Wondering what those training terms used on Strava really mean? See our glossary below to learn how to make the most out of your training on Strava.
Your Functional Threshold Power (FTP) is the maximum average power that you can hold for one continuous hour. For example, if you were to ride a 40k time trial in 60 minutes at an average power of 275W, your FTP would be 275W.
FTP is the keystone to training with power. It allows Strava to determine how hard a ride is for you. You doing 300W might feel much different than someone less trained doing 300W and FTP allows us to gauge just how hard segments, rides, and even weeks or months of training were for you!
Calculating Your FTP
We recommend you test for your FTP at least every few weeks to a month while you're training. Here are some tips to get the most out of your FTP testing:
It's extremely taxing on your body (and your training program) to continuously push out 60-minute max efforts. It's also difficult to find a stretch of road where you can ride for 60 minutes uninterrupted and maintain a steady wattage. Thus, the easiest way to calculate your FTP is to test your best average power for 20 minutes. We believe 20 minutes is enough time to stress the same physiological systems as a 60-minute effort would and it is easier to consistently do within your season.
- Try to reproduce the same conditions each test — this means use the same stretch of road or always use the same trainer/rollers
- Make sure you are fresh (the previous few days should be light in terms of training load)
- Properly warm up
Weighted Average Power
When you ride with a power meter, you'll notice how your power jumps all over the place based on the terrain, grade, wind, and other factors. Weighted Average Power looks at all of this variation and provides an average power for your ride that is a better indicator of your effort than simply taking your average power. It is our best guess at your average power if you rode at the exact same wattage the entire ride.
Total Work, expressed in kilojoules (kJ), is simply the sum of the watts generated during your ride. There is a close 1–to–1 ratio with Total Work and Calories expended during a ride.
Intensity is our way of showing how difficult a ride was as compared to your FTP. We look at your Weighted Average Power for the ride and compare it to your FTP. If your Weighted Average Power was 250W and your FTP 300W, the Intensity would 83%. It's very possible to have an Intensity of over 100% if the ride was shorter than an hour.
- Endurance / Recovery Ride – 65% and lower
- Moderate Ride – 65-80%
- Tempo Ride – 80-95%
- Time Trial or Race – 95-105%
- Short Time Trial or Race – 105% and higher
Intensity on Segments gives you a simple visual indication of how hard you went on a given segment by comparing the effort with your best power for the duration of that segment over the last 6 weeks.
For example, if you maintained 300W for a 10-minute segment and your best 10-minute power over the past 6 weeks was 330W, your segment intensity will be 90%.
We calculate Training Load by comparing your power during your ride to your FTP and determining how much load you put on your body during the workout. Training Load is a great way to determine how much rest you need after your workouts. The guide below will tell you how long after a workout it will take you to fully recover:
- About 24 hours – 125 and lower
- 36-48 hours – 125-250
- At least 3 days – 250-400
- At least 5 days – 400+
The Power Curve shows your best average power for time periods of 1 second up to the length of your ride. We search your entire ride and find these best efforts and you can compare them with your best efforts for your last 6 weeks, the current year, years in the past, or all-time!
The Power Curve can be displayed in Watts (W) or Watts per Kilogram (W/kg.)
While the Power Curve shows your best efforts for given periods of time, Power Zone charts take each 1 second of power of your ride and put it into a bucket. The buckets are based on your FTP and are as follows:
- Active Recovery (<54% FTP) – Social pace with very little physiological effect on your body. Can be used in between intervals and for recovery rides.
- Endurance (55% - 74% FTP) – Easy pace that you could ride all day long. Conversation is still possible with little concentration required.
- Tempo (75% - 89% FTP) – Brisk pace that can be maintained for a few hours that requires concentration when riding alone. Breathing in tempo is rhythmic and may become strained at the upper end of this zone.
- Threshold (90% - 104% FTP) – Moderate to hard effort and leg sensations that can be maintained for up to 1 hour. Conversation is difficult and concentration is required.
- VO2Max (105% - 120% FTP) – Power that is primarily taxing your VO2Max system. Leg sensations are high and conversation is not possible. VO2Max can be maintained for 3-8 minutes.
- Anaerobic (120% - 149% FTP) – Extremely hard efforts with severe leg sensations that can be maintained for 30 seconds up to 3 minutes.
- Neuromuscular (>150% FTP) – Sprinting power that is taxing your neuromuscular system and can be maintained for 1-20 seconds.
While fitness is a complicated concept, it can be simplified to just an accumulation of training. The Fitness Score is calculated using Training Load, to measure your daily training, and an impulse-response model to quantify its effect over time. This will intuitively capture the building up of fitness, as well as the loss of fitness during a break.
Conceptually, fatigue is easy to understand; it's that tired feeling which limits your performance. We model it the same way as fitness, but on a shorter time scale. You'll notice the score go up quickly after a couple hard days, but also go down quickly as you take a few days off.
Being in form, or "peaking," happens when one is very fit but not fatigued. Here we model this as the difference between your Fitness Score and your Fatigue Score.