Multimodal Physiological and Biomechanical Wearable Dataset for Non-Invasive Blood Lactate Estimation

This dataset contains multimodal physiological and biomechanical measurements collected from wearable devices during running experiments aimed at non-invasive estimation of blood lactate levels. The data include time-series and derived variables from heart rate monitors, respiratory sensors, and motion capture systems.The dataset columns are as follows:<b>id</b>: Subject identifier.<b>stage</b>: Experimental stage during the test.<b>speed (km/h)</b>: Running speed, with 0 indicating resting stage.<b>LT (mmol/L)</b>: Blood lactate threshold calculated by the Dmax method.<b>BLA (mmol/L)</b>: Blood lactate concentration.<b>BLAclass</b>: Exercise load classification based on lactate threshold, where 1 indicates high load (above LT) and 0 indicates low load (below LT).<b>max_hr (bpm)</b>: Maximum heart rate recorded.<b>LF (ms²)</b>: Low-frequency power (0.04–0.15 Hz) from heart rate variability (HRV) frequency domain analysis, reflecting sympathetic and parasympathetic interaction. Increased LF power is generally associated with sympathetic activation.<b>HF (ms²)</b>: High-frequency power (0.15–0.4 Hz) from HRV, primarily linked to parasympathetic activity related to respiratory sinus arrhythmia.<b>BF (breaths/min)</b>: Breathing frequency (breaths per minute).<b>BR (%)</b>: Minute ventilation, calculated as the current actual ventilation relative to maximal voluntary ventilation.<b>CI (L/min/m²)</b>: Cardiac index, i.e., cardiac output normalized by body surface area (m²).<b>EE (kcal/h)</b>: Energy expenditure in kilocalories per hour, representing metabolic energy produced from carbohydrates, fats, and proteins.<b>RER</b>: Respiratory exchange ratio, defined as the ratio of carbon dioxide output to oxygen uptake.<b>V'CO2 (L/min)</b>: Carbon dioxide output via alveolar ventilation (L/min).<b>V'E (L/min)</b>: Minute ventilation volume, equal to tidal volume multiplied by breathing frequency (L/min).<b>V'O2 (L/min)</b>: Oxygen uptake via alveolar ventilation (L/min).<b>VT (L)</b>: Tidal volume, the average volume of air inhaled or exhaled per breath at rest (L).<b>VGRF (BW)</b>: Vertical ground reaction force.<b>STEP</b>: Step frequency divided by speed.<b>SWING (s/(km/h))</b>: Average swing phase duration normalized by speed (s/km/h).<b>CONTACT (s/(km/h))</b>: Average foot contact time normalized by speed (s/km/h).<b>GAIT (s/(km/h))</b>: Average gait cycle duration normalized by speed (s/km/h).<b>CONGAIT (s/m)</b>: Ratio of contact time to gait cycle duration, normalized by speed.This comprehensive dataset supports research into physiological and biomechanical indicators related to blood lactate levels, enabling development of non-invasive monitoring methods during exercise.

本数据集收录了跑步实验中通过可穿戴设备采集的多模态生理与生物力学测量数据，其研究目标为实现血液乳酸水平的无创估测。该数据集包含源自心率监测仪（heart rate monitor）、呼吸传感器及动作捕捉系统的时序变量与衍生变量。
该数据集的字段如下：
<b>id</b>：受试者标识。
<b>stage</b>：测试过程中的实验阶段。
<b>speed (km/h)</b>：跑步速度，单位为千米每小时，取值0代表静息阶段。
<b>LT (mmol/L)</b>：通过Dmax法计算得到的血乳酸阈值（blood lactate threshold），单位为毫摩尔每升。
<b>BLA (mmol/L)</b>：血液乳酸浓度，单位为毫摩尔每升。
<b>BLAclass</b>：基于乳酸阈值划分的运动负荷等级，其中1代表高负荷（高于血乳酸阈值），0代表低负荷（低于血乳酸阈值）。
<b>max_hr (bpm)</b>：记录到的最大心率，单位为次每分钟（beats per minute, bpm）。
<b>LF (ms²)</b>：心率变异性（Heart Rate Variability, HRV）频域分析得到的低频功率（0.04–0.15 Hz），可反映交感与副交感神经系统的相互作用，低频功率升高通常与交感神经激活相关。
<b>HF (ms²)</b>：心率变异性（HRV）频域分析得到的高频功率（0.15–0.4 Hz），主要与呼吸性窦性心律不齐相关的副交感神经活动有关。
<b>BF (breaths/min)</b>：呼吸频率，单位为次每分钟，即每分钟呼吸次数。
<b>BR (%)</b>：分钟通气占比，以当前实际分钟通气量与最大自主通气量的比值计算，单位为百分比。
<b>CI (L/min/m²)</b>：心指数（cardiac index），即按体表面积（m²）归一化的心输出量，单位为升每分钟每平方米。
<b>EE (kcal/h)</b>：能量消耗，单位为千卡每小时，代表由碳水化合物、脂肪和蛋白质代谢产生的代谢能量。
<b>RER</b>：呼吸交换率（respiratory exchange ratio, RER），定义为二氧化碳排出量与氧气摄入量的比值。
<b>V'CO2 (L/min)</b>：肺泡通气产生的二氧化碳排出量，单位为升每分钟。
<b>V'E (L/min)</b>：分钟通气量，等于潮气量乘以呼吸频率，单位为升每分钟。
<b>V'O2 (L/min)</b>：肺泡通气的氧气摄入量，单位为升每分钟。
<b>VT (L)</b>：潮气量（tidal volume, VT），即静息状态下每次呼吸吸入或呼出的平均空气体积，单位为升。
<b>VGRF (BW)</b>：垂直地面反作用力（vertical ground reaction force, VGRF），以体重（body weight, BW）为单位。
<b>STEP</b>：步频与跑步速度的比值。
<b>SWING (s/(km/h))</b>：平均摆动相时长按跑步速度归一化后的结果，单位为秒每千米每小时。
<b>CONTACT (s/(km/h))</b>：平均足触地时长按跑步速度归一化后的结果，单位为秒每千米每小时。
<b>GAIT (s/(km/h))</b>：平均步态周期时长按跑步速度归一化后的结果，单位为秒每千米每小时。
<b>CONGAIT (s/m)</b>：触地时长与步态周期时长的比值，按跑步速度归一化后的结果，单位为秒每米。
本综合性数据集可为与血液乳酸水平相关的生理及生物力学指标研究提供支撑，助力运动过程中非侵入式监测方法的开发。