RPE and Session Rating: The Simplest Load Tool That Works

The single most useful training-load tool that exists in tennis costs nothing, takes ten seconds per session, and most adult players have never used it. Session-RPE — the rating of perceived exertion applied to a whole training session — produces a workload number with predictive value for adaptation, fatigue, and injury risk that competes with much more expensive technologies. The research base behind it is two decades deep. The barrier to using it is not money or complexity. It is the discipline of doing it every session, the same way, for long enough that the trend matters.

What session-RPE actually is

The Rating of Perceived Exertion is a subjective intensity scale, most commonly the Borg CR10 or its modified Foster version: zero is “nothing at all,” ten is “maximal.” Used during exercise, it measures momentary intensity. Used after a session — typically thirty minutes after, when the body’s central perception has stabilized — it gives a single number reflecting the global intensity of the entire training session. That number, multiplied by the duration of the session in minutes, gives a workload value in arbitrary units. Sum across the week, and you have a weekly workload (Foster et al., 2001).

The validation work on session-RPE is extensive. It correlates strongly with objective intensity measures like heart rate zone time, blood lactate, and energy expenditure in a wide range of sports including racquet sports. Where the correlation is weaker — extremely short, high-intensity intervals — the tool is also less commonly needed. For the typical tennis training session, mixing drills and points and conditioning, session-RPE captures the global load better than any single objective measure.

What it does not measure is mechanical load — specifically, the impact load on joints from running, jumping, and hitting. A heavy serve-practice session may produce a moderate session-RPE while loading the shoulder heavily. Session-RPE is a metabolic and central load metric. Mechanical load needs its own accounting.

The simple arithmetic that turns it into a tool

For each session: rate the global intensity from one to ten, thirty minutes after finishing. Write the rating times the duration in minutes. That number is the session load in arbitrary units (sometimes labeled “AU” or simply “RPE-minutes”). Sum across the seven-day rolling window — that is the acute load. The four-week rolling average is the chronic load.

The acute-to-chronic workload ratio is the published metric of interest. A ratio of roughly 0.8 to 1.3 is generally considered the “sweet spot” for adaptation without elevated injury risk. Below 0.8 may suggest detraining; above 1.5 is associated with sharply increased injury risk in racquet sport populations (Gabbett, 2016). This is not a prescription. It is a pattern that has held up across multiple sports and is worth checking against in tennis.

For the adult competitive player, the simplest weekly use is: total this week, total this rolling four weeks, divide. If the ratio creeps above 1.3 for more than a week, the next week’s training should be intentionally lighter. If the ratio drops below 0.8 for more than two weeks, the next month is probably going to feel like rebuilding rather than maintaining.

Where session-RPE outperforms more expensive tools

The honest comparison is interesting. Session-RPE does not require a heart rate monitor, a GPS unit, a power meter, or any device beyond a notebook or a phone note. The signal it produces, summed over weeks, predicts injury and fatigue trajectories with accuracy comparable to multi-sensor systems in many published comparisons (Halson, 2014). For a competitive adult, the simplicity is the feature, not the limitation.

The reason it competes so well is that perceived exertion integrates a lot of information the wearable cannot see. A session at moderate heart rate that follows a poor night’s sleep, low fuel, and existing muscle soreness will produce a higher RPE than the same session in a rested state. The body is reporting that the session was harder, which it was. A heart rate monitor would read the same number on both days and miss the difference.

The other underappreciated feature is that session-RPE works perfectly for indoor tennis, where GPS does not. For dryland conditioning, weight room sessions, and the broad spectrum of training a tennis player does, session-RPE is the only common currency that captures all of it on a single scale. A weekly load total that includes a tennis session, a strength session, and a conditioning session would otherwise require three different measurement systems.

