Understanding Strava's Fitness & Freshness Feature: Managing Training Cycles for Peak Race Condition

What is Strava Fitness & Freshness

Strava’s Fitness & Freshness is a training load analysis tool available to Strava Summit subscribers (the basic version is currently free to use in Taiwan). Conceptually, it is very similar to TrainingPeaks’ PMC (Performance Management Chart), tracking your fitness, fatigue, and race form through three curves.

This feature has a much lower barrier to entry than TrainingPeaks, making it suitable for amateur athletes who don’t want to pay extra but still want a systematic approach to managing their training.

The Meaning of the Three Curves

Fitness Curve

Corresponds to TrainingPeaks’ CTL, calculated as the weighted average of your training load over the past 42 days. Each time you complete an activity, Strava updates this curve based on “Relative Effort.”

• Curve steadily rising: Training volume is progressively increasing, fitness is continuously improving
• Curve flat: Training maintains the current level, fitness neither increases nor decreases
• Curve declining: Insufficient training volume or currently tapering, short-term fitness loss

Fatigue Curve

Corresponds to ATL, calculated as the weighted average of training load over the past 7 days, reflecting your current level of fatigue.

• Fatigue curve above fitness curve: At a peak of training stress, be alert to overtraining
• Fatigue curve dropping rapidly: During taper, fatigue is dissipating

Form Curve

Corresponds to TSB (Training Stress Balance), calculated as: Form = Fitness − Fatigue

How to Read Strava’s Training Cycle

A typical 3-month race season preparation would show the following curve trends on Strava:

Weeks 1–8 (Base Building Phase):

• Fitness curve climbs slowly
• Fatigue stays within Fitness
• Form remains slightly negative (-5 to -20)

Weeks 9–10 (Intensification Phase):

• Add high-intensity intervals; Fatigue temporarily exceeds Fitness
• Form may drop to -25 to -35
• This is the toughest period, but you must push through

Weeks 11–12 (Taper Phase):

• Significantly reduce training volume (maintain a small amount of high intensity)
• Fatigue drops rapidly, Fitness drops slightly
• Form continues climbing into positive territory

Race Day Goal: Form reaches +5 to +20

The Calculation Logic Behind Relative Effort

Strava’s Relative Effort is a training load metric based on heart rate zones:

• Each heart rate zone has a different “effort coefficient”
• The highest heart rate zone has a much higher effort coefficient than lower zones
• If no heart rate data is available, Strava estimates using speed/power

Note: Without a connected heart rate device, the accuracy of Relative Effort drops significantly, and the reference value of the Fitness curve is also diminished.

Comparison with TrainingPeaks

Practical Recommendations

• Check the curves once a week, focusing on whether Form stays above -30
• Start observing taper effects 3 weeks before a race; if Form is rising too slowly, accelerate the volume reduction
• Connect a heart rate strap or power meter to make Relative Effort data more accurate
• Manually log weekly training volume (kilometers or hours) alongside the curves for dual tracking of training trends

Conclusion

While Strava’s Fitness & Freshness is not as refined as TrainingPeaks, it is practical enough for most amateur athletes. The most important thing is to build the habit of “regularly checking the curves and making decisions based on the numbers”—having Form in positive territory before a race is confidence backed by data, not just a feeling of being ready.

Related Reading

• Strava Training Analysis: Key Metrics Beyond KOM You Should Focus On
• Strava Running Features Fully Explained: Segment Timing, Training Log, and Social Interaction Complete Guide
• How to Read Strava Data Correctly: Making Data Your Tool for Improvement
• Post-Race Cycling Analysis: Using Strava and TrainingPeaks to Find Improvement Points