Lactate Scout+ (PRODUCT DISCONTINUED)

During endurance exercises such as long-distance running and cycling, when the demand for energy is high, lactate is produced faster than the ability of the tissues to remove it. As a result lactate concentration in the blood begins to rise.

The use of a lactate analyzer helps coaches and athletes to determine optimum training programs, define training zones, and avoid inefficient training exercises.

In fitness, sports, and cardio-rehabilitation measuring lactate is supportive to define training intensities for maximum fat catabolism, increases in endurance, and avoid critical over-exhaustion.

Lactate is produced when the muscles use carbohydrates to create energy for exercise. The underlying metabolic process is the glycolysis. It happens continuously but increases when energy demand is high for a prolonged period of time and availability of oxygen to the cells is limited.

Increased glycolysis produces hydrogen ions and lactate, and it's the hydrogen ions that cause pain, sore muscles, cramps and fatigue. The body protects itself by telling you: "I can't do this anymore".

Regular endurance sports should only take place within the respective 'lactate steady-state' - a well-balanced relationship between lactate production and elimination.

Lac [blood] = Lac [produced] ­ Lac [eliminated ]

With higher exercise intensity the lactate level in the blood reaches the anaerobic threshold or the onset of rapid blood lactate accumulation. This point can be determined in step tests with increasing training intensity in defined intervals e.g. on a tread-mill, bicycle or in a field test. The higher the level of effort is when the rise of lactate indicates the anaerobic threshold the better is the performance status of the athlete.

Intense training teaches the body to use lactate as a source of fuel on a par with the carbohydrates stored in muscle tissue and the sugar in blood. Athletes increase their lactate threshold by training which means their blood lactate increases later and at higher intensities.

There are many uses of lactate in healthcare. Some of these are well established, for example lactate measurement in fitness and cardio training. As a world-leader in lactate, EKF has been closely involved in recently developed applications of lactate in obstetric medicine. On this page you can find out more about the increasingly important role of lactate in healthcare.

Lactate and obstetrics

During birth a number of potential complications for mother and child may occur. These complications can lead to decreased oxygenation of the fetus and/or prolonged pain and injury of the mother. Monitoring mother and fetus closely provides decisions tools for an efficient and safe process of birth. 

Cord blood lactate (CBL)

Umbilical cord blood analysis, including lactate measurement, provides an indication of the acid–base balance of the infant at birth.  It is recommended in all high‐risk deliveries and, in some countries, is performed routinely after all deliveries. Cord blood lactate (CBL) has a predictive value for perinatal outcome and elevated lactate levels alert clinicians to undertake immediate intervention.

Fetal scalp lactate (FSL)

Monitoring fetal heart rate with a cardiotocograph (CTG) often indicates fetal distress but most of those neonates are not hypoxic at birth. A diagnostic test is required to confirm abnormal CTG values. In 1962 Saling et al / first described the use of pH measurement from fetal scalp during delivery as an indicator of hypoxia.

Measuring pH became a widely used clinical practice based on their findings. This approach is complicated by the need to collect a significant amount of blood (30-50 μl). This has led to reported sampling failure rates of 11-20%.

The alternative to this approach, fetal scalp lactate (FSL), is a simpler test which requires only a low volume of blood. Studies report significantly fewer failures in sampling with lactate analysis and no differences in short term neonatal outcome.

Emergency medicine and critical care

There are a number of causes for hyperlactatemia in critical ill patients. Sepsis, shock and trauma are the most common and serious ones. Pre-hospital measurements of lactate have been shown to improve the prediction of mortality, surgery and multi-organ failure.

Lactate and cardio training, weight reduction and fitness

Regular endurance exercise has many benefits for health and well-being. It has been proven to lower systolic and diastolic blood pressure, improve insulin sensitivity and lower HbA1c levels, lower triglycerides and increase HDL-cholesterol. Regular power exercise, meanwhile, can increase insulin sensitivity.The maximal fat oxidation rate is reached under long term aerobic conditions because this is when predominantly free fatty acids are used as the energy source. In contrast, under anaerobic conditions mainly carbohydrates are used for generating energy.

The measurement of lactate during step tests reveals the shift from aerobic (oxygen dependent) to complementary anaerobic (non-oxygen dependent) metabolism.  The knowledge of this ‘anaerobic threshold’ can be used for the definition of training intensities and conditions to achieve optimal fitness and weight reduction.

Furthermore, lactate testing can support a secure and efficient training avoiding critical over-exhaustion.

General Safety note

Lactate Scout+ can be used as a monitoring or screening tool by qualified staff in various medical settings. The test results should only be used as a support for clinical decision making. As with any chemical reaction, the user must be aware of the potential effect on the result due to unknown interference from medication or endogenous substances. All patient results must be evaluated considering the total clinical status of the patient. Any decision for medical use of the device must be taken by the responsible clinician based on the specification of the device and local regulatory guidelines.

Lactate testing in the veterinary field works in a very similar way to the human application. Lactate measurements are carried out to determine the performance of racing animals like horses or dogs, to monitor organ dysfunction, inflammatory processes in critically ill animals or in a multitude of basic research applications.

EKF's lactate analyzers, Biosen and Lactate Scout+, meet the demands of veterinary. A wide measurement range covers the typical values of different species. E.g. racing horses have a very high 'maxlass' (being the highest stable or balanced lactate level during exercise) of above 20 mmol/L, a level at which both devices deliver accurate results.