Department of Cardiovascular Medicine, Extreme Physiology Laboratory, Mayo Clinic, Rochester, MN.
Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN.
Chest. 2021 Oct;160(4):1377-1387. doi: 10.1016/j.chest.2021.04.041. Epub 2021 May 3.
Characterization of aerosol generation during exercise can inform the development of safety recommendations in the face of COVID-19.
Does exercise at various intensities produce aerosols in significant quantities?
In this experimental study, subjects were eight healthy volunteers (six men, two women) who were 20 to 63 years old. The 20-minute test protocol of 5 minutes rest, four 3-minute stages of exercise at 25%, 50%, 75%, and 100% of age-predicted heart rate reserve, and 3 minutes active recovery was performed in a clean, controlled environment. Aerosols were measured by four particle counters that were place to surround the subject.
Age averaged 41 ± 14 years. Peak heart rate was 173 ± 17 beat/min (97% predicted); peak maximal oxygen uptake was 33.9 ± 7.5 mL/kg/min; and peak respiratory exchange ratio was 1.22 ± 0.10. Maximal ventilation averaged 120 ± 23 L/min, while cumulative ventilation reached 990 ± 192 L. Concentrations increased exponentially from start to 20 minutes (geometric mean ± geometric SD particles/liter): Fluke >0.3 μm = 66 ± 1.8 → 1605 ± 3.8; 0.3-1.0 μm = 35 ± 2.2 → 1095 ± 4.6; Fluke 1.0-5.0 μm = 21 ± 2.0 → 358 ± 2.3; P-Trak anterior = 637 ± 2.3 → 5148 ± 3.0; P-Trak side = 708 ± 2.7 → 6844 ± 2.7; P-Track back = 519 ± 3.1 → 5853 ± 2.8. All increases were significant at a probability value of <.05. Exercise at or above 50% of predicted heart rate reserve showed statistically significant increases in aerosol concentration.
Our data suggest exercise testing is an aerosol-generating procedure and, by extension, other activities that involve exercise intensities at or above 50% of predicted heart rate reserve. Results can guide recommendations for safety of exercise testing and other indoor exercise activities.
在面对 COVID-19 时，对运动过程中气溶胶产生情况进行描述有助于制定安全建议。
不同强度的运动是否会产生大量气溶胶？
在这项实验研究中，研究对象为 8 名健康志愿者（6 名男性，2 名女性），年龄在 20 至 63 岁之间。该测试方案共 20 分钟，包括 5 分钟休息期和 4 个 3 分钟阶段：运动强度分别为预测心率储备的 25%、50%、75%和 100%，以及 3 分钟主动恢复期。在清洁、受控的环境中，通过放置在受试者周围的四个粒子计数器来测量气溶胶。
平均年龄为 41 ± 14 岁。最大心率为 173 ± 17 次/分钟（97%预测值）；最大摄氧量为 33.9 ± 7.5 mL/kg/min；最大呼吸交换率为 1.22 ± 0.10。最大通气量平均为 120 ± 23 L/min，而累计通气量达到 990 ± 192 L。从开始到 20 分钟，浓度呈指数增长（每升粒子的几何平均值±几何标准差）：Fluke >0.3 μm= 66 ± 1.8→1605 ± 3.8；0.3-1.0 μm= 35 ± 2.2→1095 ± 4.6；Fluke 1.0-5.0 μm= 21 ± 2.0→358 ± 2.3；P-Trak 前= 637 ± 2.3→5148 ± 3.0；P-Trak 侧= 708 ± 2.7→6844 ± 2.7；P-Track 后= 519 ± 3.1→5853 ± 2.8。所有增加均具有统计学意义（概率值<.05）。运动强度达到或超过预测心率储备的 50%时，气溶胶浓度呈统计学显著增加。
我们的数据表明，运动测试是一种产生气溶胶的过程，并且可以推断，其他涉及运动强度达到或超过预测心率储备的 50%的室内运动活动也是如此。结果可以为运动测试和其他室内运动活动的安全建议提供指导。
