ALTITUDE TRAINING FOR IMPROVING SWIMMING PERFORMANCE AT SEA LEVEL. MITSUMASA MIYASHITA, YOSHITERU MUTOH and YOSHIHARU YAMAMOTO.

Transcription

1 ALTITUDE TRAINING FOR IMPROVING SWIMMING PERFORMANCE AT SEA LEVEL MITSUMASA MIYASHITA, YOSHITERU MUTOH and YOSHIHARU YAMAMOTO Abstract The present study was designed to investigate the effects of low altitude training on swimming performance with setting the same duration (3-wk) and the same level of altitude (2,300m). Eight male (Gml) swimmers aged 13 to 19 years and four male (Gm2) and eight female (Gf2) swimmers aged 13 to 18 years sent to Mexico City, and they conducted swimming work outs. All of them were top Japanese swimmers of various events. They repeated the swimming training twice a day continuously for four days with one day rest. Hemoglobin concentration (Hb), red blood cell count (RBC) and hematocrit (Hct) were determined before, during and after the altitude training several times. The values of Hb, RBC and Hct of all three groups increased significantly from before training to after training except Hb in Gm1. On the other hand, these three variables did not necessarily increase during the altitude training. Gm1 and Gf2 tended to increase Hb and RBC during the training. As for swimming performance at sea level, the individual best swimming records were improved significantly in 200m events, but not in 100m events in Gm1. Therefore, it may be concluded that 3-wk altitude (2,300m) training possibly improve swimming performance in the events equal to or longer than 200m at sea level. (Jpn. J. Phys. Fitness Sports Med. 1988, 37: 111 `116) key words: altitude training, Hb, RBC, Hct, Swimming performance I. Introduction Kellogg (6) has summarized the previous literatures concerning altitude physiology, and Grover (3, 4) reviewed the studies of adaptation to high altitude mainly from the view point of oxygen transport system. Interest in athletic performance at altitude came about when it was decided that the 1968 Olympic Games should be held in Mexico City (2,300m). Many exercise physiologists investigated the relationship between altitude and athletic performance. At that time, the main questions of interest were ghow long does it take to acclimate to the altitude? h. In summarizing these investigations, Astrand and Rodahl (1) stated that in order to attain optimal performance at altitude of 2,000m or higher in activities requiring the engagement of the maximal aerobic power, an acclimatization period of no less than three weeks was necessary. Although the opinions differ concerning the question whether or not the performance capacity at sea level is improved following exposure to high altitude (1), for instance, Grover (4) described that there seems to be no advantage to training at high altitude for sea level contests, there has been less studies on the effects on relatively low altitude training on athletic performance. Therefore, the purpose of this study was to investigate the effects of low altitude training on swimming performance at sea level by setting three weeks of duration and 2,300m of the level of altitude in order to satisfy the Astrand and Rodahl's condition (1). Laboratory for Exercise Physiology and Biomechanics, Faculty of Education, University of Tokyo Hongo, Bunkyo-ku, Tokyo, Japan (113)

2 112 MIYASHITA, MUTOH, YAMAMOTO II. Methods The subjects were eight male (Gm1) swimmers aged 13 to 19 years, four male (Gm2) and eight female (Gf2) swimmers aged 13 to 18 years. All of these athletes were Japanese top swimmers who were ordinarily living at sea level. For comparison, ten male (Gm3) and six female (Gf3) swimmers aged 14 to 22 years who were ordinarily living in Mexico City were observed. All subjects were informed of the purpose of taking blood samples and gave written consent before agreeing to participate. Gm1 went to Mexico City in December of 1982 for three weeks training and participated in the International Swim Meet held in Indianapolis (near sea level: 225m) three days after the altitude training. At the end of training, they participated in a swim meet held in Mexico City. Gm2 and Gf2 went to Mexico City in June of 1983 for the training of three weeks and participated in the Pre-Olympic Games held in Los Angeles (sea level) three days after the training. Mexican swimmers (Gm3 and Gf3) who conducted the swimming training usually in Mexico City came to Tokyo (sea level) and participated in the International Swim Meet in August of on Gm1, Gm2 and Gf2 one day before (testb), during (for Gm1 swimmers, tests and test2 were conducted on the 11 th and the 20 th day at Mexico City, respectively; for Gm2 and Gf 2, test 1, test2, and test3 were conducted the 8 th, the 14 th, and the 20 th day at Mexico City, respectively) and seven days after (testa) the altitude training several times (Fig. 1). These three variables were also determined on Gm3 and Gf3 in Mexico City and in Tokyo. Every blood sampling was performed early in the morning before breakfast. The analyses were conducted in two different laboratories; Tokyo Clinical Lab. and Mexico Clinical Lab., using Coulter Model-S blood counter. In the present study, therefore, the effects of training on hematological measurements were mainly compared in the two different ways; between testb before and testa after the altitude on Red blood cell count (RBC), hemoglobin concentration (Hb) and hematocrit (Hct) were determined training measured in Tokyo, and between test 1, test2 and test3 during the training in Mexico City (Fig. 1). During the three weeks training in Mexico City, the Japanese swimmers conducted swimming training (about twice a day for four successive 5,000m per two hours) days and spent a nontraining resting day. The amount of swimming distance was in the usual way tapered toward the Swim Meets. The composition of the Mexican swimmers' training was Fig. 1. Experimental design. Perpendicular arrows indicate blood samplings.

