Physically trained and untrained preadolescent boys were examined experimentally for the effect of physical training on thermoregulatory responses to heat and cold. In summer they were asked to wear swimming pants and dip their legs up to the knees into water at 42.3°C for 60 minutes under given environmental conditions (30°C DB and 70% RH) . Then they were exposed to a given cold environment (18°C DB and 60% RH) in a resting posture for 60 minutes. Rectal and mean skin temperatures, total body sweat rate, puls rate, metabolism, etc, were measured. The pulse rate at rest was lower in those trained physically than in those untrained. The rectal temperature increased and decreased less remarkably during exposure to heat and cold, and the total body sweat rate to the increment of rectal temperature tended to be higher in those trained than in those untrained. The other variables measured during both cases of exposure failed to respond to physical training. These results suggested a possibility that physical training might be a means of improving the thermoregulation in preadolescents, although its effect might be inconsiderable.

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The present study was designed to examine the thermoregulatory response to the alternate stress of heat and cold in relation to physical training. A heat stress was given as a 60-minute foot bath in water at 43°C in the air condition of 30°C DB and 60% RH, and a cold stress as a 60-minute exposure to an atmosphere of 20°C DB and 60% RH in summer and 17°C DB and 60% RH in winter. Two experimental conditions of four-hour exposure were set up by combining the hourly heat and cold stress alternately : Condition I was initiated with the heat stress and ended with the cold one, and condition II vice versa. In these conditions, both heat and cold stresses were given twice. In summer, as well as in winter, physical untrained and trained adult males in swimming pants were exposed to alternate heat and cold stress extending for four hours. Rectal and mean skin temperatures were taken every 5 minutes. A ten-minute metabolic rate was measured every 20 minutes during the exposure period. The effect of physical training was generally more remarkable in condition I than in condition II, and in summer than in winter. In condition I, the trained group had a smaller variation in rectal temperature and a smaller rate of variation from a resting value in energy consumption throughout the four-hour exposure than the untrained. The differences between the mean skin temperature in the last stage of the first exposure and that of the second tended to be smaller in the trained group than in the untrained. Reduced differences between these values were noticed in the untrained men after physical training. These results indicate that the effect of physical training was discernible on the thermal adaptability to the alternate stress of heat and cold. It was concluded that physical training generally promoted the acclimatization and enhanced tolerance capacity to heat and cold.

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Changes in serum enzyme activities (GOT, GPT and ChE) were investigated in trained and control subjects both of which were made to perform exercises of three different intensities (mild, moderate and heavy) . It was thought that this study might aid in elucidating the relationship between serum enzyme activities and the blood lactic acid level as an index of hypoxia.
The results are summarized as follows:
1) Both activity levels of the serum enzymes and the concentration of blood lactic acid were higher at rest in the control subjects than in the long distance runners.
2) Activity levels of serum ChE as well as GOT, GPT increased in propotion to the intensity of work.
3) In serum GOT, GPT and ChE activities no statistically significant difference was found between the two groups in all work loads.
4) Relationships between the increase of blood lactic acid concentrations and those of the serum enzyme activities at three minutes after the exercise were all found statistically significant (P<0.001) (with GOT r=0.845, GPT r=0.768 and ChE r= 0.835) .

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異なる4種類の強度で自転車エルゴメーター作業を行わせた際の大腿血流量と大腿容積変化を測定した。
作業終了直後の大腿血流量は, ある作業強度 (120Watt) までは強度の増大に伴って増大した。
作業終了直前の大腿容積の増加量は, 作業強度の増大に伴って増大した。
作業終了直後の大腿血流量と作業終了直前の大腿容積の増加量との間には, 密接な関係が認められた (r=0.76, P<0.001) 。

