Summit Feature: Fitness & Freshness

The Analysis Pack includes advanced insight on when to push your limits and when it's time to take it easy.

Training should be fun and uncomplicated – two words rarely associated with spreadsheets full of data. Fitness & Freshness lets you analyze all your activities with heart rate or power data in one place. You’ll be able to quickly assess if you’re approaching a peak in performance or a deep valley of overtraining so you can train effectively, minimize risk of injury and race at your best.

We know it can be hard to tell if your workouts are really making an impact, especially if you train across different sports. We developed Fitness & Freshness to make it easy for you to track your fitness over time, compare with past seasons, and spot trends – if the graph is trending upwards, you know you’re getting fitter!

While it's pretty simple to tell if a graph is skyrocketing or not, the details can give you a better understanding of what's going on. We’ve broken down each element of the graph so you’ll be able to easily analyze your fitness.


Assigning a number to fitness is a complex task, but it's critical to get right, so we sought help from the experts. For heart rate activities, we measure your total cardiovascular effort using Relative Effort, which we developed with input from sports-focused data scientist Dr. Marco Altini and then calibrated it based on data from thousands of activities across a wide variety of athletes. Power numbers come from your activity's training load metric and then there was still the tricky bit of quantifying the effect of all these efforts over time. For that, we apply an impulse-response model that stems from the work of Dr. Eric W. Banister. This allows Fitness & Freshness to capture both the build up of fitness as well as the loss of fitness during a break.

The small number to the side of your current fitness score tells you how your fitness has changed over the past seven days – this is a great way to measure the impact your current training is having.

Want to see how it maps onto individual activities? Underneath the graph you can see a bar chart of each activity. Races will be highlighted in orange so you can easily analyze their effect.


Always feel like you’re dragging your feet? Or your muscles always ache? Athletes aren’t always honest with themselves when they’re tired, so we wanted Fitness & Freshness to be able to help you prevent burnout and overtraining. We model fatigue the same way as fitness but over a shorter time scale, so it's quick to rise if you're going hard on back-to-back days, but it'll also soon dip down if you take an ample period of rest. If you see your fatigue level is way above your fitness, it might be wise to take a bit more time to recover before your next workout – your future self will thank you!


A high fitness score doesn’t always mean you are ready to PR, but it might mean that with a little tapering, you could shed some fatigue and be ready to fly on race day. This is what the form score is all about, which models the difference between your fitness and fatigue to help you from crossing the fine line between training hard and overdoing it. If your form score is deep in the negative, it's likely that you'll need some easy days before you’ll be back at your best.

Summit members with the Analysis Pack will see Fitness & Freshness on the web under the Training tab. You can track your fitness over the last six months, the last year or over your whole time on Strava. All you have to do is keep using a power meter or heart rate monitor and we’ll do the rest. Just check in periodically to see if your fitness is still on an upward curve!

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