What is FTP? Functional Threshold Power is the highest mean average power you can maintain for one hour. This intensity level correlates well with anaerobic threshold, lactate threshold and ventilatory threshold, but, can be measured in the field without the need of a laboratory and qualified sports scientists. It is also often impractical and mentally challenging to calculate threshold power via a 60 minute test, so we use a 20 minute test and scale the value down by 5%. This value is then used to set all your power training zone intervals.
What does THR mean? Threshold Heart Rate is the highest mean average heart rate you can maintain for 20 minutes. This intensity level correlates well with anaerobic threshold, lactate threshold and ventilatory threshold, but can be measured in the field without the need of a laboratory and qualified sports scientists. This value is then used to set all your heart rate training zone intervals.
What is T-Score? This value is a calculated score used to objectively measure rides completed with power data. The formula takes into account both the ride intensity and duration. If you are working to a plan, then a session will have a target T-Score – in which case you need to ride to both the specified duration and intensity to reach the desired goal. Generally speaking, a T-Score of 30 would be an easy hour recovery ride, 120 would be a solid 2 hour training ride, and 300 would be a massive Sunday epic.
What is CTL? Chronic Training Load is a way of objectively measuring your general fitness. It is the long term, daily T-Score average of your rides. i.e., your daily T-Score average over a long period of time. To increase your CTL you are doing (on average) rides with a higher T-Score – this can be performed through either longer rides or more intense rides. CTL is a great way of tracking your overall fitness.
What is ATL? Acute Training Load is a way of objectively gauging your current training load. It is the short term, daily T-Score average of your rides ie your daily T-Score average over a short period of time. When compared with your CTL, you can see if you are currently riding above or below your long term average. By comparing your ATL and CTL you can track if you are building or recovering, and the comparison between the two values gives your TSB or freshness score.
What is TSB? The Training Stress Balance is really a freshness score. It is calculated simply by comparing your CTL to your ATL. A negative number will indicate you have been doing “harder” rides then your long term average. Harder could be either in duration or intensity. When your freshness score is negative you will likely feel tired and fatigued. In contrast a positive score indicates you are doing a lower load than your long term average. This is what you want for a taper or recovery period. In these periods you should start to feel refreshed and ready to knock out a personal best.
