著者

大島 秀武 志賀 利一 森谷 敏夫 桝田 出 林 達也 中尾 一和

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.3, pp.295-303, 2003-06-01 (Released:2010-09-30)

参考文献数

34

被引用文献数

1 2

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The purpose of the present study was to develop a new method that enables individualized determination of the optimal exercise intensity for health promotion. Our study was based on the following observations : (1) physical activity at ventilatory threshold (VT) has been useful for enhancing physical fitness and even improving medical conditions such as heart failure, hypertension and diabetes, (2) exercise intensity at VT is characterized by suppressed vagal activity, and (3) vagal activity can be evaluated by analyzing heart rate variability (HRV) . In the first study we defined a criteria for determining the exercise intensity corresponding to VT using HRV analysis (heart rate variability threshold, THRV) . In 16 normal subjects, a time series of ECG RR interval were recorded and the means of the sum of the squared differences in successive RR intervals (MSSDs) were calcu-lated during a ramp exercise test with a cycle ergometer. Based on the values of MSSD and the dif-ferences in successive MSSDs (ΔMSSD) at the intensity of VT, we defined the criteria of THRV as follows : MSSD<25 msec2and ΔMSSD<6 msec2. Another exercise test with a cycle ergo-meter was performed to evaluate the relationship between THRV and VT in 63 normal subjects. Heart rate (HR) and oxygen uptake (VO2/wt) at THRV were 111.8±13.2 beats/min and 15.2±4.4 ml/kg/min, and HR and VO2/wt at VT were 116.2±11.6beats/min and 16.5±3.7ml/kg/min, respectively. There was a significant correlation between THRV and VT (HR : r=0.82, p<0.001, VO2/wt : r=0.88, p< 0.001) . Thus, THRV and VT provided almost identical exercise intensities. As a result, we propose that, similar to VT, THRV can be used as an indicator of the optimal exercise intensity suitable for health promotion in normal subjects.

著者

田口 素子 高田 和子 大内 志織 樋口 満

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.4, pp.423-432, 2011 (Released:2011-08-30)

参考文献数

24

被引用文献数

6 4

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The aim of the present study was to examine the validation of prediction equation of basal metabolic rate (BMR) in Japanese female athletes. The study population consisted of 122 Japanese female athletes (age 20.2 ± 1.3 years, height 162.5 ± 6.3 cm, body weight (BW) 57.4 ± 7.7 kg, and fat-free mass (FFM) 45.5 ± 5.1 kg). Body composition was estimated by using air displacement plethysmography (BOD POD System). BMR was measured by indirect calorimetry using dougras bag tequnique, and predicted BMR was calculated from different equations based on FFM. When compared with measured BMR, predicted BMR from the equation of Taguchi et al. (BMR (kcal/day)= 26.9×FFM (kg)+ 36) and equation of Owen et al. were not significantly different. Whereas, predicted values from equation of Japan Institute of Sports Sciences, National Institute of Health and Nutrition and Cunningham were significantly different from measured value. Estimation error and Total error were smaller in equation of Taguchi et al. and Owen et al., however, equation of Owen et al. had a larger estimation error in the subjects who was small body size (less than 42kg) or large body size(more than 69kg). Furthermore, newer equation of Taguchi et al. (BMR=27.5×FFM+5) was developed from the pool data (n=205) in the present study. Standard error of estimation (SEE) of this equation was smaller than the equation of Taguchi et al., and systematic error was hardly observed.In conclusion, the newer equation of Taguchi et al. developed from measured BMR of Japanese female athletes was useful to predict BMR.

著者

駒澤 純 山田 茂

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.4, pp.367-384, 2006-08-01 (Released:2007-05-15)

