Lactate threshold by muscle electrical impedance in professional rowers

Abstract

Lactate threshold (LT) is one of the physiological parameters usually used in rowing sport training prescription because it indicates the transitions from aerobic to anaerobic metabolism. Assessment of LT is classically based on a series of values of blood lactate concentrations obtained during progressive exercise tests and thus has an invasive aspect. The feasibility of noninvasive LT estimative through bioelectrical impedance spectroscopy (BIS) data collected in thigh muscles during rowing ergometer exercise tests was investigated. Nineteen professional rowers, age 19 (mean) ± 4.8 (standard deviation) yr, height 187.3 ± 6.6 cm, body mass 83 ± 7.7 kg, and training experience of 7 ± 4 yr, were evaluated in a rowing ergometer progressive test with paired measures of blood lactate concentration and BIS in thigh muscles. Bioelectrical impedance data were obtained by using a bipolar method of spectroscopy based on the current response to a voltage step. An electrical model was used to interpret BIS data and to derive parameters that were investigated to estimate LT noninvasively. From the serial blood lactate measurements, LT was also determined through Dmax method (LT). The zero crossing of the second derivative of kinetic of the capacitance electrode (Ce), one of the BIS parameters, was used to estimate LT. The agreement between the LT estimates through BIS (LT) and through Dmax method (LT) was evaluated using Bland-Altman plots, leading to a mean difference between the estimates of just 0.07 W and a Pearson correlation coefficient r = 0.85. This result supports the utilization of the proposed method based on BIS parameters for estimating noninvasively the lactate threshold in rowing.

Decreased Blood Glucose and Lactate: Is a Useful Indicator of Recovery Ability in Athletes?

“…Clinical physicians and sports scientists have used lactate threshold (LT) tests for over fifty years because their application is considered extremely useful for recommendations on individual exercise intensity in cardiac patients and trained athletes [1,2]. Endurance athletes regularly undergo these tests in order to control individual exercise intensity during endurance training [1,[3][4][5][6]. Both respiratory and metabolic parameters are commonly utilized to identify the anaerobic threshold [1] and oxygen uptake (VO 2 ) during exercise performance influenced by the percentage of maximal oxygen uptake (VO 2max ) at LT.…”

Portable and Highly Versatile Impedance Meter for Very Low Frequency Measurements

“…Electrical Impedance Spectroscopy (EIS) is a non-invasive testing technique that has been extensively used and applied in several research fields. In medicine, for example, EIS (or BIS, Biological Impedance Spectroscopy) has proven to be an effective technique for non-invasive analyses and diagnosis of the healthy condition of subjects in a few medical fields [1][2][3][4][5][6][7][8] and furthermore, it seems to be appropriate for the characterization of the physicochemical properties of pharmaceutical materials [9] and of bacteria [10][11][12] and viruses [13,14].…”

Portable Knee Health Monitoring System by Impedance Spectroscopy Based on Audio-Board

“…Electrical impedance spectroscopy (EIS) has been widely used in biomedical applications for biological tissues' characterization [6], for disease identification, such as diabetes [7][8][9], for body composition analysis [10], for cardiac functions monitoring [11,12], for muscles' condition monitoring during sport activity [13], in dentistry [14] and in many other diagnostic fields.…”