Indoor air quality and ventilation

These notes combine advice from 11 reviewed passages across 10 workouts.

Overview

Coach’s claim

The space where you train needs airflow. Open a window to create air circulation in the workout room. [5] [6]

Coach’s claim

Insufficient oxygen makes you tire faster, and a lack of airflow can make you feel dizzy. [1] [6]

Effects of stale air

Coach’s claim

In a closed space without clean air, you can feel dizzy, and fresh air is needed. [3]

Coach’s claim

In a closed area, carbon dioxide can build up. When it is high, energy drops and you can use your mind less. [9]

Coach’s claim

If you suddenly become extremely tired during training, it can mean indoor carbon dioxide is very high and there is no ventilation. [11]

Coach’s claim

A feeling of faintness can come from a lack of fresh air. [7]

Ventilating the training space

Coach’s claim

Keep airflow going indoors to keep the air clean and oxygenated, especially when there is illness or vulnerability. Open-air ventilation is very important for training indoors. [4] [10]

Breathing during hard training

During intense training, inhale through the nose and exhale through the mouth, breathing deeply. If the room has no air, open a window. [8]

Checking the air

Coach’s claim

A carbon dioxide monitor reading of 500-600 is ideal or nearly normal. A reading around 1500 leaves only about half of your mental capacity usable. [10]

Coach’s experience

In his own training, stuffy, oppressive air made intense training feel very heavy and bothered him. Cooler morning and evening conditions caused no problem. [2]

Sources

1. 2024-02-05, 862.8-870.4s

Workout: workout:2024-02-05

Passage: passage:2024-02-05:000341-000342

2. 2024-11-04, 315.5-337.4s

Workout: workout:2024-11-04

Passage: passage:2024-11-04:000101-000106

3. 2024-11-26, 3443.2-3479.4s

Workout: workout:2024-11-26

Passage: passage:2024-11-26:000929-000938

4. 2025-10-10, 2590.3-2605.7s

Workout: workout:2025-10-10

Passage: passage:2025-10-10:000572-000577

5. 2025-12-28, 3769.9-3775.8s

Workout: workout:2025-12-28

Passage: passage:2025-12-28:001275-001277

6. 2026-01-21, 2493.1-2510.1s

Workout: workout:2026-01-21-meeting

Passage: passage:2026-01-21-meeting:000639-000645

7. 2026-02-05, 1880.2-1922.0s

Workout: workout:2026-02-05

Passage: passage:2026-02-05:000535-000546

8. 2026-02-14, 4110.7-4121.9s

Workout: workout:2026-02-14

Passage: passage:2026-02-14:001163-001168

9. 2026-06-06, 2918.7-2934.0s

Workout: workout:2026-06-06

Passage: passage:2026-06-06:000902-000908

10. 2026-06-06, 3041.0-3067.4s

Workout: workout:2026-06-06

Passage: passage:2026-06-06:000933-000941

11. 2026-08-02, 3720.6-3733.8s

Workout: workout:2026-08-02

Passage: passage:2026-08-02:001108-001111