著者

濵野 純 田中 綾乃 田畑 泉

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.71, no.4, pp.319-331, 2022-08-01 (Released:2022-07-12)

参考文献数

49

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The purpose of this study was to examine the risk factors of stress fractures in terms of training distance and intensity in young male Japanese high school long-distance runners. Nine hundred and twenty-five runners from high schools, colleges, and work teams responded to our questionnaire. Our analysis of the questionnaire found that the onset rates of stress fractures in males were 25.0%, 40.2%, and 55.3% in high school runners, collegiate runners, and work team runners, respectively, suggesting that young Japanese long-distance runners are more likely to suffer from stress fractures than European and American runners. Stress fractures occurred in male high school and collegiate runners after training that had increased running distance (24.7% and 33.1%, respectively) or running intensity (17.0% and 9.6%), or both increased running distance and increased running intensity (29.8% and 34.6%), suggesting that an increase in running distance at moderate intensity might be a major risk factor in stress fractures in young male long-distance runners. Data from college and work team runners that ran all three years of high school show that stress fractures are most likely to occur in May of the high school freshman year. These results suggested a need to reconsider training programs for freshmen to prevent stress fractures in young runners.

著者

笹田 周作 石井 智也 小林 優里 清水 菜央 小宮山 伴与志

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.71, no.2, pp.239-247, 2022-04-01 (Released:2022-03-14)

参考文献数

30

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We investigated the effect of anodal transcranial direct current stimulation (anodal tDCS) on the performance of full-effort box stepping exercises in athletes and non-athletes. Twenty-one subjects (athletes: five men and six women, non-athletes: four men and six women) participated in this study. tDCS was applied through two electrodes placed on the vertex (anode) and the forehead (cathode). A 2-mA anodal stimulation was applied for 15 minutes, while sham stimulation was applied on different days with similar electrodes. Participants were asked to apply a maximal effort while stepping up and down a 10-cm tall box for 20 s following termination of the tDCS. The 20 s box stepping was repeated three times with 15 s of rest. The number of total steps was significantly increased following anodal tDCS compared to sham tDCS. The degree of increase in performance was more prominent in non-athletes than in athletes. In non-athletes, a differential pattern of fatigue in performance between stimulus conditions was observed. In contrast, this significant performance modulation between stimulus conditions was not detected in athletes. Our findings of improved stepping performance following anodal tDCS depended on the training level of the subject group; this implies modulation of descending command from CNS to active muscles by tDCS. It is suggested that the degree of neural modulation for controlling complex and full-effort leg movements due to tDCS is higher in non-athletes than in athletes.

著者

金久 博昭

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.65, no.1, pp.43, 2016 (Released:2016-01-24)

被引用文献数

2

著者

平井 雄介 田畑 泉

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.45, no.5, pp.495-502, 1996-10-01 (Released:2010-09-30)

参考文献数

23

被引用文献数

2 6

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This study examined the effects of (1) an intermittent training using a mechanically braked cycle ergometer and (2) resistance training using free weight on the maximal oxygen deficit and VO2max. For the first 6 weeks, six subjects trained using an intermittent training protocol five days per week. The exhaustive intermittent training consisted of seven to eight sets of 20 s exercise at anintensity of about 170% of VO2max with a 10 s rest between each bout. After the training, the maximal oxygen deficit increased significantly from 64.3±5.0 ml⋅kg-1 to 75.1±5.7 ml⋅kg-1 (p<0.01), while VO2max increased from 52.0±2.7 ml⋅kg-1⋅min-1 to 57.6±2.9 ml⋅kg-1⋅min-1 (p<0.05) . For the following 6 weeks, the subjects used the same intermittent training for 3 days per week and a resistance training for the other 3 days per week. The resistance training consisted of (1) 4 sets of 12 bouts of squat and leg curl exercise at 12 repetition maximum (RM) . (2) 2 sets of maximal bouts of the same exercise with a load of 90%, 80%, and 70% of 1 RM. After the training period, the maximal oxygen deficit increased further to the value of 86.8±5.9 ml⋅kg-1which was significantly higher than the value attained at the end of the intermittent training. On the other hand, VO2max did not increase significantly from the value observed at the end of the 6 weeks of intermittent training. Body weight was not significantly changed throughout the 12-week training period. Maximal circumference of the thigh did not changed during the first 6-week of the intermittent training period (pre-training: 57.1±1.2 cm, after 6-week training: 57.3±1.1 cm), while it increased significantly after the last 6-week combined training (59.0±0.8 cm, p<0.05) . In conclusion, this study showed that (1) high intensity intermittent training improves both the anaerobic and aerobic energy supplying systems, (2) additional resistance training with the intermittent training further increases the anaerobic energy supplying system, probably through increased muscle mass.

