Image photoplethysmography can realize low-cost and easy-to-operate non-contact heart rate detection from the facial video, and effectively overcome the limitations of traditional contact method in daily vital sign mo...Image photoplethysmography can realize low-cost and easy-to-operate non-contact heart rate detection from the facial video, and effectively overcome the limitations of traditional contact method in daily vital sign monitoring. However, it is hard to obtain more accurate heart rate detection values under the conditions of subject’s facial movement, weak ambient light intensity and long detection distance, etc. In this article, a non-contact heart rate detection method based on face tracking is proposed, which can effectively improve the accuracy of non-contact heart rate detection method in practical application. The corner tracker algorithm is used to track the human face to reduce the motion artifact caused by the movement of the subject’s face and enhance the use value of the signal. And the maximum ratio combining algorithm is used to weight the pixel space pulse wave signal in the facial region of interest to improve the pulse wave extraction accuracy. We analyzed the facial images collected under different experimental distances and action states. This proposed method significantly reduces the error rate compared with the independent component analysis method. After theoretical analysis and experimental verification, this method effectively reduces the error rate under different experimental variables and has good consistency with the heart rate value collected by the medical physiological vest. This method will help to improve the accuracy of non-contact heart rate detection in complex environments.展开更多
Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacit...Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacity of elite Congolese karate athletes, as well as their haemodynamic and blood lactate concentrations responses changes during Ruffier test and stimulated competition. Methods: Twelve karate athletes (6 seniors and 6 juniors) took part in the study. These karate athletes were selected within the national karate teams (senior and junior) of Congo-Brazzaville. Anthropometric, bioenergetic and haemodynamic (HR, SBP, DBP) parameters and blood lactate [La] concentrations were measured at rest, immediately after the end of Ruffier test and each fight (n = 3). Results: Peak aerobic power (PAP) and maximum oxygen uptake (VO2 max) values averaged 437 ± 23 watts and 57.61 ± 2.2 ml/kg/mn, values varying as function as age division (senior vs junior). The recovery index was 5.4 ± 3.4 for juniors and 6.8 ± 3.2 for seniors. SBP, HR and [La] concentrations increased significantly during fights, compared to the resting values. HRmax was 182.3 ± 1.6 bpm (89% theoretical HRmax) for seniors and 182.0 ± 13.5 bpm (86% theoretical HRmax) for juniors. Peak [La] concentrations were 10.3 ± 1.5 mmol/l for seniors and 10.8 ± 1.2 mmol/l for juniors. Conclusion: Congolese karate athletes call upon high levels of the anaerobic and aerobic capacities. The karate training program in Congo should emphasize more gold improvising lower body anaerobic power and endurance.展开更多
The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calc...The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calculating H Rmaxwas the most suitable for use with the Karvonen formula. First, two kinds of experiments involving an ergometer were performed: an all-in-one-day experiment that tested eight pedaling loads in one day, and a one-load-per-day experiment that tested one load per day for eight days.A comparison of the data on 7 subjects showed that the all-in-one-day type of experiment was better for assessing H Rmaxformulas,at least for the load levels tested in our experiments. A statistical analysis of the experimental data on 47 subjects showed two of the H Rmaxformulas to be suitable for use in the Karvonen formula to estimate exercise intensity for males in their 20 s. In addition, the physical characteristics of a person having the greatest impact on exercise intensity were determined.展开更多
目的 探讨冠心病患者血小板聚集功能在不同临床分型、不同冠脉病变支数水平变化及与同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)相关性。方法 回顾性分析唐山市第三医院首次确诊的冠心病患者152例,按照冠状动脉造影结果将冠心病患者分为...目的 探讨冠心病患者血小板聚集功能在不同临床分型、不同冠脉病变支数水平变化及与同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)相关性。方法 回顾性分析唐山市第三医院首次确诊的冠心病患者152例,按照冠状动脉造影结果将冠心病患者分为单支病变组和多支病变组;再按应激状态分为急性冠脉综合征(ACS)组和非ACS组,分析以二磷酸腺苷(ADP)和花生四烯酸(AA)为诱导剂的血小板聚集功能在各组间的变化,探讨其与Hcy、hs-CRP的相关性。结果 单支病变组和多支病变组以ADP和AA为诱导剂的最大血小板聚集率比较差异均无统计学意义( P >0.05);ACS组与非ACS组以ADP和AA为诱导剂的最大血小板聚集率比较差异均有统计学意义( P <0.05);冠心病患者hs-CRP、Hcy水平与AA、ADP诱导的最大血小板聚集率呈显著的正相关( r 1=0.29、0.33;r 2=0.37、0.34, P <0.05)。结论 最大血小板聚集率在ACS、非ACS患者中呈现不同的变化且与hs-CRP、Hcy密切相关,对冠心病的诊断、治疗、危险评估有一定的参考价值。展开更多
文摘Image photoplethysmography can realize low-cost and easy-to-operate non-contact heart rate detection from the facial video, and effectively overcome the limitations of traditional contact method in daily vital sign monitoring. However, it is hard to obtain more accurate heart rate detection values under the conditions of subject’s facial movement, weak ambient light intensity and long detection distance, etc. In this article, a non-contact heart rate detection method based on face tracking is proposed, which can effectively improve the accuracy of non-contact heart rate detection method in practical application. The corner tracker algorithm is used to track the human face to reduce the motion artifact caused by the movement of the subject’s face and enhance the use value of the signal. And the maximum ratio combining algorithm is used to weight the pixel space pulse wave signal in the facial region of interest to improve the pulse wave extraction accuracy. We analyzed the facial images collected under different experimental distances and action states. This proposed method significantly reduces the error rate compared with the independent component analysis method. After theoretical analysis and experimental verification, this method effectively reduces the error rate under different experimental variables and has good consistency with the heart rate value collected by the medical physiological vest. This method will help to improve the accuracy of non-contact heart rate detection in complex environments.
