Power Analytics
Power data: the objective measure of performance.
Heart rate drifts with heat, fatigue, and caffeine. Pace changes with wind and terrain. Power is instantaneous, objective, and repeatable. If you have a power meter, Gneta turns that data into the metrics coaches actually use: NP, TSS, IF, and your power duration curve.
What You See in Gneta
Normalized Power Per Activity
Average power lies to you. A ride with steady 200W and a ride alternating between 100W and 300W feel completely different, yet their averages are identical. Normalized Power (NP) accounts for the physiological cost of variable effort using a 30-second rolling average raised to the fourth power. Gneta calculates NP for every ride and run automatically from your Garmin data.
TSS & IF Calculations
Training Stress Score (TSS) quantifies the total training load of a session relative to your FTP: a one-hour ride at FTP equals exactly 100 TSS. Intensity Factor (IF) tells you how hard the session was. An IF of 0.75 is a solid endurance ride, 0.85–0.95 is tempo to threshold, and above 1.0 means you were above FTP. Gneta computes both for every power-enabled activity.
FTP Trend Tracking
Your Functional Threshold Power is the single most important number in cycling. It anchors your zones, TSS, and IF. Gneta tracks your FTP over time, whether you set it manually, detect it from 20-minute or 60-minute efforts, or sync it from your Garmin. Watch your threshold climb over a training block or catch early signs of overtraining when it starts to drop.
Power Duration Curve
Your power curve maps peak power across every duration, from 5-second sprints to 60-minute threshold efforts. Gneta builds your curve from all synced activities and overlays it against previous periods so you can see where you are gaining and where you have gaps. A flat spot at 3–8 minutes might reveal a VO2max limiter. A drop-off after 20 minutes might signal threshold weakness.
Free for all Garmin watches and power meters
Understanding Power Metrics
Power-based training transformed cycling because it removed subjectivity. A watt is a watt whether you are fresh or fatigued, riding into a headwind or drafting in a pack. But raw watts alone do not tell the full story. That is where Normalized Power, Intensity Factor, and Training Stress Score come in.
Normalized Power (NP) was developed by Dr. Andrew Coggan to reflect the true metabolic cost of variable-power efforts. The algorithm takes a 30-second rolling average of your power data, raises each value to the fourth power, averages those, then takes the fourth root. The fourth-power weighting means that hard surges are weighted disproportionately, because physiologically, going 50W over threshold for 30 seconds costs far more than cruising 50W under threshold saves.
Intensity Factor (IF) is simply NP divided by your FTP. An IF of 0.75 means you rode at 75% of your threshold, a typical endurance pace. An IF of 0.95 means you were near your limit for the whole ride. If you record an IF above 1.05 for over an hour, it is a strong signal that your FTP needs updating upward.
Training Stress Score (TSS) combines intensity and duration into a single number. The formula is: (seconds x NP x IF) / (FTP x 3600) x 100. A one-hour ride at FTP scores exactly 100 TSS. Weekly TSS totals are a powerful way to track volume: recreational riders often accumulate 300–400 TSS per week, serious amateurs 500–700, and professionals 800–1200+.
The power duration curve maps your best power output at every duration. Your 5-second peak reflects neuromuscular power. Your 1-minute peak reveals anaerobic capacity. Your 5-minute best correlates strongly with VO2max. And your 20–60 minute output defines your threshold. Overlaying curves from different time periods instantly shows where you are improving and where you might have a physiological limiter worth targeting.
Gneta computes all of these automatically from your Garmin power data. No exports, no spreadsheets, no third-party calculators.
Frequently asked questions
Turn watts into insight.
No credit card required. Works with every Garmin watch and power meter.
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