Training load and form

How GSTS measures how hard you train, in plain words.

GSTS turns your heart rate into one number per workout, the load, then follows it over days and weeks.

Load of a workout

The higher your heart rate, the more each minute counts. GSTS splits your heart rate into five zones, from easy (zone 1, from half your maximum heart rate) to very hard (zone 5, from 90 % of it). A minute in zone 1 counts 1, a minute in zone 5 counts 5. The total is the workout's load.

A workout without heart rate still counts in your weekly time and distance, but its load is 0.

Fitness, fatigue and form

• Fitness is your load averaged over about six weeks: it grows slowly with regular training.
• Fatigue is your load averaged over about one week: it rises fast after hard days and falls fast with rest.
• Form is fitness minus fatigue, from yesterday's values. Negative form after a hard week is normal; positive form means you're fresher than your recent training.

The word next to your form

• Fresh (5 or more): rested; a good moment for a hard session or a race.
• Balanced (−10 to 4): training and rest are in step.
• Building (−30 to −11): you're training harder than usual; normal in a build-up week.
• Heavy load (below −30): much more than you're used to; consider an easier day.

The word appears after 28 days of data, when your fitness has had time to build up.

Last 7 days vs the last 4 weeks

GSTS compares the load of the last 7 days with your weekly average over the last 28 days. A much higher number means this week is harder than you're used to. It appears after 28 days of data.

Maximum heart rate

Zones depend on your maximum heart rate: see Maximum heart rate.

These numbers describe training, not health. GSTS is not a medical device and gives no medical advice. If you feel unwell, stop and talk to a doctor.