A performance diagnostic report is only really valuable if you can also correctly place the most important terms in it. Many athletes see values like Critical Power, VO2max, FatMax or VLamax, but don't know exactly what these metrics actually mean in training or in a race.
That is exactly what this article is for. It explains the central terms from the report in understandable language, without watering down the sports-science statement. That way a collection of data becomes a real aid for training, pacing and race planning.
In this article you will learn:
- what CP and FTP really mean
- why VO2max is important, but should never be considered on its own
- what FatMax and VLamax say about your rider type
- how to read training zones, the Power Duration Curve and the Race Pacing Strategy sensibly
- what the difference is between measured, modelled and estimated values
Many athletes first focus in the report on the biggest number or on the seemingly "best" value. That is understandable, but often leads in the wrong direction. A good report shows not only how capable you are, but also how your performance is composed and how you can use it sensibly in training and racing.
Anyone who really understands their report can train much more precisely. You recognise better whether the biggest lever lies in aerobic development, in threshold performance, in load tolerance, or in pacing. That is exactly why it's worth understanding the most important terms cleanly once.
1. Why a glossary in the performance report makes sense at all
Modern performance diagnostics today delivers considerably more than just a threshold power or a VO2max. A good report combines performance data, physiological classification and practical conclusions for training and competition. That is very valuable, but it also brings a challenge: many terms sound technical, even though in practice they can be very easy to use.
The goal of a glossary is therefore not to define every term academically. The goal is to quickly show you which metric stands for what, how reliable it is, and what practical significance it has for you.
2. Critical Power (CP): the most important reference value in the report
Critical Power, CP for short, is one of the most central values in the entire report. Simply described, it is the highest power you can still maintain relatively stably over a longer period without fatigue immediately escalating sharply. It is therefore a very important reference value for training zones, pacing and performance modelling.
In practice, CP is especially useful because many other parts of the report build on it directly or indirectly. When training zones are defined, when race tactics are derived, or when modelled long-term performances are classified, CP is usually the basis. That's why it's worth seeing this value not just as a number, but as a kind of performance anchor for your entire report.
3. FTP: the practical threshold value for training and racing
FTP stands for Functional Threshold Power. In the context of your report, it corresponds to the modelled 60-minute power value. It is particularly important because it is widely used in training practice and is intuitively understood by many athletes.
While CP comes more from a performance-model perspective, FTP is often the more tangible term in everyday coaching and training. It helps to plan intervals, to classify race performances and to better calibrate your own sense of effort. Anyone who knows their FTP value can steer many training sessions and time-trial efforts much more deliberately.
4. VO2max: the maximal aerobic engine size
VO2max describes the body's maximal oxygen uptake. It is a central marker for aerobic performance capacity and is usually shown in the report both relatively and absolutely.
The relative VO2max is given in ml/kg/min and takes body weight into account. It is especially helpful when you want to compare athletes or better classify performance on climbs. The absolute VO2max in L/min, by contrast, shows how much oxygen can be processed in total, independent of body weight.
But what matters is this: a high VO2max alone does not yet decide actual race performance. It says a lot about potential, but only in interplay with CP, FTP, threshold behaviour, economy and pacing does it become clear how well that potential can really be used in a race.
5. Fractional Utilization: how well you can use your VO2max
Fractional Utilization describes what percentage of your maximal oxygen uptake you can actually use at threshold or at Critical Power. Simply put: how close do you get with your stably sustainable power to your maximal aerobic engine?
That makes this value very interesting. Two athletes can have a similar VO2max, but the one with the better Fractional Utilization can ride closer to their maximum without collapsing prematurely. That's why this value is often very meaningful for time trials, longer climbs and, in general, for how usable your aerobic capacity is.
6. W/kg: why relative performance is so important
W/kg means watts per kilogram of body weight. This value shows not only how much power you put out, but sets the power in relation to your body weight. Especially in endurance sport, this is enormously important.
On flat courses or in time trials, absolute power often plays a big role. But as soon as it goes uphill, W/kg becomes especially relevant. That's why it makes sense to look at both absolute wattage values and relative values. Only together do they give a complete picture.
7. FatMax: where your fat metabolism works hardest
FatMax denotes the power at which your fat oxidation is highest. That does not automatically mean that this intensity is the best training zone for everything. Rather, it means that in this range your body provides an especially large amount of energy from fat.
This is interesting above all for long endurance efforts and for classifying your metabolic characteristics. Athletes with a well-developed fat metabolism can often work more economically at moderate loads and spare carbohydrates for longer. FatMax is therefore not a "more is better" value, but a marker for how your metabolism works in the lower to middle intensity range.
8. VLamax: what this value reveals about your rider type
VLamax is a modelled value for maximal glycolytic performance capacity. Somewhat simplified, it describes how strongly your anaerobic metabolism can provide energy in the short term. This is especially interesting for rider types who excel at attacks, peak efforts or short hard loads.
What's important here: VLamax is not a classic "higher is always better" value. A higher value can be advantageous in some disciplines, rather disadvantageous in others. For an explosive rider it can be a plus; for an athlete focused on long, constant efforts not necessarily. That's why VLamax says less about "quality" than about performance character and profile.
