McMorries Rebecca M, Joubert Dustin P, Jones Eric J, Faries Mark D
Department of Kinesiology and Health Science, Stephen F. Austin State University, Nacogdoches, TX, USA.
Family and Community Health, Texas A&M AgriLife Extension Service, College Station, TX, USA.
Int J Exerc Sci. 2019 Jan 1;12(2):221-232. doi: 10.70252/LOED6863. eCollection 2019.
The lactate threshold is considered a key marker of endurance exercise performance and identification of this threshold is important in writing an exercise training program. Unfortunately, assessment of the lactate threshold has traditionally required venous or capillary blood samples and a specialized meter to assess blood lactate concentrations. Recently, a consumer grade, non-invasive device was developed to determine muscle oxygenation and estimate the lactate threshold.
The aim of this study was to assess the validity of a noninvasive lactate threshold device (NID) to determine lactate threshold heart rate (LTHR).
Twenty-one recreational athletes (14 females, 39 ± 7 years, 29.1 ± 5.2% fat, 37.8 ± 6.0 ml·kg·min; 7 males, 42 ± 9 years, 16.8 ± 2.2% fat, 45.9 ± 6.4 ml·kg·min) completed a personalized graded exercise test on a treadmill. All participants wore the NID and blood lactate samples were taken at the end of 3-minute stages. LTHR was then calculated using two traditional methods (4 mmol/L and >1 mmol/L increase) and compared against the same heart rate values calculated by the NID.
No significant differences (p = .87) were found in LTHR between the NID and the traditional lactate methods (NID: 167 ± 9 bpm, 4 mmol/L: 167 ± 12 bpm, >1 mmol/L: 167 ± 12 bpm).
This study provides preliminary support for the validity of the NID for estimation of LTHR.
乳酸阈值被认为是耐力运动表现的关键指标，确定该阈值对于制定运动训练计划很重要。不幸的是，传统上评估乳酸阈值需要采集静脉或毛细血管血样，并使用专门的仪器来测定血乳酸浓度。最近，开发了一种消费级的非侵入性设备来测定肌肉氧合并估算乳酸阈值。
本研究的目的是评估一种非侵入性乳酸阈值设备（NID）测定乳酸阈值心率（LTHR）的有效性。
21名休闲运动员（14名女性，年龄39±7岁，体脂率29.1±5.2%，摄氧量37.8±6.0 ml·kg·min；7名男性，年龄42±9岁，体脂率16.8±2.2%，摄氧量45.9±6.4 ml·kg·min）在跑步机上完成了个性化的分级运动测试。所有参与者均佩戴NID，并在3分钟阶段结束时采集血乳酸样本。然后使用两种传统方法（4 mmol/L和升高>1 mmol/L）计算LTHR，并与NID计算的相同心率值进行比较。
NID与传统乳酸测定方法之间的LTHR无显著差异（p = 0.87）（NID：167±9次/分钟，4 mmol/L：167±12次/分钟，>1 mmol/L：167±12次/分钟）。
本研究为NID估算LTHR的有效性提供了初步支持。
