Effect of Factors on Physiology Acclimatization of Construction Groups Entering Again into Plateau in Early Days

Purpose： To find out the relationship between duration of break, gender, age and the early physical conditions of the people who go to the Plateau again after the break. Means： The pre-work physical inspection data of 2528 people, who participated the construction on the Plateau （altitude 3080 m） during 2002 - 2004, and then returned during 2003 - 2005, were studied. Before the inspections, these people had been on the Plateau for 7 - 15 days to get them adaptable to the altitude conditions. These people were divided randomly into Long Break Group （break time≥90 d, n = 984） and Short Break Group （break time ≤60 d, n = 1544）. Then they were divided into sub-Groups based on gender and age. Statistical analysis was then done using SPSS 12.0 software. Resdts： （1）The means of sBP, dBP, HR, and Hb of the Long Break Group, after 7 - 15 days of adaptability period, were lower than that of Short Break Group; while SpO2 of Long Break Group was slightly higher than that of Short Break Group. （Mean p ≤0.001 ; The abnormal rates of ALT, BUN, BP of the Long Break Group were also significantly lower than that of Short Break Group （p 〈 0.05, or p 〈 0.001; （2）In the same group, or different groups, the BP, Hb of female sub-Group was better than male sub- Group（p 〈 0.05, or p 〈 0.001. The BP, ECG of 〈 40 y sub-Group is better than ≥40 y sub-Group（p 〈 0.05 or, p 〈 0.001. Conclusion： 3-month, or even longer break in winter has positive impacts on the early physical conditions of the constructors on the Plateau （esp. males over 40 years old）.