Building The Aerobic Engine
Test week is in full swing and today we face a 2400m Run for time. I know its a silly distance, but the truth is, the 2400m Run is a standard test designed by exercise scientists to test Aerobic Efficiency.
Why is this important?
It is important because all maximal effort activity past 45 secs is primarily fueled by the Aerobic system (Oxygen). Since all benchmark WODs or Open WODs are longer than 45 secs, the aerobic system plays an extremely important role for athletes trying to extend their work capacity in CrossFit.
Exercise Science
Our body’s fuel is ATP (Adenosine Triphosphate). For muscles to contract you need ATP present in the muscle cells. Depending on the duration of the activity, ATP can be supplied in 3 ways.
- Creatine Phosphate (Alactic) System (ATP stored in Muscle Cell at rest)
- Anaerobic System (ATP supplied without Oxygen)
- Aerobic System (ATP supplied with Oxygen)
Each system regenerates ATP depending on exercise duration.
- Alactic System 0-15 secs
- Anaerobic System 15-45 secs
- Aerobic System 45sec – 2 Hours +
Think of it as…
- Alactic = Lifting and Sprinting
- Anaerobic = Row Sprints, 1 min Burpee Challenge, etc.
- Aerobic = 2 mile Time Trial, or Longer WOD’s
VO2 Max
When testing Aerobic efficiency we will get a VO2 Max number. VO2 is Volume of Oxygen Max. The Higher the VO2 the more efficient you are utilizing your aerobic system. For example, soccer player David Beckham has a score of 67.6. Former cyclist Lance Armstrong 84, and the average American has a score of 35. After today you will know your score. Below is a chart with times and the corresponding VO2 score. After your 2400m Time Trial, find your score and write it down. If we really want to expand our limits. We must always improve our strength numbers in the weightroom and VO2 Max.
Estimated Maximal Oxygen Uptake(VO2max) for the 1.5-Mile Run Test
Time |
VO2 |
Time |
VO2 |
Time |
VO2 |
6:10 |
80.0 |
10:30 |
48.6 |
14:50 |
34.0 |
6:20 |
79.0 |
10:40 |
48.0 |
15:00 |
33.6 |
6:30 |
77.9 |
10:50 |
47.4 |
15:10 |
33.1 |
6:40 |
76.7 |
11:00 |
46.6 |
15:20 |
32.7 |
6:50 |
75.5 |
11:10 |
45.8 |
15:30 |
32.2 |
7:00 |
74.0 |
11:20 |
45.1 |
15:40 |
31.8 |
7:10 |
72.6 |
11:30 |
44.4 |
15:50 |
31.4 |
7:20 |
71.3 |
11:40 |
43.7 |
16:00 |
30.9 |
7:30 |
69.9 |
11:50 |
43.2 |
16:10 |
30.5 |
7:40 |
68.3 |
12:00 |
42.3 |
16:20 |
30.2 |
7:50 |
66.8 |
12:10 |
41.7 |
16:30 |
29.8 |
8:00 |
65.2 |
12:20 |
41.0 |
16:40 |
29.5 |
8:10 |
63.9 |
12:30 |
40.4 |
16:50 |
29.1 |
8:20 |
62.5 |
12:40 |
39.8 |
17:00 |
28.9 |
8:30 |
61.2 |
12:50 |
39.2 |
17:10 |
28.5 |
8:40 |
60.2 |
13:00 |
38.6 |
17:20 |
28.3 |
8:50 |
59.1 |
13:10 |
38.1 |
17:30 |
28.0 |
9:00 |
58.1 |
13:20 |
37.8 |
17:40 |
27.7 |
9:10 |
56.9 |
13:30 |
37.2 |
17:50 |
27.4 |
9:20 |
55.9 |
13:40 |
36.8 |
18:00 |
27.1 |
9:30 |
54.7 |
13:50 |
36.3 |
18:10 |
26.8 |
9:40 |
53.5 |
14:00 |
35.9 |
18:20 |
26.6 |
9:50 |
52.3 |
14:10 |
35.5 |
18:30 |
26.3 |
10:00 |
51.1 |
14:20 |
35.1 |
18:40 |
26.0 |
10:10 |
50.4 |
14:30 |
34.7 |
18:50 |
25.7 |
10:20 |
49.5 |
14:40 |
34.3 |
19:00 |
25.4 |
-Coach Aaron