著者

武田 誠司 石井 泰光 山本 正嘉 図子 浩二

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.59, no.1, pp.107-118, 2010 (Released:2010-04-16)

参考文献数

28

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Running economy is an important factor in determining a performance of a long distance running. The purpose of this study was to examine the relationship between the running economy and the submaximal hopping economy. Twelve long-distance runners performed a submaximal repeated hopping exercise on a force platform at a frequency of 2.2Hz and the maximum five-repeated rebound jumping (5RJ). Jumping height, contact time, maximum ground reaction force and oxygen intake were recorded during submaximal repeated hopping exercise. In addition, they performed the submaximal running for a distance of 3200m on an outdoor 400m track. Oxygen intake was recorded during the submaximal running. Then running economy (RE = V/VO2) was calculated by using oxygen intake (VO2) and running speeds (V). Hopping economy (HE = h/VO2) was calculated by using oxygen intake (VO2) and average jumping height (h). As a result of this study, we confirmed that a submaximal repeated hopping exercise performed for a ten-minute period was an aerobic exercise and a steady-state exercise. There was a significant positive correlation between RE and HE (r = 0.805, p<0.01). These results suggest that hopping economy is an important factor in running economy. On the other hand, we did not find a significant correlation between HE and 5RJ. Furthermore, between RE and RJ index of the submaximal hopping exercise, a significant positive correlation was found (r = 0.735, p<0.01). Therefore, RE seems to be connected with the Stretch-shortening cycle (SSC) function of the legs. We conclude that the SSC ability of a long distance runner can be evaluated appropriately by using the submaximal repeated hopping exercise of this study.

著者

塩瀬 圭佑

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.66, no.2, pp.125-131, 2017-04-01 (Released:2017-03-19)

参考文献数

60

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Carbohydrate is a crucial energy fuel for exercise, and carbohydrate supplementation as peri-exercise has beneficial effects on exercise performance. However, recent studies have indicated the possibility that periodized carbohydrate restriction improves exercise performance. Carbohydrate restriction before exercise increases fatty-acid oxidation (FAO) and alternatively prevents carbohydrate consumption during exercise. This may contribute to the prevention of muscle glycogen depletion during endurance exercise competition. Additionally, acute and chronic studies have shown that peri-exercise carbohydrate restriction enhances molecular and functional adaptation related to FAO. Similarly, exercise training in a low-muscle glycogen state accompanied by carbohydrate restriction was reported to enhance mitochondrial biogenesis and improve FAO capacity, aerobic capacity, and endurance performance in untrained and highly trained subjects. The potential mechanism of these metabolic adaptations may be related to elevated circulating fatty-acid and adrenaline concentration during exercise with carbohydrate restriction and/or a low-muscle glycogen state. In addition, a decrease in muscle glycogen content may trigger signaling pathways related to FAO and mitochondria biogenesis by activating proteins with a glycogen-binding domain. This article reviews the effects of exercise with carbohydrate restriction and/or low-muscle glycogen state on metabolic adaptation and exercise performance and describes the molecular mechanisms and availability.

