uniquely? No. The movement-onset boundary is missing. Several component pairs can produce that total under the additive model.

Practice D states that the fastest endpoint belongs to an attempt reaching the wrong target. Describe its time and its failure to meet the task's accuracy condition separately. Do not invent a penalty or call it the best successful attempt without a rule supporting that judgement.

For a final check, convert Practice A's 0.22-second reaction time to milliseconds: 220. Then explain why that conversion changes neither the interval nor the performance. A strong answer keeps events, units and claims aligned across the changed examples.

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Reaction time and movement time describe different intervals in the model used here. Cue to onset is not onset to completion, and neither should be confused with the whole cue-to-completion interval. A total can become shorter while one component becomes longer.

In the main record, A reacts in 0.18 seconds and moves for 0.50, totalling 0.68. B reacts in 0.25 and moves for 0.36, totalling 0.61. B's earlier finish does not prove an earlier reaction; the component record establishes the opposite.

Keep the wider limits visible. One attempt does not define a person, a total does not uniquely reveal its parts and a descriptive difference does not establish a training cause. Event definitions, comparable conditions and measurement information determine what a timing result supports.

For the next independent task, label the cue, onset and completion before calculating anything. Subtract the appropriate endpoints, check that the parts reconstruct the whole and write a conclusion naming the interval actually measured.

If the student can do that with a shifted clock origin or a new pair of records, they have learned a practical analysis method. The gain is not a claim about becoming a faster athlete; it is clearer, more accurate reasoning about what performance data mean.

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