参考文献数

120

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This review explores novel possibilities of skeletal muscle hypertrophy mechanism based on previous studies. Hypertrophy and/or regeneration of skeletal muscles are caused by activation of satellite cells, induced by mechanisms such as growth factors and cytokines. Many unsolved problems, however, yet remain concerning signaling pathways, activated by such substances, and regulation of transcriptional factors and cell cycles.In recent years, possible involvement of not only satellite cells but also tissue-specific stem cells in skeletal muscle hypertrophy has been reported from studies made on stem cell transplantation in muscle regeneration.It has been elucidated that differentiation plasticity of tissue-specific stem cells contributes to hypertrophy and/or regeneration of skeletal muscles. Moreover, satellite cells have come to be regarded as one kind of tissue-specific stem cells, since they have been known to exhibit diversity, by their differentiating into not only skeletal muscle cells but also other tissue cells, as well as self renewal capacity.This review also summarizes findings on signaling pathways based on ligand receptor characterization. Among the various signaling pathways, focus was especially placed on the possibilities of Wnt signaling pathway and Notch signaling pathway on skeletal muscle hypertrophy, indicating that Wnt expression in adult muscle stem cells leads to regulation of skeletal muscle hypertrophy.It has also become evident that Notch signaling pathway is associated with the activation of satellites cells, and that functional decline of such signaling pathway causes a decline in the activation of satellite cells. Such functional decline of Notch signaling pathway has also been revealed as the reason for the decline of regenerative capacity of skeletal muscles due to advancing age. Further discussion on the involvement of Notch signaling pathway in skeletal muscle hypertrophy is made based on these results. As indicated above, the roles of ligands and/or receptors of canonical growth factors, signaling pathways, and transcriptional factors contributing to skeletal muscle hypertrophy were reexamined in this review, after which the contribution of tissue-specific cells to skeletal muscle hypertrophy was discussed based on the results of muscle regeneration studies. Furthermore, focus was centered on Wnt and Notch signaling pathways, both of which are attracting renewed attention, and study was made on the possibility of the involvement of these pathways in skeletal muscle hypertrophy process.

著者

小林 寛道 八木 規夫

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.40, no.6, 1991-12-01

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1989年8月27日、札幌市で行われた北海道マラソンに出場した日本の代表的マラソンランナーH.T選手を対象として、マラソンレース中の体表面温度を赤外線映像装置(日本アビオニクス株式会社TVS)を用いて併走車上より撮影記録した。計測点は、顔(前額部)、胸(ランニングシャツのかからない胸元部位)、腹部(ランニングシャツの表面)、大腿(大腿中央部)の4点とした。

著者

真田 樹義 宮地 元彦 山元 健太 村上 晴香 谷本 道哉 大森 由実 河野 寛 丸藤 祐子 塙 智史 家光 素行 田畑 泉 樋口 満 奥村 重年

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.3, pp.291-302, 2010 (Released:2010-07-15)

参考文献数

23

被引用文献数

17 8

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The purpose of this study was to develop prediction models of sarcopenia in 1,894 Japanese men and women aged 18-85 years. Reference values for sarcopenia (skeletal muscle index, SMI; appendicular muscle mass/height2, kg/m2) in each sex were defined as values two standard deviations (2SD) below the gender-specific means of this study reference data for young adults aged 18-40 years. Reference values for predisposition to sarcopenia (PSa) in each gender were also defined as values one standard deviations (1SD) below. The subjects aged 41 years or older were randomly separated into 2 groups, a model development group and a validation group. Appendicular muscle mass was measured by DXA. The reference values of sarcopenia were 6.87 kg/m2 and 5.46 kg/m2, and those of PSa were 7.77 kg/m2 and 6.12 kg/m2. The subjects with sarcopenia and PSa aged 41 years or older were 1.7% and 28.8% in men and 2.7% and 20.7% in women. The whole body bone mineral density of PSa was significantly lower than in normal subjects. The handgrip strength of PSa was significantly lower than in normal subjects. Stepwise regression analysis indicated that the body mass index (BMI), waist circumference and age were independently associated with SMI in men; and BMI, handgrip strength and waist circumference were independently associated with SMI in women. The SMI prediction equations were applied to the validation group, and strong correlations were also observed between the DXA-measured and predicted SMI in men and women. This study proposed the reference values of sarcopenia in Japanese men and women. The prediction models of SMI using anthropometric measurement are valid for alternative DXA-measured SMI in Japanese adults.

著者

前田 有美 横山 典子 高橋 康輝 土居 達也 松元 圭太郎 上野 裕文 久野 譜也

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.2, pp.269-278, 2007-04-01 (Released:2007-05-25)

