Focus Duration & Type – Knowledgebase

Focus Duration measures the type of effort an activity targets by analyzing the balance of strain on Low, High, and Peak energy systems, not the ride’s length. It expresses this as a point on your power-duration curve, helping classify workouts, guide training, and connect your current riding style to performance goals within Xert.

Definition

Focus Duration describes what type of effort an activity, workout, or training period is centered around. It does not represent how long your ride lasted or how long you expect your race to be.

Instead, Focus reflects the combined demands placed on your three energy systems — Low, High, and Peak — and expresses that balance as a single point on your power-duration curve.

In simple terms:

Short Focus Duration → More sprinting and high-intensity strain
Long Focus Duration → More steady endurance strain

Even if you are training for a multi-hour event, your Focus Duration may be relatively short if the event includes punchy climbs, attacks, or repeated hard efforts.

What It Represents

Every power output uses a combination of your three systems:

Low (Threshold Power system)
High (High-Intensity Energy system)
Peak (Peak Power system)

Xert calculates how much strain each system contributes during your activity, then compares that distribution to your power curve and converts it into a duration.

For example:

If most of your strain comes from Peak and High systems (e.g., repeated sprints), your Focus Duration will be short (2-3 min)
If your activity produces some mix of Low, High, & Peak XSS (like a group ride or a race), Focus falls in the middle (5-10 min)
If there is very little High or Peak strain, the focus duration will be very long (>20 min) and the activity is effectively classified as Endurance.

Focus is not based on average power. It reflects the distribution of strain, including efforts performed under fatigue.

How to Interpret Focus Duration

Think of Focus Duration as a point on your power curve.

If an activity has a 5-minute Focus, the overall strain resembles your 5-minute power demands.

Shorter Focus → Greater stress on High and Peak systems
Longer Focus → Greater emphasis on the Low (Threshold) system

Important Note: If you plan to race or ride aggressively, you need to train more than just FTP! Focus helps ensure your training reflects the real demands of competition.

Focus Type & Athlete Type

Focus Duration and Athlete Type share the same duration-based naming system, primarily derived from Road Cycling terms. The idea is to make it easier to connect the riding that you have been doing with the type of riding which you wish to improve.

Focus Duration	Athlete Type	Description
2 min	Road Sprinter	Explosive power and repeated short anaerobic efforts. Ideal for riders who rely on high Peak & High energy system output in sprint finishes or during sharp accelerations.
3 min	Pursuiter	Sustained high-intensity efforts slightly longer than pure sprinting. Emphasizes strong anaerobic capacity - pushing big watts for short periods of time.
4 min	Puncheur	Powerful efforts on short climbs and punchy terrain. Blends anaerobic strength with short sustained power.
5 min	Breakaway Specialist	High-intensity efforts that can be sustained long enough to separate from the group. Strong High system contribution.
6 min	Rouleur	Hard, steady efforts at high power. Suitable for rolling terrain, strong tempo riding, and breakaway work.
8 min	GC Specialist	Sustained climbing and high-threshold efforts. Emphasizes durability and repeatable high power.
10 min	Climber	Longer sustained efforts at or near threshold. Ideal for extended climbs and prolonged attacks.
20 min	Sprint Time Trials	Strong threshold performance combined with small ability to surge. Balances steady, sustained power.
> 20 min	Endurance	Long-duration steady efforts powered primarily by the Low (Threshold) system. Minimal High and Peak strain.

If recent rides show a short Focus Types (e.g., Pursuiter/3 min power, Breakaway Specialist/5 min power), your training has emphasized high-intensity efforts. If your goal is longer sustained performance, you may choose an Athlete Type aligned with longer durations.

This shared duration-based language connects past performance with future progression.

Focus Power

Your Focus Power is the power you can sustain for your selected focus duration, calculated from your current Fitness Signature.

For example, if your focus is Rouleur (6-minute power), your Focus Power is the highest power you can hold for 6 minutes. If your focus is Climber (10-minute power), it's the power you can hold for 10 minutes. Focus Power changes as your Fitness Signature changes — improving fitness raises it, while losing fitness & signature decay lowers it.

Focus Power appears on your Forecast AI Chart when you have an active Forecast AI plan. The chart shows your Focus Power projected forward over the course of your plan — letting you see how strong you're expected to become at the duration you care about most.

How Xert Uses Focus

Focus Duration is used to:

Classify Workouts and Activities
Score Training Suitability
Guide XATA & XFAI Training Recommendations
Shape Forecast AI planning
Track long-term progression

Xert calculates Focus every second of your ride and aggregates it across the entire activity. On a larger scale, Xert looks at your Low, High, & Peak training loads across a training period to determine your overall progression focus.

Specificity Rating (Advanced Concept)

Focus is tightly connected to Specificity Rating, which is expressed as a percentage:

100% (Pure) → Most work was performed near the Focus power
Moderate % (Mixed) → A combination of work above and below Focus power
Low % (Polar) → Mostly low intensity with short hard efforts

Specificity describes how tightly your work clustered around the Focus Duration Power. Read more here.

Where You’ll See It

As such a vital aspect of the signature, Focus is seen throughout the platform:

On Activity Details pages
In Workout Library & Recommended Training
In Program Tab

Common Misunderstandings

Focus is not average power. It reflects strain distribution, not a simple mean value for the entire ride.
A Short Focus doesn’t mean short ride. A 4-hour race with many attacks can still have a short Focus Duration. It just means that your HIE & Peak Power become more imporant for that type of riding & racing.
Even relatively long endurance rides can have a shorter Focus duration if they are hard. While most strain might be placed on the Low system, any hard attacks or efforts will make the Focus shorter.

Related Terms