Training Peaks Scores.. What Do They All Mean And How Can You Or Your Coach Use And Misuse It?

From RPG coaches Kyle Buckingham and Tim Reed

Training Peaks remains the dominant software platform for endurance sports coaching and for good reason. The level of analysis available to coaches, simple to use phone app for athletes and the superb integration with devices enhances the athlete/coach experience while reducing the challenges of online coaching drastically. Contrast to 10-15 years ago where athletes were emailed a PDF or Word document to a time now where you wake up, head out the door and the session your coach has built is already uploaded into your watch or bike computer to guide you through the session, to then be auto uploaded to software that the coach can view within seconds of you finishing the session. It’s safe to say Training Peaks has made online coaching a vastly greater experience.

Aside from the most obvious perks just mentioned Training Peaks also provides different metrics that can be of incredible value and surprisingly many athletes (and some coaches) have little understanding of what it all means and how it can be of use. While the scores are far from perfect and nothing compares to the old school very regular consistent conversations with your coach on how you’re feeling, we hope to enlighten you on what all initials mean and how you can apply them to train and recovery better.


What is CTL/Fitness?

Chronic Training Load (fitness) combines duration and intensity to provide a value of how much an athlete has trained historically. Training Peaks calculates CTL, by default , as the exponentially weighted average of the daily TSS for the the past 42 days.

What is TSB/Form?

TSB (Form)- Training Stress Balance represents the difference in the balance of training stress. TSB provides a measure of how much an athlete trained recently (ATL), compared with how much an athlete trained historically (CTL).

What is ATL/Acute Training Load?

Acute Training Load (Fatigue) combines duration and intensity to provide a value of how much an athlete has recently trained. TrainingPeaks calculates ATL, by default, as the exponentially weighted average of daily TSS for the past 7 days.

What are the benefits?

Coaches can identify patterns with each individual athlete for both maximising training response and achieving peak race day performance on the days that really matter. Not surprisingly it can vary wildly between individuals and can take a coach quite some time to find the right recipe which is why chopping and changing coaches every 6 months rarely works out well for athletes. As a simple example, athlete A may stop making making gains and tip into the land over training as shown by sickness or propensity for injury when he reaches a TSB of -25 and that might be the tipping point in addition to the athlete feedback to pull back for 3-5 days to allow the body to refresh. Athlete B may be more resilient and enjoy better ‘recoverability’ and be able to spend longer periods dipping as low as -40 to -50 TSB before needing to pull back for some recovery time.

Staying on TSB and variations between athletes. The level of freshness (positive TSB score) required for an athlete to perform at their best on race day becomes more apparent the longer you coach an athlete. Athlete A has achieves peak performance for their fitness at + 20 TSB while athlete B may need an even longer taper to hit +40 TSB before he starts slicing through the competition.

The CTL(fitness) score can offer a nice way for a coach to gradually progress training for an athlete. Ie- Athlete A might have historically handled a jump in CTL of 10 points per week while athlete B might have a huge training history and his recovery scores show a jump of 15 points or even higher is no problem. CTL can also offer a nice general target of a level of fitness for peak performance. Higher is not necessarily better after a certain point and everyone’s sweet spot before the need for some time to back off and bounce back either physically or psychologically can differ a lot.

Image- @wes_thompsonn

What are the potential downsides of getting too stuck in the numbers?

As professional athletes / ‘addictive type Aers’ we’ve experienced first hand the perils of getting too bogged down in all the numbers in defining our fatigue, readiness to race and tracking my fitness over time at the expense of ignoring all the common sense metrics. Common sense metrics that simply can’t always be captured in Training Peaks scores including; do I feel tired, am I grumpy as hell, enjoying zero sex drive, sore in the muscles? Or the opposite; feeling positive, loving the training, not feeling like you need a break and no injuries flaring up etc.

While the Training Peaks scores are an excellent tool that coaches can and should include in their coaching, it has to be recognised that there are still many shortcomings of the algorithms. The most obvious one being that the only stress really accounted for and measured is your training stress. Any coach worth their salt will tell you stress is stress no matter if it’s work, relationship or which ever other delightful form it presents itself. Unfortunately it all affects recovery and performance even if your Acute Training Load doesn’t include it into it’s total.

Athletes who ignore their other ‘common sense metrics’ can allow the numbers to get into their head during sessions or even before a race with thoughts like ‘I’m not fit enough because my CTL isn’t high enough to do well or I shouldn’t train today simply because I’ve cracked -30 TSB. The Training Peaks scores work particularly well paired with common sense metrics and work most optimally when left to the coach to make more objective calls based off all the feedback and numbers than most athletes can make when it comes to decisions regarding themselves.


Up there with how the Training Peaks numbers can result in a detriment is the comparison pitfall. Roosevelt was right ‘Comparison is the thief of joy” but in training and racing it can also be the thief of results. What is optimal for you in the Training Peaks numbers is likely to be different to someone else. In fact, what is optimal for you now, will almost certainly differ from what is optimal for you in 5 years.

Key takeaways. Please don’t bother with comparisons between athletes, have an understanding of what the metrics mean but ideally leave how it will influence your training to your coach provided of course you know they’re keeping a close eye on them. Remember that the Training Stress numbers are most powerful when combined with good old fashioned common sense and abundant communication between athlete and coach.

Looking for a coach?
4 x Professional Ironman Champion, 1 x Amateur Ironman World Champion Kyle Buckingham is one of the few RPG coach’s who currently has capacity. Shoot us an email at [email protected] to find out more.