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水泳時の呼吸に関する研究の一環として, 体位, immersion及び水泳トレーニングの肺換気力学特性に及ぼす影響を分析するため, 大学水泳選手ならびに体育専攻学生 (対照群) それぞれ7名を被検者として, 最人呼気及び最大吸気flowvolume, 肺活量 (VC) , 呼気予備量 (ERV) , 残気量 (RV) を測定した。測定条件は陸上及び水中であり, 体位は立位, 背位, 腹位の三体位とした。
立位ではimmersionの影響を顕著に受け, 全肺気量は水中で有意な減少を示した。これはVCとRVが共に減少したことによる。また, 立位のERVは水中で顕著な減少を示したが, 予備吸気量はわずかに増大した。しかし, 背位と腹位の肺気量は, 背位でERVに増大を認めたことを除けば, immersionにより有意に変化しなかった。立位でimmersionの影響が著しいのは, 胸廓や腹部を圧迫する水圧の効果が背位や腹位に比べて大きいことによると解釈された。水泳選手の各肺気量分画は対照群に比べ大である傾向を示したが, 両群に対する水圧の影響は類似していた。
最大呼気流量 (Vp) は吸気時には呼気時より著しく小さい。また, Vpは吸気時, 呼気時共に水中では減少するが, 特に吸気時のVpは水中での減少が大きい。さらにVpは立位に比べ腹位や背位では減少するが, 体位変化のVpに対する影響は吸気時に特に顕著である。これに対して, V₅₀, V₂₅及びVVは吸気時には呼気時より著しく大となる。さらにこれらの指標は呼気時, 吸気時共に水中で減少した。
水泳選手と対照群の動的な肺換気力学特性の差は呼気時よりも吸気時に顕著に現われ, 水泳選手の吸気時のV_p, V₅₀, V₂₅, VVは対照群に比して有意に高い値を示した。水泳では特に吸気に大きなパワーを要求されるところから, これは水泳トレーニングの影響であろうと考えられた。

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加齢ラットにおけるtriglycerideの増加を, 心筋, 肝臓, 血清, 骨格筋 (人腿直筋, 前〓骨筋, 長指伸筋, 足底筋, ヒラメ筋) , 副睾丸脂肪組織について量的並びに質的に検討し, 相互関係を追究した。
1) 各組織のtriglyceride含有量の変動はおよそ14ケ月齢以後のラットに認められた。
2) 心筋, 前〓骨筋, 長指伸筋のtriglyceride含有量は1, 3.5, 14, 21ケ月齢ラットではほとんど変動が認められなかった。
3) 肝臓triglycerideは21ケ月齢ラットで著しく低下し, 統計学的有意差 (P<0.05) が認められた。
4) 大腿直筋, 足底筋, ヒラメ筋のtriglyceride含有量は14ケ月齢あたりから徐々に増加し, 21ケ月齢ラットでは統計学的に有意 (P<0.05) な増加となった。
5) 14ケ月齢並びに21ケ月齢ラットの各組織のtriglyceride構成脂肪酸分画を比較すると, 21ケ月齢ラットではC₁₈, C_18-1, C_18-2の増加が認められ, 血清中遊離脂肪酸分画への反映は認められなかった。また, triglyceride含有量の増加が認められた骨格筋 (大腿直筋, ヒラメ筋) でも同様の変化が認められた。
以上の結果から, 加齢ラットにおけるtriglycerideの変動はそれぞれの組織により異なり, triglycerideの増減が著しい組織ではその構成脂肪酸にも質的な差が生じることが示唆された。

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This paper was aimed to evaluate cardiovascular function and physical fitness of athletes during active athletic life and after the cessation of physical training, and to discuss on cardiovascular future of ex-athletes. Subjects included 301 men and 64 women athletes who participated in Tokyo Olympic games. Four to 12 years' follow-up study was performed in 88 men athletes. (1) . The characteristic findings of ECG during active athletic period were sinus bradycardia, increased voltage of QRS, irbbb and first or second degree AV block. Ninety-five percents of cases with sinus bradycardia and all cases with AV block showed normal heart rate and normal AV conduction within 4 years the cessation of training. Irbbb persisted longer than other items and 60 percents of cases with irbbb had the similar findings 12 years after the cessation of training. (2) . Increased heart size observed during active athletic life returned to normal in 4 to 8 years after the cessation of training. (3) . Blood pressure was not changed before and after the cessation of training. (4) . Little changes were observed in grip strength, 12 years after the cessation of training. Although there was a slight decrease on back lift strength and ability of vertical jump 12 years after the cessation of training, they were still higher than normal. (5) . Havard step test score was obviuously decreased 12 years after the cessation of training, although it was still maintained highly than normal. From this study, it may be inferred that the effect of physical training to cardiovascular function does not persisit for a long time. On the contrary, increased muscle strength such as grip strength, back lift strength and vertical jump persist for a rather long time, once it was increased by vigorous physical training.

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