Forty-five seconds of work against ten of rest — a 4.5:1 ratio that lands squarely between the [40/10](/hiit-timer/40-10) and the [50/10](/hiit-timer/50-10). Eight rounds run 7:10, and the ten-second rest is a breath and a grip reset, not a recovery.
The extra five seconds over 40/10 matter more than they look: forty-five seconds is too long to push as one hard surge, so you settle into an output and defend it while the rest gives almost nothing back. It rewards movements you can grind at a steady pace — rower, bike, ski erg, kettlebell swings. Start a notch below what feels possible, because at this ratio a fast opening unravels the back half. Open the preset in the editor to add a warmup or stretch the rest while you build up.
Equal work and recovery — the dependable 1:1 where the last round still matches the first. The cardio base you’ll actually come back to.
All-out efforts with a full walk to recover between them. One for the track, a hill, the bike, or the rower.
Work-heavy, recovery-light — sustained minute-long pushes for building an engine that holds up under fatigue.
A full minute of work to twenty seconds of rest — the 3:1 grind for holding a strong output once the recoveries stop being enough.
The 2:1 workhorse of conditioning circuits and bootcamps: long efforts, short rest, fatigue stacking as you go.
Minimal-rest conditioning that puts the heart rate up early and keeps it there. Pace it to last, not to peak.
The bootcamp class clock — station-friendly rounds where the rest is just long enough to rotate.
An easy on-ramp to interval training: short work, real rest, every round at the same honest effort.
Tabata’s relentless cousin — barely-there rest and maximum sweat in well under ten minutes.
The hub’s toughest ratio: a near-minute of work against a single breath of rest. A grinder for the patient.
The hub’s most extreme ratio — five seconds is a reset, not a rest. A brutal six-minute finisher; pace it like a grind.
Four 4-minute near-max efforts with 3 minutes easy between, plus a warm-up and cool-down. The classic VO2 max protocol for runners, cyclists, and rowers.
Eight all-out 30-second sprints with 90 seconds of easy recovery between, plus a warm-up and cool-down. The eight-sprint protocol popularized by Phil Campbell.