Study On Monitoring Physical Fatigue In Divers During Heliox Saturation Diving

Physical fitness of underwater immersion and high pressure is one of the key of the international diving medical research. Due to the limitations of environment or respirator, which affect the transport of oxygen and carbon dioxide, divers’ capacity is affected eventually, which will cause the corresponding physiological and psychological reactions, even the death. Exposed to high pressure, divers have to confront with the increasing gas density as well as the pressure. In such environment, how to monitor the divers’ capacity maintaining effective is the key to evaluating the practical technique. Analyze 6 time points of the 18 divers’ heart rate (HR) and the scores of rating of perceived exertion (RPE) scale were recorded:T1. the morning that the subjects just woke up without any physical activities before the subjects entered the chamber; T2. the first day morning that the subjects were exposed to 1.1MPa; T3. the peak of the subjects physical exercise load test under 1.1 MPa, the second point and the third were on the same day; T4. the morning of the second day under 1.1 MPa; T5. the morning of the first day decompressed to 0.1 MPa out of the chamber; T6. the morning of the day a week ago out of the chamber. All the data of the text points were analyzed with paired-samples t-text. The correlation between HR and RPE was analyzed with Pearson correlation. Statistics showed that compressed to 1.1 MPa, the resting HR of subjects decreased. Compared with the resting HR, there was significant difference between T1 and T2 (P<0.05); there was the significant difference between T1 and T5 (P<0.05).7 days after postdive, the resting HR increased, compared with 1day after postdive. And there was the significant difference between T5 and T6 (P<0.05). Compared with the score of RPE scale recorded the day before entering the chamber, the scores of the first day exposed to 1.1 MPa, the second day exposed to 1.1 MPa and the day back to 0.1 MPa were significant increased (P<0.05). During the 100msw heliox saturation, with the variable physical work load, the trend of the changes of heart rate was still in accordance with the score of RPE scale. The relevant ratio of the both is 0.729 (P<0.01). Our study provides experimental evidence that the unite application of HR and RPE scale could monitor the physical fatigue of the divers during 100msw heliox saturation diving.