Training calculators
Check whether weekly Zone 3 minutes are a deliberate tempo dose or are crowding out easy endurance work.
Updated 2026-06-08
Zone 3 training balance checker
Enter weekly minutes by zone to see whether Zone 3 is a controlled tempo dose or the intensity that is crowding out easy aerobic work.
Starting point
Easy share
83%
300 min in Z1-Z2
Zone 3 share
13%
45 min tempo
Hard share
4%
15 min in Z4-Z5
Weekly total
360 min
60 min above Z2
Readout
Your easy share is high enough that Zone 3 is probably a deliberate dose, not the default setting.
Zone 3 guardrail
For general endurance weeks, treat 20% Zone 3 as a soft ceiling unless the block is intentionally tempo-heavy.
Easy base
A 70% or higher easy share is a practical checkpoint before you add more tempo or threshold work.
How it works
Use this checker to audit your weekly intensity distribution. It is not a prescription, but it helps you spot the common pattern where moderate Zone 3 work quietly replaces easy aerobic time and leaves less recovery for true hard sessions.
How to use it
- Enter the minutes your watch or training log recorded in Zones 1 through 5 for the week.
- Compare your easy share, Zone 3 share, and hard share with the readout.
- Use the result as a weekly pattern check, then adjust based on your goal, recovery, and whether the Zone 3 work was planned.
Questions
Is any Zone 3 time bad?
No. Zone 3 can be useful for tempo, race-specific, and progression work. The concern is when it becomes the default intensity and crowds out easy volume or true hard work.
Why does the checker use a 70% easy-share checkpoint?
It is a practical endurance-training guardrail, not a universal rule. Many successful endurance plans keep most weekly time easy, then add smaller doses of tempo, threshold, and high intensity.
Should race-specific blocks always pass the checker?
Not necessarily. A tempo-heavy block can be useful and still look mixed. Use the readout to confirm the tradeoff was intentional and recovery is still strong.