An investigation was carried out to measure the cardiac output of an athlete before, during, and after a period of intense exercise on a stationary bicycle. The results are shown in Table 1.
Table 1
| Time (minutes) | Cardiac output (dm3 min−1\text{dm}^3\text{ min}^{-1}dm3 min−1) |
|---|---|
| 0 | 5.0 |
| 2 | 5.0 |
| 4 | 15.5 |
| 6 | 24.0 |
| 8 | 24.0 |
| 10 | 8.5 |
Explain the trend shown in Table 1 from 2 minutes to 6 minutes.