Common errors that turn it into noise

Session-RPE breaks down quickly under sloppy use. The most common errors I see in adults who try and then abandon it:

• Rating during the session rather than after. The rating drifts toward the worst moment of the session. Wait thirty minutes after the session ends — by then, the central perception has settled and the rating reflects the global session.
• Rating different aspects on different days. Some days players rate “how hard it felt physically,” other days “how mentally taxing it was.” The rating has to be one thing every session — typically “overall intensity, all factors combined.”
• Treating the rating as binary. Adults love categorical thinking — “easy day” or “hard day.” But session-RPE is meant to use the full one-to-ten scale, and a six is meaningfully different from a seven for the workload sum.
• Skipping low-RPE sessions in the log. A two-out-of-ten session still produces load. Skipping it produces a workload total that under-counts and miscalibrates the chronic average.
• Adjusting the scale between weeks. The scale only works if it is consistent over time. A player’s seven this month should mean the same as a seven six months ago. If the scale drifts, the rolling averages become meaningless.

The simplest discipline that prevents most of these errors is: rate every session, the same way, even when you forget at first and have to estimate retroactively. Two months of consistent ratings — even imperfect — is more useful than two months of carefully calibrated occasional ratings.

When to overrule the RPE number

The danger with any single-number tool is treating the number as the truth. RPE-based workload tells you what the body experienced. It does not tell you what is sustainable for this individual at this point. Two players with identical workload numbers may have very different actual fatigue states because of differences in life stress, sleep, illness, age, or training history.

The overrule rules are simple. If perceived recovery is low for three consecutive days, reduce load regardless of where the chronic average sits. If injury symptoms appear, reduce load and investigate, regardless of the workload number. If illness arises, the chronic average goes on pause. The workload number is a guide. The body still has the final vote.

The other useful overrule is the qualitative: a player who can tell you exactly why a session felt hard (“legs heavy from Monday’s intervals,” “shoulder slightly stiff,” “slept badly”) is using their RPE intelligently. A player who reports “felt easy, but I do not know why” or “felt hard, but I cannot say what hurt” is producing ratings that may be drifting in calibration. Pay attention to the explanations as much as to the numbers.

A weekly template that fits an adult schedule

For a competitive adult playing three to five tennis sessions a week plus one or two off-court sessions, the simplest weekly RPE template looks like this. Two sessions in the six-to-eight range — these are the hard sessions, where adaptation work happens. One or two sessions in the three-to-five range — these are the moderate sessions, where pattern work and technique development happen. One session at one-to-three — this is the active recovery session that most adults skip and should not.

The total weekly load lands in the 1,500–3,000 RPE-minutes range for most competitive adults, depending on weekly hours. Under 1,000 is undertraining. Over 4,000 is approaching the upper edge that adult bodies usually handle without injury accumulation. This is a rough envelope, not a prescription, but it is a useful sanity check against the actual numbers a player generates.

One thing to do on court tomorrow

Tomorrow’s session: when it ends, set a thirty-minute timer. When the timer goes, write a number from one to ten in a notebook or a phone note next to today’s date and the session duration. That is your first entry. Do it again the next session. And the next. Three months of consistent entries will give you the first useful workload number you have ever had on yourself. Two weeks will not. The discipline is the tool.

Related in this series: HRV Monitoring in Tennis Players · Periodizing an Adult Competitive Year · Load Monitoring for Injury Reduction · Microcycle Design for Tennis

Selected reading:

• Foster, C., et al. (2001). A new approach to monitoring exercise training. Journal of Strength and Conditioning Research, 15(1), 109–115.
• Gabbett, T. J. (2016). The training-injury prevention paradox: Should athletes be training smarter and harder? British Journal of Sports Medicine, 50(5), 273–280.
• Halson, S. L. (2014). Monitoring training load to understand fatigue in athletes. Sports Medicine, 44(Suppl 2), S139–S147.
• Impellizzeri, F. M., et al. (2004). Use of RPE-based training load in soccer. Medicine & Science in Sports & Exercise, 36(6), 1042–1047.

Written by Emre Köse Tennis Coach · Beykoz Tennis Club

Tennis coach at Istanbul Beykoz Tennis Club for over 12 years. Graduate of the Coaching Education programme at Marmara University Faculty of Sport Sciences.

• 12+ Years on Court
• Graduate of Marmara University Faculty of Sport Sciences

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