Lactate Threshold

What a lactate threshold test can tell you:

Your lactate threshold (LT) is the point at which your body’s lactate clearance begins to fall behind its lactate production, and there is accumulation of lactate in the blood. This increase in lactate production occurs when the body cannot take in enough oxygen to adequately supply tissues for metabolism during activity. Physiological factors that contribute to oxygen distribution will have an effect on LT. As result, intense aerobic training will result in improvements to LT. This measure is usually expressed as an intensity such as speed, pace, or power output. Determination of your lactate threshold can help guide training practices for improved performance by providing a benchmark intensity for stressing your body’s lactate system. The higher your lactate threshold, the harder you can train before you begin to fatigue.

What to Expect:

For a lactate threshold test, you should arrive to our facilities in appropriate active wear and having had only a light meal at least 2 hours prior. After you have been briefed by a technician on protocol you will be implemented with a heart rate monitor that is worn around the rib cage. You will have the option to select either a treadmill or cycle ergometer protocol depending on your preference as to which is more applicable to your training habits. Both tests will involve graded exercise to near maximal effort. Depending on your age and fitness level a warm-up intensity and increment load will be selected. After your warm up, each stage will be 3-4 minutes long. At the end of each stage, intensity will be increased and a blood sample will be taken from your earlobe using a lancet and blood lactate meter to measure lactate concentration. When you can no longer maintain your pace, the test will end. A testing session takes approximately 30 minutes.

How lactate threshold is calculated:

Your blood lactate concentration will be plotted on a graph against intensity. Lactate increase during activity remains fairly linear until your LT is reached at which point the slope of the plotted line will greatly increase, this is described as the inflection point. This inflection point will be used to determine your LT.