Synthetic demo. Scores use generated heart-rate samples and sample HR settings.
How Training Strain works
Longer sessions add load; harder minutes count more. Effort is measured against resting and maximum heart rate. We add measured load across sessions, then convert the total to a 0–100 score. Session scores cannot be added together.
This first version covers recorded exercise. Heart rate can underrepresent strength work and short explosive efforts. Sleep, HRV and Body Battery remain separate recovery signals.
Resting HR used
49 bpm Synthetic demo baseline
Maximum HR used
190 bpm Synthetic demo setting
Method v1. Heart-rate reserve = (HR − resting HR) ÷ (maximum HR − resting HR). Raw load = minutes × (reserve ÷ 0.70)³, accumulated from valid recording intervals. Score = 100 × (1 − exp(−raw load ÷ 60)). The scale is provisional and is not equivalent to another product's score.
Activity analysis
Prewritten example
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Through the session
Heart rate average 101 bpm
More about this session
Open the details that matter to you.
Session totals & training effectMore from your watch