3 Altitude Training for Improving Swimming Performance at Sea Level 113 unknown. The significant values were determined differences between the mean III. by a paired t-test. Results The values of RBC, Hb and Hct of all three groups (Gm1, Gm2 and Gf2) increased significantly from testb to test, except Hb in Gm1 (Table 1 and 2). On the other hand, these three variables did not necessarily increase during the altitude training. Gm1 and Gf2 tended to increase RBC and Hb during the training. Mexican swimmers (Gm3 and Gf3) kept the almost same values of RBC, Hb and Hct even at seven days after arriving in Tokyo (Table 3). These values were 7.0 to 13.1% higher than the values of testb obtained for the Japanese swimmers in Tokyo. As for swimming performance, the individual performance (previous best) were significantly improved in 200m events, but not in 100m events in Gm1. On the other hand, great interindividual differences were found in the effects of altitude training on swimming performance, i. e. percent change from the individual's previous best ranged from -2.9 to +3.6%. Table 1. Mean values of RBC, Hb and Hct of eight male Japanese swimmers (Gml). *represent p<0.05 between testb and testa and represent p<0.05 between test1 and test2. Table 2. Mean values of RBC, Hb and Hct of four male (Gm2) and eight female (Gf2) Japanese swimmers. *, ** and *** represent p<(0.05, p<0.01 and p< between testb and testa. represent p<0.05 between test1 and test2 or test3.

4 114 MIYASHITA, MUTOH, YAMAMOTO Table 3. Mean values of RBC, Hb and Hct of ten male (Gm3) and six female (Gf3) Mexican swimmers. However, Japanese records were broken 17 times by five swimmers at relatively longer events in Gm2 and Gf2. The grestest improvement in male swimmers was +3.6% at 1,500m Fr from 16'38"00 to 16'01"86. That in female was +2.1% at 200m Br from 2'33'18 to 2'29"91 which was the best record of the world of Most of swimmers who could not improve performance made their physical conditions worse because of common cold, diarrhea etc. during the altitude training. At the Tokyo Swim Meet, all Mexican swimmers improved their records from their times at the preliminary the present swimmers in altitude. Strictly speaking, however, it is very difficult for swimmers to perform the same work outs both in altitude and at sea level. Therefore, the comparisons were made within the same groups in the present study. In the present study, the values of Hb, RBC and Hct of Japanese swimmers increased significantly from before altitude training to after altitude training except Hb in Gm,. Holmer (5) demonstrated the relative importance of anaerobic and aerobic metabolic reactions for the total energy yield with respect to maximal work time in swimming. From his figure, in 100m events taking less than one minute the anaerobic processes accounted for about 80% of the total energy yield, while in 200m events taking two minutes were responsible or more aerobic processes for 40 to 50% of the energy yield. Therefore, if oxygen transport system is improved by increased Hb during the low altitude training, the swimming times in 200m events would be expected to improve more than 100m events. On the other hand, if the swimmers tried to swim at high altitude, swimming performance in 200m events tended to be worse than that in 100m events. The present results obtained for Gml who partic- Meet in Mexico City. The records of the 200 m events were significantly (+2.0 }1.5%) improved. The greatest improvement was +3.9% at 1,500m Fr in male and +3.8% at 400m individual medley in female. IV. Discussion This study was designed to investigate the question of whether or not high altitude training was able to improve swimming performance at sea level. In this kind of study, the control group must be set which conducted the similar training at sea level as was done by Fig. 2. Percent changes in mean speed of Gm 1 in the swim meet at sea level after the altitude training and in the swim meet at altitude.

5 Altitude Training for Improving Swimming Performance at Sea Level 115 Fig. 3. The change in 50m swimming time at altitude and sea level from the previous best performance of 200m back stroke (male subject aged 18 yrs.). ipated in the Swim Meet at 2,300m and at sea level clearly proved these expectations (Fig. 2). When the swimming time of each 50m of 200m event of back stroke was compared between the trial at altitude and that at sea level, the effect of more efficient oxygen transport system acquired during the altitude training and that of reduced oxygen pressure at 2,300m on swimming performance were clearly observed (Fig. 3). The difference in time of each 50m swimming between the trial after the altitude training and that at high altitude definitely increased with distance. These results may be supported by the fact that significant improvement in swimming performance of 200m events was observed in the Mexican swimmers at the Tokyo Swim Meet. Five swimmers in Gm2 and Gf2 could not improve their best records after the altitude training, because of their worse physical conditions (common cold, sore throat, low back pain etc.). Therefore, if the physical conditions could be well maintained, they might have possibly improved their records of the events equal to or longer than 200m. V. Conclusion Based on the extent of the present trials of altitude training, it may be concluded that three weeks training at 2,300m can improve swimming performance at the events equal to or longer that 200m at sea level, if the physical conditions are well maintained. Acknowledgement The authors would like to say many thanks to Japan Scientific Instrument Co. LTD. for his great helps to blood analyses. (Received, Mar ) References 1) Astrand, P. O, and K. Rodahl (1970): Textbook of work physiology. New York. McGraw Hill Book Company. 2) Balke, B. (1960): Variation in altitude and its effects on exercise performance. In H. B. Falls (Ed.), Exercise Physiology. New York. Academic Press. 3) Grover, R. F.(1978): Adaptation to high altitude. In L. J. Folinsbee et al. (Eds.), Environmental stress. New York. Academic Press.

6 116 MIYASHITA, MUTOH, YAMAMOTO 4) Grover, R. F.(1979): Performance at altitude. In R. H. Strauss (Ed.), Sports medicine and physiology. Philadelphia. W. B. Saunders Company. 5) Holmer, I.(1980): Physiology of swimming man. In R. S. Hulton and D. I. Miller (Eds.), Exercise and sports science reviews Vol.7. Philadelphia. The Franklin Institute Press. 6) Kellogg, R. H.(1978): Some high points in high altitude physiology. In L. J. Folinsbee et al. (Eds.), Environmental stress. New York. Academic Press.