You may have heard the terms VO2 max and lactate threshold tossed around by athletes and coaches, but do you understand what they are, how they are measured and if they really matter? These articles help you make sense of the science.

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• VO2 Max, or maximal oxygen uptake, is one factor that can determine an athlete's capacity to perform sustained exercise and is linked to aerobic endurance.
• Lactate Threshold is one predictor of high intensity endurance performance that can be increased with training.
• Endurance refers to an athlete’s ability to sustain prolonged exercise for minutes, hours, or even days.