参考文献数

43

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The purpose of this study was to investigate the effects of combined resistance training and aerobic training with protein intake after resistance training on body composition in obese middle-aged women. The subjects were 42 middle-aged women (age : 56.5±4.3 years, BMI : 26.6±2.3 kg/m2), who were classified into three supplementation groups: Protein group (PG), Isocalorie placebo group (IG), and Noncalorie placebo group (CG) by Double Blind Randomized Trial. The training program consisted of combined resistance training and aerobic training for 10 weeks, 5 times per week: twice a week in a university training room and 3 times per week at home. The subjects took the nutrient supplement immediately after each resistance training session. We measured body weight (Bw), body fat volume (Bf) by bioelectrical impedance analysis (BIA), and cross-sectional area (CSA) of muscle of the thigh extensor group (Te), flexor group (Tf), and psoas major (Pm) by magnetic resonance imaging (MRI) before and after the 10-week training period. Irrespective of group, Bw and Bf showed a significant decrease after the training period compared to before (p<0.001), and the CSA of Te muscle showed a significant increase after the training period (p<0.01). Moreover, the interaction of time×group was accepted in the CSA of Pm muscle (p<0.05), and the increase in muscle volume for PG was the highest increase among the three supplementation groups (p<0.05)(PG : 2.1±0.8 cm2, IG : 1.3±1.0 cm2, CG : 1.3±0.9 cm2). These results suggest that combined training in middle-aged obese women improves body composition, and resistance training with protein intake may increase the CSA of muscle of psoas major.

著者

富家 孝 永田 晟

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.39, no.5, pp.293-297, 1990-10-01

被引用文献数

1

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Twenty biochemical components of serum were compared between normal healthy subjects and professionalwrestlers undergoing maximum traininng daily. Significant difference was found for 13 blood components:creatining, uric acid, calcium, inorganic phosphorus, LDH, GOT, GPT, γ-GTP, alkaline phosphatase, direct bilirubin, cholesterol, triglyceride and glucose. Exept for direct bilirubin, 12 parameters in wrestlers were higher than in healthy subjects. The higher consentrations of LDH, calcium, inorganic phosphorus, alkaline phosphatase and creatinene were considerd to be related to heavier physical exercise and special diet. The higher concentrations of alkaline phosphatase, calcium and inorganic phosphorus were thought to be mainly related to bone metabolism.

著者

征矢 英昭 菊池 章人

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.67, no.1, pp.9, 2018 (Released:2018-01-19)

参考文献数

3

著者

図子 浩二 高松 薫

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.44, no.1, pp.147-154, 1995-02-01

参考文献数

22

被引用文献数

4 9

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本研究では, 跳躍選手や球技選手が必要とするバリスティックな伸張―短縮サイクル運動の遂行能力を高めることに対して, 筋力および瞬発力を高めることが, どのような意味を持つのかについて, 健康な男子体育専攻学生99名を用いて検討した.<BR>バリスティックな伸張一短縮サイクル運動の遂行能力を評価するための指標として, RDJ<SUB>index</SUB>を測定した.また, 筋力を評価するための指標として, スクワット姿勢による最大脚伸展力 (Smax/BW) , 瞬発力を評価する指標として, 垂直跳の跳躍高 (CMJh) をそれぞれ測定した.なお, RDJ<SUB>index</SUB>は, 台高0.3mからのリバウンドドロップジャンプにおける滞空時間 (RDJt<SUB>a</SUB>) から求めた跳躍高を踏切時間 (RDJt<SUB>c</SUB>) で除したものであり, できるだけ短い踏切時間によって高い跳躍高を獲得するための能力を評価するものである.<BR>本研究の結果は次の通りである.<BR>(1) RDJ<SUB>index</SUB>, Smax/BW, CMJhの相互間には, いずれも有意な相関関係が認められたが, 相関係数はあまり高い値ではなかった.このことは, 三つの指標は, いずれも脚の筋力およびパワー発揮に関する特性を表すものであるが, 相互の類似性は必ずしも高くないことを示唆するものである.<BR>(2) RDJ<SUB>index</SUB>を構成する要因であるRDJt<SUB>c</SUB>とRDJt<SUB>a</SUB>との間には, 有意な相関関係は認められなかった.このことは, バリスティックな伸張一短縮サイクル運動の遂行能力が, 運動遂行時間の短縮能力と高い跳躍高の獲得能力の二つの独立した異なる能力によって決定されることを示唆するものである.<BR>(3) RDJt<SUB>a</SUB>とSmax/BW, RDJt<SUB>a</SUB>とCMJhとの間には, いずれも有意な相関関係が認められた.しかし, RDJt<SUB>c</SUB>とSmax/BW, RDJt<SUB>c</SUB>とCMJhとの間には, いずれも有意な相関関係は認められなかった.これらのことは, 筋力や瞬発力は, 高い跳躍高の獲得能力には関係するが, 運動遂行時間の短縮能力には必ずしも関係しないことを示唆するものである.<BR>(4) RDJ<SUB>index</SUB>が同じ値であっても, RDJt<SUB>c</SUB>とRDJt<SUB>a</SUB>には大きな個人差のあることが認められた.このことは, トレーニングの主なねらいが, 高い跳躍高の獲得能力にある者もいれば, 運動遂行時間の短縮能力にある者もいることを示唆するものである.<BR>本研究で明らかにしたバリスティックな伸張―短縮サイクル運動の遂行能力と, 筋力および瞬発力との関係は, 跳躍選手や球技選手などの筋力・パワートレーニング法に関する一つの有用な知見になるものと考えられる.

