NIRS Measurements with Elite Speed Skaters: Comparison Between the Ice Rink and the Laboratory

Abstract

Wearable, wireless near-infrared (NIR) spectrometers were used to compare changes in on-ice short-track skating race simulations over 1500m with a three-minute cycle ergometry test at constant power output (400W). The subjects were six male elite short-track speed skaters. Both protocols elicited a rapid desaturation (∆TSI%) in the muscle during early stages (initial 20s), however asymmetry between right and left legs was seen in ΔTSI% for the skating protocol, but not for cycling. Individual differences between skaters were present in both protocols. Notably, one individual who showed a relatively small TSI% change (-10.7%, group mean = -26.1%), showed a similarly small change during the cycling protocol (-5.8%, group mean = -14.3%). We conclude that NIRS-detected leg asymmetry is due to the specific demands of short-track speed skating. However, heterogeneity between individuals is not specific to the mode of exercise. Whether this is a result of genuine differences in physiology or a reflection of differences in the optical properties of the leg remains to be determined.

Performance Characteristics of Long-Track Speed Skaters: A Literature Review

“…However, a small knee angle also seems to lead to a reduced blood flow to the working muscles, resulting in a deoxygenation of these muscles [40]. This reduced blood flow in speed skating is supported by several studies involving (elite) short-track speed skaters [65][66][67][68]. The strong relationship between deoxygenated haemoglobin of the exercising quadriceps and lactate concentration, but not to the whole body VO 2, showed that the high lactate concentrations in (short-track) speed skating were caused by a reduced blood flow to the working muscles and not by the VO 2 of the athlete's whole body [65].…”

“…Moreover, they showed that the asymmetry was due to the specific demands of short-track speed skating and was not an intrinsic difference between the right and left quadriceps of the selected group [68]. Interestingly, although an asymmetry in muscle oxygenation during long-track speed skating was also reported, the difference in oxygenation between the legs was only the result of a difference in the initial desaturation between both legs directly after the start [43], while the short-track studies reported a similar initial desaturation in both legs followed by an asymmetry in deoxygenation during the race [66,67].…”

“…A future focus on experimental studies using new portable technologies (e.g. NIRS, which has already led to valuable insights into short-track speed skating [66][67][68]) may therefore provide relevant information about the influence of these interactions on processes of fatigue and performance in long-track speed skating. Also, psychological characteristics can be explored further, such as self-regulation in the context of training and pacing strategies, and the interaction of athletes with their environment.…”

“…The EFM, incorporating anthropometrical, technical, and physiological characteristics, provides insight into interactions between different variables. To complete the picture, more insight must be gained on psychological characteristics [63], the effects of the reduced blood flow to the working muscles in the skating position [43,44,[66][67][68], the increase of the push-off angle during long-distance races [36,37], or any interaction with the environment [53,74], which all were shown to be important for speed skating performance. To gain more insight into how all different characteristics affect each other, experimental studies aimed at understanding the relationships between the different speed skating characteristics.…”

Wearable Training-Monitoring Technology: Applications, Challenges, and Opportunities

“…Near-infrared spectroscopy (NIRS) is nowadays a wellaccepted technology to assess muscle oxygenation in vivo, and our previous research 18,19 together with studies conducted by others (for a review of this methodology see Ferrari et al 20 ) suggest that this technology could be implemented successfully in most sports, including aquatic sports. 21 While the market seems to be showing an increase in portable NIRS devices, only few present some form of validation to date.…”