Lactate Threshold Test with Senzimes On-Line Lactate Monitoring
The lactate threshold (LT) is the exercise intensity at which lactate starts to accumulate in the blood. This happens when lactate is produced faster than it can be metabolized in the muscle. When exercising at or below the LT, any lactate produced by the muscles is removed by the body without it building up.[i]
The LT is a useful measure for deciding exercise intensity for training and racing in endurance sports (e.g. long distance running, cycling, rowing, swimming and cross country skiing), but varies between individuals and can be increased with training[ii],[iii]. The aim of this test is to assess the aerobic endurance performance with OneSenz principle. To be able to do so a comparison is made with a handled point-of-care lactate analyzer, Lactate Stout. In the future, OneSenz monitoring will help predicting endurance capacity and performance potentials by determining lactate threshold values.
(see picture in the pdf version)
In this study, lactate threshold test was performed on an exercise bike at Mantra Sport in Uppsala and is a so-called sub-maximal test for determining the lactate threshold. The test included a 4 minutes increasing intensity for each interval. The OneSenz on-line lactate analyzer, (Senzime AB (publ)) was connected with a microdialysis catheter via a standard peripheral vein catheter (PVK) to the forearm. A new value was presented every second minute. To assess the reliability and accuracy of our method, off-line samples were taken as a reference from a second PVK on the opposite arm and were analyzed in a handheld point-of-care lactate analyzer. The heartrate was monitored with a heart rate band around the chest.
The results of the first on-line lactate threshold test with OneSenz showed an excellent agreement compared with the handheld lactate analyzer (fig 1).
(see figure in the pdf version)
Figure 1. Comparison of blood lactate concentration of OneSenz and reference lactate analyzer and heart rate at different intensity levels when cycling
As an advantage, using OneSenz compared to a handheld lactate analyzer, there is no need for multiple venipunctures for lactate sampling and more lactate values are obtained. In this way, the participants can be free of any disturbances and mainly focus on performing a good reliable endurance test.
Acknowledgement
We would like to thank Fredrik Swahn for the opportunity to perform this first test at Mantra Sport in Uppsala!
For more information please contact
Rianne Lundqvist Waninge , Application Scientist, Senzime AB, Uppsala, Sweden
Email: rianne.waninge@senzime.com www.senzime.com
Tel: +46735449974
[i] Brooks GA, Anaerobic threshold: review of the concept and directions for future research, Medicine and Science in Sports and Exercise, 1985
[ii] Faude et al. Lactate Threshold Concepts, How valid are They? Sports med, 2009; 39
[iii] Billat Veronique, Use of Blood Lactate Measurements for Prediction of Exercise Perdormance and for Control of Training, Sport Medicine, Volume 22, Issue 3, 1996