January 10, 2011, 02:01PM PT in Exam Preparation Blog |
Understanding VT1 and VT2
Ventilatory threshold is introduced in the ACE 4th edition Personal Trainer Manual as a way to measure a client’s intensity during exercise. Vt1 and VT2 play a role in the ACE Integrated Fitness Training Model, specifically as transition points between zones 1, 2 and 3 of cardiovascular training.
What is a ventilatory threshold? Well, according to the glossary at the back of the Essentials manual, the VT is the ‘point of transition between predominantly aerobic energy production to anaerobic energy production.’ And if you want to get specific…then the first ventilatory threshold is ‘the intensity at which ventilation starts to increase in a non-linear fashion’ and the second ventilatory threshold is ‘the point at which high-intensity exercise can no longer be sustained due to an accumulation of lactate’.
Make sense? I admit it can be confusing if you are just looking at the definitions. The short version is that VT1 and VT2 provide a convenient way to divide intensity into training zones when looking at cardiovascular exercise. Zone 1 (relatively easy exercise) reflects heart rates below VT1. Zone 2 represents heart rates from VT1 to just below VT2. Zone 3 represents heart rates at or above VT2.
Below is a diagram of how the three zone setup of the Integrated Fitness Training Model relates to VT1 and VT2
But how do we measure VT1 and VT2? Research has found that the Talk Test (as described on pgs 382-383 in the Personal Trainer Manual) provides an accurate measure of the body’s response to increasing intensity. Where before we relied solely on percentage of heart rate, now we have discovered that talk test relates very well to similar intensities.
Below VT1: you can speak comfortably, recite the alphabet etc.
At VT1: you can no longer speak comfortably; it requires some effort at this point
Above VT1/Below VT2: speaking is possible, but not really comfortable, you can’t recite the entire alphabet with ease at this point
At VT2: Speaking is no longer possible with the exception of one or two word statements, chances are you are not going to be able to exercise much longer above this point
For a live example of how VT1 and VT2 works with the 3 zone IFT model, check out the ACE YouTube video featuring Todd and Marion:
Understanding VT1 and VT2 is a critical part of the Integrated Fitness Training Model. The information above should get you started. If you have questions, call up an Education Consultant at 1-888-825-3636 x782.