Bacteria grow most rapidly in the range of temperatures between 40 °F and 140 °F, doubling in number in as little as 20 minutes. This range of temperatures is often called the "Danger Zone.
- Karnoven heart rate Ratio Method
Advantages : Easy to do, cost friendly
Disadvantages : can only predict the amount of maximum oxygen intake
-Vo2max
Advantages : this test directly measures body oxygen consumption , the other tests only try to estimate
Disadvantages : Relativiely time consuming and high cost