著者

今泉 和彦 立屋敷 かおる

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.54, no.3, pp.279-286, 2005 (Released:2006-12-01)

参考文献数

32

被引用文献数

2 1

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The present article briefly overviews the principal pathway of ethanol metabolism in the liver cell and hormonal regulations of ethanol metabolism, and a relationship between alcohol drinking volume (=alcohol consumption) and the degree of alcohol intoxication. This article also focuses on a possible mechanism of sex difference in rat liver cytosolic alcohol dehydrogenase (ADH) activity, and the effects of bile, bile acids, vegetable oils and unsaturated fatty acids on plasma ethanol levels and gastric emptying in ethanol-administered rats. Finally, the recent findings concernig a relationship between alcohol drinking and human health are described.

著者

鈴木 大地 中村 雅俊 大箭 周平 青木 孝史 江玉 睦明

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.68, no.2, pp.117-123, 2019-04-01 (Released:2019-03-16)

参考文献数

22

被引用文献数

1 2

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It is well known that eccentric exercise induces muscle damage that is characterized by a prolonged decrease in muscle strength and range of motion, development of delayed onset muscle soreness, and swelling. Therefore, the present study aimed to compare the acute effects of hold-relax stretching (HRS) with those of static stretching (SS) on muscle strength and soreness. The participants comprised 28 male volunteers randomly assigned to either the HRS group (N = 14) or the SS group (N = 14). Initially, the participants of both groups performed 60 maximal eccentric contractions of the knee extensors. Two and four days after this exercise, each group performed either HRS or SS for 60 s at a time and repeated them six times for a total of 360 s. Muscle strength and soreness during stretching and contraction were measured before and immediately after HRS and SS. The results showed that the muscle soreness observed after eccentric contraction significantly decreased immediately after both HRS and SS were performed two and four days later. In addition, there were no significant changes in muscle strength immediately after both HRS and SS were performed two and four days later. The rate of change in muscle soreness after HRS was significantly higher than that after SS two days post eccentric contractions. These results suggest that while both HRS and SS can effectively decrease muscle soreness, the effect of HRS on muscle soreness was larger than the effect of SS.

著者

河端 将司 加賀谷 善教 島 典広 西薗 秀嗣

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.57, no.2, pp.225-234, 2008-04-01 (Released:2008-08-13)

参考文献数

38

被引用文献数

6 4

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This study examined changes in intra-abdominal pressure and trunk activation during drop jump and the influence of those factors on performance. Intra-abdominal pressure (IAP) and surface electromyography (EMG) activity from the rectus abdominis (RA), transversus abdominis-internal oblique (TrA-IO) and erector spinae (ES) muscles were measured in seven males (22.3±1.0 years) during double-leg drop jumps from a 0.4 m height. Development of IAP (ΔIAP) and normalized rmsEMGs were calculated in the pre-contact, impact and push-off phases, after divided by ground reaction force data. TrA-IO activation which occurred prior to ground contact were the earliest and strongest compared to other muscles activation during each phase.ΔIAP during the impact phase coincided with the peak vertical force. There were significant positive correlations between ΔIAP, TrA-IO activation and vertical force per weight. In addition, the contact time correlated negatively with ΔIAP, TrA-IO activation and vertical force per weight. These findings indicate that ΔIAP and TrA-IO activation may contribute to trunk stability and efficient landing during double-leg drop jump.

著者

井上 和生 伏木 亨

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.55, no.2, pp.279-286, 2006-04-01 (Released:2007-05-10)

参考文献数

16

著者

中條 雅彦 牛 凱軍 門間 陽樹 小林 順敏 関 磊 佐藤 美加 郭 輝 大友 篤 崔 宇飛 只浦 寛子 斎藤 辰典 永富 良一

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.63, no.4, pp.383-389, 2014-08-01 (Released:2014-07-26)

