Expired air
Heart rate
Lactate
The First Threshold
This occurs at the exercise intensity at which blood lactate begins to rise above resting levels, termed Lactate Threshold (LT). It marks the shift from purely aerobic (low intensity) exercise to exercise that requires some anaerobic energy contribution (moderate intensity) that produces lactic acid. Exercising at an intensity at or below this threshold is relatively easy and you should be able to maintain it for a long duration (hours).
The Second Threshold
This occurs at a much higher intensity than the lactate threshold and represents the highest intensity that you can maintain for approximately 30 minutes. At intensities that are more difficult than this threshold, lactic acid would accumulate quickly to levels that would inhibit your ability to exercise and cause fatigue.
Maximal Oxygen Uptake (VO2 max)
Many athletes will have heard of this even if they have no background in sport science. This represents the largest volume of oxygen your body can use during exercise is known as maximal oxygen uptake (VO2 max) and indicates your aerobic potential.
This test also measures your peak aerobic power or running speed and the data can be used for setting training intensities. Your VO2 max is obtained by a separate small test which follows the blood lactate assessment.
VO2 Max Test
The test involves continuous exercise which gets more difficult every 1-minute. Initially, the exercise is easy and will gradually get harder using small increases in running speed and/or gradient (for treadmill protocols) or power output if being tested on a bike.
You will wear a mask over your nose and mouth throughout the test to allow respiration to be measured. This exercise test will last approximately 10-12 minutes and will be very tough towards the end.
