Workouts / Interval
Interval
Hard Starts 5x4
5×4:00 hard-start VO2 intervals (30s @ 140% then 3:30 @ 105%) with equal rest.
Duration1:05:00
TSS62
IF0.76
Blocks5
Time1:05:00
TSS62
IF0.76
Profile
Targets in % FTP
100%50%0%
0:0032:301:05:00
Z1 46% · 30 minZ2 23% · 15 minZ4 27% · 18 minZ6 4% · 3 min
Intervals
5 blocksZ2
Warm-upBuild cadence
15:0060%Repeat 5×
Z6
IntervalHard start @ 140%
0:30140%Z4
IntervalSettle at 105%
3:30105%Z1
RecoveryEqual rest
4:0050%Z1
Cool-downEasy finish
10:0050%What it trains
VO2-focused intervals raise aerobic ceiling and repeatability for attacks, climbs, and hard surges.