参考文献数

40

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Coffee administration has been shown to increase maximum voluntary contraction and muscular endurance. However, no study has addressed the association between daily consumption of coffee with muscular function. This cross sectional study aimed to investigate the association between frequency of coffee consumption (CC) in daily life and muscle strength among a population of working adult men. This cross sectional study included men (n = 516, mean age: 47.1) who participated in an annual health examination conducted in Sendai. The monthly frequency of coffee consumed was reported by a brief-type self-administered dietary history questionnaire. Leg extension power (LEP) was measured as an index of muscle strength. Subjects were divided into tertile levels according to CC. Analysis of covariance was used to examine the relation between the tertile levels of CC and LEP. After adjustment for potential confounders (including all lifestyle factors), the adjusted means (95% confidence interval) of LEP across the tertiles of CC were 17.4 (16.6 - 18.1) for the lowest tertile, 17.9 (17.4 - 18.5) for the mid tertile, and 18.9 (18.3 - 19.5) for the highest tertile (p for trend = 0.007). Higher frequency of monthly coffee consumption was associated with higher muscle strength.

著者

管原 正志

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.64, no.1, pp.1-2, 2015 (Released:2015-01-25)

被引用文献数

1

著者

永澤 健 根本 勇 中村 夏実 岩竹 淳 黒田 善雄

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.50, no.1, pp.89-96, 2001-02-01 (Released:2010-09-30)

参考文献数

19

被引用文献数

2 2

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本研究は, クレアチン (Cr) ローディングがローイングパフォーマンスに及ぼす影響について検討することを目的とした.被検者は, 20名の国内トップレベルの男子学生ボート競技選手とし, ローイングエルゴメータにより, 実際の競技会をシミュレートした2000mローイングおよび最大努力の20秒ローイングを摂取前後に実施した.被検者を無作為にクレアチン (CRE) 群10名とプラセボ (PLA) 群10名に分け, 二重盲検法により1日20g (59×4/日) のCrあるいはプラセボを6日間摂取させた.その結果, 2000mローイングのタイムはCRE群において407.9±5.3秒から404.7±5.4秒へと有意な向上 (p<0.01) を示し, 一方, PLA群に有意な変化を認めなかった.最大努力の20秒ローイング時の発揮パワーは, Cr摂取によりに有意な変化を示さなかった.以上のことから, 高度にトレーニングされた男子ボート競技選手において, Crローディングは, 最大努力の20秒ローイングに効果がないものの, 2000mローイングのパフォーマンス向上に有効であることが示唆された.

著者

平井 雄介 田畑 泉

出版者

日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.45, no.5, pp.495-502, 1996-10-01

参考文献数

22

被引用文献数

1 6

---

This study examined the effects of (1) an intermittent training using a mechanically braked cycle ergometer and (2) resistance training using free weight on the maximal oxygen deficit and VO<SUB>2</SUB>max. For the first 6 weeks, six subjects trained using an intermittent training protocol five days per week. The exhaustive intermittent training consisted of seven to eight sets of 20 s exercise at anintensity of about 170% of VO<SUB>2</SUB>max with a 10 s rest between each bout. After the training, the maximal oxygen deficit increased significantly from 64.3&plusmn;5.0 ml&sdot;kg<SUP>-1</SUP> to 75.1&plusmn;5.7 ml&sdot;kg<SUP>-1</SUP> (p<0.01), while VO<SUB>2</SUB>max increased from 52.0&plusmn;2.7 ml&sdot;kg<SUP>-1</SUP>&sdot;min<SUP>-1</SUP> to 57.6&plusmn;2.9 ml&sdot;kg<SUP>-1</SUP>&sdot;min<SUP>-1</SUP> (p<0.05) . For the following 6 weeks, the subjects used the same intermittent training for 3 days per week and a resistance training for the other 3 days per week. The resistance training consisted of (1) 4 sets of 12 bouts of squat and leg curl exercise at 12 repetition maximum (RM) . (2) 2 sets of maximal bouts of the same exercise with a load of 90%, 80%, and 70% of 1 RM. After the training period, the maximal oxygen deficit increased further to the value of 86.8&plusmn;5.9 ml&sdot;kg<SUP>-1</SUP>which was significantly higher than the value attained at the end of the intermittent training. On the other hand, VO<SUB>2</SUB>max did not increase significantly from the value observed at the end of the 6 weeks of intermittent training. Body weight was not significantly changed throughout the 12-week training period. Maximal circumference of the thigh did not changed during the first 6-week of the intermittent training period (pre-training: 57.1&plusmn;1.2 cm, after 6-week training: 57.3&plusmn;1.1 cm), while it increased significantly after the last 6-week combined training (59.0&plusmn;0.8 cm, p<0.05) . In conclusion, this study showed that (1) high intensity intermittent training improves both the anaerobic and aerobic energy supplying systems, (2) additional resistance training with the intermittent training further increases the anaerobic energy supplying system, probably through increased muscle mass.

