Time Valley

This is a timed session, with intervals marked by a whistle. You will start with a four-minute effort and work your way down to a one-minute effort, then back up to a four-minute effort. Each effort is followed by a recovery period that is half the duration of the effort.

1. 4 minutes of effort
2. 2 minutes of walk/jog recovery
3. 3 minutes of effort
4. 90 seconds of walk/jog recovery
5. 2 minutes of effort
6. 1 minute of walk/jog recovery
7. 1 minute of effort
8. 30 seconds of walk/jog recovery
9. 1 minute of effort
10. 30 seconds of walk/jog recovery
11. 2 minutes of effort
12. 1 minute of walk/jog recovery
13. 3 minutes of effort
14. 90 seconds of walk/jog recovery
15. 4 minutes of effort
16. 2 minutes of walk/jog recovery