The standard conditioning ratio: 45 seconds on, 15 off, three rounds through five movements. Long enough to reach a real working heart rate, short enough to hold your form.
| Warm-up | 60s |
|---|---|
| Work | 45s |
| Rest | 15s |
| Rounds | 3 |
| Exercises | 5 |
| Rest between exercises | 30s |
| Total time | 16:55 |
Forty-five seconds is past the point where the body's fastest energy system can carry you, so you finish each interval genuinely working rather than just moving quickly. Fifteen seconds of rest is not full recovery — by round three you are working from an elevated baseline, which is where the conditioning effect comes from.
People with a base level of fitness who want a proper conditioning session. This is the ratio most group-fitness classes are built on.