著者

紙上 敬太 西平 賀昭 東浦 拓郎

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.58, no.1, pp.63-72, 2009-02-01 (Released:2009-05-01)

参考文献数

26

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The interactive effects of exercise intensity and physical activity level on the brain and cognition of young adults were investigated using the electromyographic reaction time (EMG-RT), the P3, and the NoGo P3, as well as the contingent negative variation (CNV) of event-related brain potentials. Participants (n=26 : 24.0 ± 0.7 years) were divided on the basis of their regular physical activity level into active and inactive groups. Then, they performed a Go/NoGo reaction time task in the no exercise, control condition ; as well as after light, moderate, and hard cycling exercises. Results indicated that increases in P3 and NoGo P3 amplitude following moderate exercise were larger in the inactive group, suggesting that inactive individuals were more sensitive to exercise intensity than active individuals. Active individuals might be better able to sustain their attention during the Go/NoGo reaction time task, despite the exercise intensity. These findings are suggestive of a differential effect of exercise intensity on cognitive function that might be dependent on the level of regular physical activity. The effects of exercise intensity on EMG-RTs were observed across groups. However, the P3 latency was not affected by exercise intensity. These contradictory results are possible related to the nature of the cognitive task, such as its difficulty. Moreover, increases in CNV amplitudes following moderate exercise were larger than in other exercise conditions across groups, suggesting that motor preparation process is also facilitated by moderate, acute exercise. These findings provide additional evidence for the beneficial effects of acute aerobic exercise on the brain and cognition of young adults.

著者

木越 清信 尾縣 貢 田内 健二 大山 卞 圭悟 高松 薫

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.52, no.2, pp.167-178, 2003-04-01 (Released:2010-12-10)

参考文献数

16

被引用文献数

2 3

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本研究の目的は, 5秒間の全力ペダリング運動中における座位姿勢の変化が下肢筋群の筋活動および最大パワーに及ぼす影響を明らかにすることであった.被験者には, 大学陸上競技部に所属する男性10名 (21.5±1.9yrs, 178.8±4.7cm, 71.0±5.6kg) を用い, シートの高さを変化させた3種類 (High, MiddleおよびLow) の試技条件下で, それぞれ5秒間のペダリング運動を体重×0.1kpの負荷で行わせた.主な結果は以下の通りである.1.3回転の最大パワーは, HighがLowと比較して有意に高値を示した.2.骨盤傾斜角度は, HighおよびMiddleがLowと比較して有意に高値を示した.3.膝関節最大伸展角度および屈曲角度は, High, MiddleおよびLowの川頁に有意に高値を示した.4.脊柱起立筋および大腿二頭筋におけるmEMGは, HighがLowと比較して有意に高値を示した.5.Highにおいては, 3回転の最大パワーと大殿筋におけるmEMGとの間に有意な正の相関関係が認められた.また, 3回転の最大パワーと大腿二頭筋および外側広筋におけるmEMGとの間に正の相関傾向が認められた.以上の結果から, 5秒間の全力ペダリング運動において, シート高の変化による座位姿勢変化は下肢筋群, 特に股関節伸展筋群の筋張力および最大パワーに影響を及ぼす可能性があることが示唆された.

