Effect Of Altitude And Sub-altitude Training On Performance And Its Mechanism In Rowers Of Sub-altitude Inhabitants

Purpose: to observe the changes of physiological indexes and performance during altitude training and sub-altitude training, and systematic investigations were carried to insight into the mechanism of altitude and sub-altitude training and explore the characteristic and its regulating manner of these trainings.Methods: 16 rowers who long-term living in sub-altitude participated in the study. The subjects were separated into two groups randomly: altitude group (N=8, male 4 and female 4) and sub-altitude group(N=8, male 4 and female 4). Altitude group trained at altitude of 2260m and sub-altitude group at sub-sltitude of 1250m for 25 days, then both groups went to plain to train for 24 days. During the period, blood indexes (Hb, RBC, Hct, Ret, EPO, TTes, Cort, GH and IGF-1,etc) were monitered once a week and other indexes (weight, SaO2, skeletal muscle oxygenation in early morning, body composition and urine test, etc) were tested once two days. Before the experiment, after the period of altitude and sub-altitude training, and after the period of plain training the muscle cross-sectional area of quadriceps femoris and biceps femoris were measured with magnetic resonance imaging. The aerobic capacity, anerobic capacity and strength were tested during the period.Results and conclusions:1) After the altitude training, the capacity of blood transporting oxygen and skeletal muscle consuming oxygen elevated in altitude group, so the aerobic and anerobic performance increased. But the maximum strength did not increase because the exercise intension decrease and the skeletal muscle detraining.2) Sub-altitude training didn't increase the blood transporting capacity. But, the capacity of skeletal muscle consuming oxygen increased obviously because the exercise intension was maintained. So, the capacity of aerobic and anerobic elevated obviously. Another, the rowers'muscle cross-sectional area of quadriceps femoris didn't decrease, so the maximum strength of the lower limb increased obviously.3) Compared with altitude training, the increasing extent of performance in sub-altitude training group was larger than altitude group. It is obvious that the performance can increase through larger intension exercise in sub-altitude.4) The 7th day and the 21th day in plain were the best effector phase both altitude group and sub-altitude group.5) The subjects of this study lived at the sub-altitude for a long term. After they went to altitude, their altitude reactions were lighter, and the adaptation period was shorter. So, sub-altitude training can serve as the transition period before altitude training.