文摘Background: Rare are the studies which treated the effect of training and successive fights of karate on haemodynamic and blood lactate concentrations responses. Objectives: To evaluate and analyze the aerobic capacity of elite Congolese karate athletes, as well as their haemodynamic and blood lactate concentrations responses changes during Ruffier test and stimulated competition. Methods: Twelve karate athletes (6 seniors and 6 juniors) took part in the study. These karate athletes were selected within the national karate teams (senior and junior) of Congo-Brazzaville. Anthropometric, bioenergetic and haemodynamic (HR, SBP, DBP) parameters and blood lactate [La] concentrations were measured at rest, immediately after the end of Ruffier test and each fight (n = 3). Results: Peak aerobic power (PAP) and maximum oxygen uptake (VO2 max) values averaged 437 ± 23 watts and 57.61 ± 2.2 ml/kg/mn, values varying as function as age division (senior vs junior). The recovery index was 5.4 ± 3.4 for juniors and 6.8 ± 3.2 for seniors. SBP, HR and [La] concentrations increased significantly during fights, compared to the resting values. HRmax was 182.3 ± 1.6 bpm (89% theoretical HRmax) for seniors and 182.0 ± 13.5 bpm (86% theoretical HRmax) for juniors. Peak [La] concentrations were 10.3 ± 1.5 mmol/l for seniors and 10.8 ± 1.2 mmol/l for juniors. Conclusion: Congolese karate athletes call upon high levels of the anaerobic and aerobic capacities. The karate training program in Congo should emphasize more gold improvising lower body anaerobic power and endurance.
基金supported by Health Science Center Foundation,Japan
文摘The Karvonen formula, which is widely used to estimate exercise intensity, contains maximum heart rate, H Rmax, as a variable. This study employed pedaling experiments to assess which of the proposed formulas for calculating H Rmaxwas the most suitable for use with the Karvonen formula. First, two kinds of experiments involving an ergometer were performed: an all-in-one-day experiment that tested eight pedaling loads in one day, and a one-load-per-day experiment that tested one load per day for eight days.A comparison of the data on 7 subjects showed that the all-in-one-day type of experiment was better for assessing H Rmaxformulas,at least for the load levels tested in our experiments. A statistical analysis of the experimental data on 47 subjects showed two of the H Rmaxformulas to be suitable for use in the Karvonen formula to estimate exercise intensity for males in their 20 s. In addition, the physical characteristics of a person having the greatest impact on exercise intensity were determined.
文摘目的 探讨冠心病患者血小板聚集功能在不同临床分型、不同冠脉病变支数水平变化及与同型半胱氨酸(Hcy)、超敏C反应蛋白(hs-CRP)相关性。方法 回顾性分析唐山市第三医院首次确诊的冠心病患者152例,按照冠状动脉造影结果将冠心病患者分为单支病变组和多支病变组;再按应激状态分为急性冠脉综合征(ACS)组和非ACS组,分析以二磷酸腺苷(ADP)和花生四烯酸(AA)为诱导剂的血小板聚集功能在各组间的变化,探讨其与Hcy、hs-CRP的相关性。结果 单支病变组和多支病变组以ADP和AA为诱导剂的最大血小板聚集率比较差异均无统计学意义( P >0.05);ACS组与非ACS组以ADP和AA为诱导剂的最大血小板聚集率比较差异均有统计学意义( P <0.05);冠心病患者hs-CRP、Hcy水平与AA、ADP诱导的最大血小板聚集率呈显著的正相关( r 1=0.29、0.33;r 2=0.37、0.34, P <0.05)。结论 最大血小板聚集率在ACS、非ACS患者中呈现不同的变化且与hs-CRP、Hcy密切相关,对冠心病的诊断、治疗、危险评估有一定的参考价值。
