4-6 Intervals,

A1. AMRAP 3
1000m BikeErg
Run for distance in the remaining time

A2. AMRAP 3
400m Run
BikeErg for distance in the remaining time

– Rest 2:00 between intervals –

Number of intervals. These intervals are more about quality than quantity. Only do the final intervals IF you’re confident you can stay close to or maintain your previous output.

Cool Down
A) 5:00 easy jog/walk/BikeErg

SESSION NOTES
Overview.
Short aerobic-capacity intervals. A1 starts with a bike effort before switching to running under fatigue; A2 flips that demand with a fast run into the bike. The goal is to manage the opening effort so you can still produce meaningful distance in the second half of each interval.

Effort.
Work at ~8.5–9/10. Each 3-minute piece should feel hard quickly, but you still need to leave room to push the second modality. The aim is to maintain (or stay close to) your paces throughout the intervals.

Feel.
Breathing spikes early and stays high throughout. A1 hits the legs on the bike before a run under fatigue. On A2 the run elevates heart rate fast, and the goal is to settle into your pace on the bike immediately. Across rounds, recovery is incomplete, so fatigue carries forward.

Adaptation.
Develops aerobic capacity and the ability to transition between modalities under high heart rate. Trains pacing control and the mental skill of pushing the output with fatigue.

Debrief. Take 2–3 minutes after the workout to reflect
– How much time did you have for the second movement in each interval?
– Were your distances consistent across rounds?
– Which transition felt harder: bike to run OR run to bike?
– What pacing change would help you get more work done after the buy-in next time?

Movement options. Change to other monostructural modalities (row, ski, Air/Echo bike) if needed.