Training Peaks' PMC graph and Strava's Fitness and Freshness graph can look confusing at first. There are a bunch of lines and dots that go up and down, and in the beginning you've probably got little to no idea as to why. This blog post will go through every aspect of both graphs, explaining what each element means, why they go up or down, and exactly how much training you should be doing at any given point.
Like our athletes that we coach, you'll require a heart rate monitor or a power meter in order to use these graphing systems from Training Peaks or Strava. We recommend using a power meter over a heart rate monitor, though a heart rate monitor is better than nothing.
Training Peaks - PMC
In the graph above you can see the following, which will be explained in this post: TSS and Intensity Factor of each ride (red and blue dots), Fitness (blue line), Fatigue (pink line) and Form (orange line).
Strava - Fitness & Freshness
Like the PMC Graph, the Strava Fitness & Freshness graph also features the TSS or Training Load/Suffer Score of each ride at the bottom in a bar graph and the Fitness (accumulated dark grey line), Fatigue (standard grey line) and Form (light grey line) on the main graph.
What Each Aspect Means
TSS / Training Load / Suffer Score
TSS or Training Stress Score on Training Peaks, or Strava's Training Load (using power) / Suffer Score (using heart rate), is essentially how difficult a training session is. It takes into account the intensity (Intensity Factor = the ratio of a workout in relation to your threshold (1.0)) of the whole workout or at specific time interval in relation to your threshold power or heart rate and the duration to make the calculation. To put the numbers in perspective, 100 TSS is essentially 60 minutes at your threshold and, therefore, the highest TSS you can generate per hour. Below we have included a chart showing the approximate values of TSS you will accumulate for each training zone per hour, minute or quarter minute.
If you're just starting out cycling with a low level of fitness, then 100 TSS will feel quite strenuous. However, if you train consistently your fitness will rise over time, and 100 TSS will feel much easier. A low TSS on a given day will likely not be felt in your legs the next day, while a very high value of TSS will be felt even days later. See the chart below for given TSS of particular rides and the effects they have on your body.
In the next section we will go over how TSS accumulates to determine your fitness.
Fitness / CTL
Your fitness on both TP and Strava is calculated as an exponentially weighted average of your TSS/Training Load/Suffer Score for your workouts in the last 3 months, with more recent workouts having more of an effect than older workouts. So essentially if you performed a 100 TSS workout every day, your fitness would eventually reach 100. We will speak more about where you should try and get your fitness too, or how quickly to build it up later.
Fatigue / ATL
Fatigue is also an exponentially weighted average of your TSS/Training Load/Suffer Score for your workouts, but in the last 2 weeks. Therefore, your fatigue will be more volatile, increasing and falling much faster and further than your fitness.
Form / TSB
Form is the difference between the level of your Fitness/CTL and your Fatigue/TSB, (CTL - ATL). If your CTL is at 50 and your ATL is at 70 then your TSB will be at -20.
How To Train - 6 Do's and Don'ts
1. Import All Your Old Ride Data
It takes around 6 weeks of data for the graphs to be accurate in determining your current fitness. The more data you have, the more you'll be able to reflect on where you've been in the past and compare it with where you are currently.
2. Don't Increase Your Fitness/CTL Too Quickly The biggest and most common mistake athletes make when they coach themselves and start using the PMC or Strava Fitness & Freshness graphs, is to do excessive training to increase their fitness rapidly. While being enthusiastic about your training is a good thing, you want to make sure you're not ramping up your CTL too quickly. An increase of around 5-8 CTL points per week is a good aim for when you are building up your fitness. While some athletes can handle more than this, for the majority, increasing at this rate will avoid burning out.
3. Keep Your Form/TSB In The Right Zones
For your peak training periods, the best Form or TSB value zone has been determined to be around -10 to -30. It is a wide range of values due to the great variability between what each athlete is able to cope with. While going below -30 TSB won't render you instantly burnt out or sick, you'll want to make sure you don't spend to many successive days in this zone. The exact number of days you can spend below -30 TSB and how low you can get your TSB to before burning out will vary greatly between athletes.
During your rest weeks, you should be getting your TSB to -10 to +5. In terms of peaking for big races or events, the ideal TSB value differs greatly between athletes and the type of event your taking part in. Some athletes will perform best at +10 while others feel best at -5. The data shows that somewhere between -5 to +20 is a good range to have your TSB sitting on a race day. If your race or event lasts for multiple day or is long in duration, then we recommend that you aim for the higher end of the scale. Though, you may feel better at the lower end of the scale when training for shorter and sharper events.
Like many of these broad recommendations, going off your experience and trial and error will become more useful in your future training endeavours and where you target your various CTL/ATL/TSB values to be at.
4. Take Rest Weeks
Most coaches will prescribe 2 to 4 weeks of hard training followed by a rest period, whether it be a few days to a week of rest (easier riding and days off). This allows your body to recover from the training during the hard weeks and super-compensate to a higher level than you were before. Without proper rest you will end up on a downward spiral of reduced performance leading to overtraining. It's a good idea to start out by incorporating a 3 to 1 ratio of training and rest (3 weeks hard, 1 week easy). If you feel like you need rest weeks more or less often you can schedule your rest weeks accordingly.
5. Retest Your FTP Regularly
You should be retesting your FTP every 4 to 6 weeks to ensure that your TSS values for your rides are accurate. An example of where it can go wrong is the situation where your FTP rises, but you do not adjust it, causing your TSS values to show up higher than they should and all of your CTL, ATL and TSB values to go off track.
6. Train For The Type of Fitness You Want
If bike touring is your thing and you just want large amounts of steady state endurance, then structure your training accordingly. If you want to become a crit specialist then you'll likely want to be doing much different training than a bike tourer.
Get A Coach
We're not just saying it because we want you to sign up to be coached by us, but having an experienced coach who knows all of this like the back of their hand, through experience with many athletes, will ensure you the greatest chance of success in becoming the strongest and fastest version of yourself. If you haven't already, check out the video below from our head coach Sam, discussing his background and what we offer at Velo Goals in our Bronze, SIlver and Gold Training Plans.