9. Athlete Radar: the profile picture of your performance
The Athlete Radar visualises several performance dimensions at once. It is not meant to simply show you whether you are "good" or "bad", but how your profile is composed.
It's especially important here that not every axis may be interpreted in the same way. Some values stand more for performance level, others more for rider type or metabolic characteristics. The radar is therefore not a ranking, but rather a quick visual summary of your individual distribution of strengths.
10. Power Duration Curve: your performance across different durations
The Power Duration Curve shows which power you can produce, or are modelled to hold, across different durations. It connects short explosive efforts with medium loads and longer sustained performances in a single representation.
That makes it especially valuable, because it can immediately make visible where your profile is pronounced. Some athletes are strong over short to medium durations, others rather over longer constant loads. In combination with the table, the curve becomes a very practical tool for planning training and competition more realistically.
11. Power Duration Table: concrete values instead of just curves
The Power Duration Table supplements the curve with concrete power values for specific durations, for example 5, 20, 60 or 90 minutes. This is especially helpful because athletes and coaches often work with concrete durations.
A modelled 20-minute value helps, for example, with intense intervals or longer climbs, while a 60-minute value is directly relevant for FTP and threshold work. A 90-minute value, by contrast, can be very useful for longer competitions or efforts with an endurance focus.
12. Training zones: how intensity is translated into practice
Training zones turn the raw data of the report directly into usable practice. They divide your performance into ranges such as Recovery, Endurance, FatMax, Tempo, Threshold or VO2max.
The actual advantage lies in the fact that training thereby becomes structurable. Instead of just riding "easy" or "hard", you can target loads deliberately at specific physiological goals. Good training zones thus create the bridge between diagnostics and everyday training.
13. Heart-rate zones: the sensible complement to power
Besides the power zones, HR zones can also be very valuable. They help to look at intensity not only via watts, but also via the body's response.
This is especially helpful when conditions such as heat, fatigue, altitude or long load duration make pure power-based control more difficult. Heart rate doesn't replace power, but complements it sensibly. Especially in longer endurance sessions or when power data availability is limited, this can be very useful.
14. Substrate oxidation: where your body gets its energy from
Substrate oxidation describes which energy carriers your body draws energy from at a given load — above all from fat and carbohydrates. This part of the report helps to understand how your metabolism changes as intensity rises.
At lower intensity, the fat share is typically higher. As load increases, carbohydrate usage usually rises. That's exactly why this part of the report is not only interesting from a sports-science perspective, but also practically relevant for long races, fueling and load management.
15. Fat oxidation and carbohydrate oxidation: two sides of energy metabolism
Fat oxidation describes how much energy per unit of time is provided from fat. Carbohydrate oxidation correspondingly shows how strongly carbohydrates are used as an energy source. Both quantities together give a good picture of how your body covers loads energetically.
For practice this means: the longer and more moderate the load, the more important the ability to use fat efficiently becomes. The more intense the load gets, the more the importance of carbohydrates generally rises. This shift also explains why pacing and fueling are so closely connected.
16. CHO: the abbreviation for carbohydrates
CHO is simply the common short form for carbohydrates. In the report this abbreviation usually appears in tables or graphics in which carbohydrate consumption or estimated carbohydrate usage is shown.
What's important here is to distinguish between estimated usage and recommended intake. Not everything the body consumes in carbohydrates in total has to, or can, be taken in at exactly that amount during a load. That's why CHO in the report should always be classified cleanly.
17. Race Pacing Strategy: the practical translation for competitions
The Race Pacing Strategy is one of the most practical parts of the report. It translates the performance data into concrete target ranges and tactical hints for different event types, such as time trials, road races or gran fondos.
The great added value lies in the fact that it makes visible not only what you are capable of, but also how to apportion that performance sensibly. Good pacing strategies help to avoid overdoing it, to use energy reserves better and to ride races more under control.
18. Altitude-Adjusted Performance Targets: placing performance at altitude correctly
As altitude increases, the available amount of oxygen changes, and with it the achievable performance changes too. This is exactly where the Altitude-Adjusted Performance Targets come in. They show, in modelled form, how certain performance ranges can shift with altitude.
This is especially valuable for training or racing in the mountains. Anyone who transfers their sea-level values unchanged to 2000 metres quickly runs the risk of riding too hard. The altitude-adjusted target values help to plan more realistically.
19. Measured, modelled, estimated, assumed: why this matters
Not every value in the report has the same methodological status. Some values are directly measured, others modelled, estimated, or calculated on the basis of assumptions.
That is nothing negative — on the contrary: good reports often combine measurement and modelling. What's important is only that you classify this cleanly. A directly measured value is to be judged methodologically differently from a modelled target value or an assumed efficiency value. It is precisely this distinction that makes a report serious and traceable.
20. Conclusion: a good report is more than just numbers
A performance report is only really useful when it doesn't just show values, but also helps to understand those values correctly. Terms like CP, FTP, VO2max, FatMax, VLamax or pacing are not ends in themselves. They are tools to steer training, race apportionment and development more deliberately.
Anyone who understands their report not only trains more precisely, but can also make better decisions in competition. That is exactly why it's worth getting to know the most important terms cleanly once — and not just looking at the biggest number in the PDF.