VO2 Max/Lactate-Ventilatory Threshold Testing

VO2 max has classically been described at the best indicator of cardiopulmonary fitness. In short the “VO2 max” or “VO2 peak” is the greatest amount of oxygen able to be exchanged during a maximal exercise event. VO2 max naturally increases with exercise training. In the endurance athlete, however, the lactate or ventilatory threshold may be a more important data point for performance improvement. During a VO2 max test, O2 consumption and CO2 production will increase together until the exercise intensity reaches the point where CO2 production increases due to the entrance of lactic acid into the bloodstream as intensity increases. This lactate acid will be buffered by sodium bicarbonate in the bloodstream producing excess CO2 which must be exhaled. During a VO2 max test, the CO2 production will increase without an increase in O2 consumption. This point is termed the lactate threshold (LT) or ventilatory threshold (VT). Once the LT/VT has been crossed fatigue will be “on the clock” as the body moves toward exhaustion.

With knowledge of the LT the athlete/coach is able to help determine the correct training intensities. With training near the LT, the athlete will typically see a “pushback” of the LT that allows for faster speeds or higher power outputs without reaching the LT.

How a VO2 max/Lactate Threshold test is conducted:

  • 1. Client should fast for 4 hours before the test. You don’t want to max exert yourself on a full stomach.
  • 2. Client will wear a HR monitor and VO2 facemask (over the nose and mouth). The mask is connected to the metabolic cart via a collection tube.
  • 3. Treadmill or cycling can be utilized. If treadmill running, familiarize yourself with running on a treadmill. If cycling, bring your own bike (we utilize a Computrainer Lab system that will customize your testing to your bike).

Are you eligible for a VO2 max test?
To conduct any maximal exercise test at our laboratory certain health factors are required to safely conduct the test.

  • 1. Age < 45 for males, < 55 for females
  • 2. No pre-existing medical condition involving cardiac event, stroke, or cancer-related treatment.
  • 3. No family history of sudden cardiac death (before age 55) in immediate family.
  • 4. Pregnancy
  • 5. Any current cardiac conditions (HTN, arrythmias). Smoking, High cholesterol, obesity, or sedentary lifestyle.

To schedule any testing at the PPL or if you have any questions concerning your eligibility for a VO2 max/LT test please contact Dr. Luke Heusel, PT,OCS @ 706-922-6550 0r email: lheusel@live.com

Current Lab schedule for testing is Wednesday mornings 8-12 a.m and other days/times as needed by our clients.