Blood Lactate Report
Blood lactate profile report
Trained -v- Untrained
The purpose of this test was to determine individuals, (trained and untrained) lactate threshold and subsequently interpret the results. This will allow for a comparison in how training affects the accumulation of blood lactate by using the results from the trained versus the untrained individual.
When the rate of lactate production exceeds the rate of uptake, lactic acid accumulates in the blood volume, and then we see the onset of blood lactate accumulation. This is what known as the traditional "Lactate Threshold" (LT)(1). This occurs when during exercise of an increasing intensity the lactate levels rise above that of resting levels.
When glucose is broken down it forms pyruvate. This pyruvate then gets converted to lactic acid via the enzyme lactate dehydrogenase. Lactate is formed from both aerobic and anaerobic glycolysis, however lactate does not so much accumulate in aerobic conditions as they body has the ability under these conditions to clear the lactate at the same time as it produces it. During anaerobic glycolysis, production rate is greater than clearance and lactic acid accumulates in the muscle tissue and can spill over into the bloodstream. This causes blood pH to increase and thus the blood acidity levels rise. Lactate is only harmful to exercise performance with the dissociation of the hydrogen ions from lactate causing the changes in pH levels. This shift in pH is thought to be a significant contributor to fatigue during exercise performance in many ways: (1) by inhibiting phosphofrucktokinase, and enzyme important for glycolysis; (2) by displacing calcium ions from troponin thus shutting down crossbridge cycling and decreasing the force of muscle contraction thus decreasing performance; (3) by stimulating local pain receptors; (4) by acting on the brain to cause pain and nausea; (5) and by interfering with hormone-sensitive lipase, an intra-cellular hormone that that is responsible
Trained -v- Untrained
The purpose of this test was to determine individuals, (trained and untrained) lactate threshold and subsequently interpret the results. This will allow for a comparison in how training affects the accumulation of blood lactate by using the results from the trained versus the untrained individual.
When the rate of lactate production exceeds the rate of uptake, lactic acid accumulates in the blood volume, and then we see the onset of blood lactate accumulation. This is what known as the traditional "Lactate Threshold" (LT)(1). This occurs when during exercise of an increasing intensity the lactate levels rise above that of resting levels.
When glucose is broken down it forms pyruvate. This pyruvate then gets converted to lactic acid via the enzyme lactate dehydrogenase. Lactate is formed from both aerobic and anaerobic glycolysis, however lactate does not so much accumulate in aerobic conditions as they body has the ability under these conditions to clear the lactate at the same time as it produces it. During anaerobic glycolysis, production rate is greater than clearance and lactic acid accumulates in the muscle tissue and can spill over into the bloodstream. This causes blood pH to increase and thus the blood acidity levels rise. Lactate is only harmful to exercise performance with the dissociation of the hydrogen ions from lactate causing the changes in pH levels. This shift in pH is thought to be a significant contributor to fatigue during exercise performance in many ways: (1) by inhibiting phosphofrucktokinase, and enzyme important for glycolysis; (2) by displacing calcium ions from troponin thus shutting down crossbridge cycling and decreasing the force of muscle contraction thus decreasing performance; (3) by stimulating local pain receptors; (4) by acting on the brain to cause pain and nausea; (5) and by interfering with hormone-sensitive lipase, an intra-cellular hormone that that is responsible
References: (1) Costill, D.L. (1986). Inside Running: Basics of sports physiology. Indianaopolis: Benchmark Press. (2) Germann, W.J. & Stanfield, C.L. (2002). Principles of Human physiology. Benjamin Cummings. (3) Wilmore, J.H., & Costill, D.L. (1999). Sport and Exercise physiology. 2nd edition. Human Kinetics. (4) Holloszy, J.O., & Coyle, E.F. (1984). Adaptations of skeletal muscleto endurance exercise and their metabolic consequences. Journal of Applied Physiology, 56.