著者

久木留 毅 相澤 勝治 岡田 藍 徳山 薫平 河野 一郎

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.56, no.4, pp.429-436, 2007-08-01 (Released:2007-09-14)

参考文献数

31

被引用文献数

3 3

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[Objective] This study examined the effects of resting metabolic rate (RMR), sleeping metabolic rate (SMR), and diet-induced thermogenesis (DIT) during acute weight loss in elite male wrestlers.[Methods] Subjects were elite male wrestlers (n=6), who were instructed to reduce the body weight in seven days. RMR, SMR, and DIT were measured by indirect calorimetry in normal training phase and after rapid weight loss. Body composition and energy intake were also measured.[Results] Energy intake significantly decreased in rapid weight loss phase (P<0.05). After the rapid weight reduction, percent reduction of body weight (-4.4%), fat mass (-17.5%), and total body water (-3.2%) significant compare with that of normal training phase (P<0.05). RMR(-15.2%), and SMR (-11.8%) significantly decreased during acute weight loss (P<0.05). DIT(-89.4%) tended to be decrease during acute weight loss.[Conclusion] The present study suggests that rapid weight loss in elite male wrestlers causes decreases in RMR and SMR.

著者

松本 孝朗

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.64, no.1, pp.5-6, 2015 (Released:2015-01-25)

被引用文献数

1 1

著者

高橋 正人

出版者

The Japanese Society of Physical Fitness and Sports Medicine

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.45, no.1, pp.237-243, 1996-02-01 (Released:2010-09-30)

参考文献数

23

被引用文献数

1 1

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Unfortunately, anabolic androgenic steroid (AAS) abuse is prevalent in Japan. Most steroid abusers are amateur bodybuilders, powerlifters, wrestlers, and “fitness enthusiasists.” The case presented is of a young amateur bodybuilder, who suffered gynecomastia, whose only significant risk factor was his nonmedical use of an AAS.A 27-yr-old male was admitted to our hospital in December 1992 with gynecomastia. He reported starting to use an AAS, oxymetolone (Anadrol®) 30 mg daily, at the age of 23 yrs in 1987. He had developed bilateral painful gynecomastia, impotence and decreased sex drive within 3 months of starting AAS use. He stopped using it, and was admitted to another clinic in 1991. He took testosterone propionate (Testinon®) 25 mg weekly, but, as he was anxious about the long-term use or this medication, he was adimitted to our clinic.On physical examination his gynecomastia had diminished slightly, but he still had breast tenderness. All his laboratory examination results were almost within the normal ranges. Neverthless his serum free testosterone level was slightly low, so he took tamoxifen (Nolvadex®) and Chinese medicines. Consequently, his gynecomastia improved after treatment, for 5 months.Gynecomastia develops when an AAS is converted to estrogen. In conclusion, tamoxifen administration may be useful to reverse gynecomastia caused by AAS doping in sportsmen.

著者

森 奈津子 池添 冬芽 市橋 則明

出版者

一般社団法人日本体力医学会

雑誌

体力科学 (ISSN:0039906X)

巻号頁・発行日

vol.60, no.3, pp.319-326, 2011 (Released:2011-07-12)

参考文献数

28

被引用文献数

2 2

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This study investigated the changes in muscle thickness of transversus abdominis (TrA) during trunk muscle training. The subjects comprised 30 young men (average age 20.1 SD1.6 years) without low back pain. The muscle thickness of the upper region of TrA, middle region of TrA and lower region of TrA were measured by B-mode ultrasound. Muscle thickness were measured at rest and during the following 5 exercises; abdominal drawing, curl up, trunk ipsilateral rotation, trunk contralateral rotation and both straight leg raise in supine. There were no significant differences in the muscle thickness of the upper region of TrA between resting condition and all exercises. Muscle thickness during drawing, curl up and ipsilateral rotation were significantly greater than that at rest in middle region of TrA, and the rate of change in muscle thickness was the largest for drawing. Muscle thickness during drawing, curl up and ipsilateral rotation were significantly greater than that at rest in the lower region of TrA, and the rate of change in muscle thickness was the largest for ipsilateral rotation. These results suggested that the changes in muscle thickness of TrA during trunk muscle training showed different patterns depending on the region of TrA.