著者

千村 晃

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.63, no.1, pp.128, 2014 (Released:2014-01-24)

参考文献数

2

著者

市橋 則明 吉田 正樹

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.42, no.5, pp.461-464, 1993-10-01

被引用文献数

8 4

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A study was conducted to determine the minimum quantity of leg exercise required to prevent disuse atrophy of the quadriceps femoris muscle during bed rest. The subjects were 10 normal young university students with a mean age of 21.1 years. First, analysis of rectified filtered electromyography(RFEMG)was performed on the rectus femoris and vastus medialis during walking with cadences of 100 steps/min and 150 steps/min. Then, the effects of straight leg raising(SLR), patella setting(PS), knee extension-flexion in a supine position(KEF)and knee extension in a sitting position(KE)were analysed for each muscle using the same method. Based on the value of RFEMG for each muscle during walking, the repetition number for each exercise was calculated. For the rectus femoris, the repetition number for each exercise corresponding to 10000 steps with a cadence of 100 steps/min was 289 for SLR, 466 for PS, 1255 for LEF and 1663 for KE. For the vastus medialis, the corresponding numbers were 1223, 381, 6367 and 2170, respectively. When the cadence increased to 150 steps/min, the repetition number of each exercise for each muscle also increased. These results indicate that high-repetition exercise is recommendable to prevent disuse atrophy of the quadriceps femoris muscle. Therefore, the activity of patients should be increased to stimulate weakened muscles such as the quadriceps femoris during hospitalization.

著者

田代 浩一 西島 壮 征矢 英昭

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.53, no.6, 2004-12-01

著者

苅山 靖 林 陵平 吉田 拓矢 図子 あまね 図子 浩太佑 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.67, no.2, pp.187-197, 2018-04-01 (Released:2018-03-16)

参考文献数

44

被引用文献数

1

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Movement control and muscle function for pelvic movement in the frontal plane (pelvic elevation) are important for various single-leg sports activities. We aimed to clarify mechanical characteristics of pelvic squat (P-Sq: single-leg squat exercise with emphasis on pelvic elevation, developed by our research group) compared with the double-leg squat (D-Sq) and single-leg squat (S-Sq). Twelve male track and field athletes performed D-Sq, S-Sq, and P-Sq exercises at various loads (90%, 75%, and 60% of 1-repetition maximum [1RM]), using maximum effort. Kinematic and kinetic data were calculated using data recorded with a motion capture system and force platforms. We observed the highest values with P-Sq, followed by S-Sq and D-Sq under all load conditions as follows: peak vertical ground reaction force and rate of force development (RFD), range of pelvic elevation, peak pelvic elevation velocity, peak powers associated with hip abduction torque and trunk lateral flexion torque. In P-Sq, RFD at 90% 1RM was smaller than under the other load conditions, whereas peak vertical ground reaction force at 90% 1RM was larger than under the other load conditions. There were no differences among load conditions with regard to hip abduction and trunk lateral flexion torques and powers. Therefore, characteristics of P-Sq compared to those of D-Sq and S-Sq are 1) larger and faster pelvic elevation, using related muscles (hip abductors and trunk lateral flexors) under all load conditions, 2) larger peak ground reaction force with pelvic elevation under large load conditions, and larger RFD in pelvic elevation under low load conditions.

著者

久保 啓太郎 金久 博昭 福永 哲夫

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.50, no.6, 2001-12-01

著者

弘 卓三 石井 哲次 冨岡 徹 森田 恭光 山本 鉄雄

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.46, no.5, pp.445-451, 1997-10-01

参考文献数

28

被引用文献数

1

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We have developed a mouth guard which has revolutionized the shape and material of the conventional mouth piece. The H shape mouth guard has the unique shape like that of an H. Even with the new shape of the mouth piece it does not hinder the performance of the wearer. The following are the fundamental data collected by our group. In this study we examined its influences on leg power, the carry(the distance a golf ball is hit)and the motion of the club head during a tee off. The results are as follows : 1) By wearing or setting the mouth guard, the variation of leg power, measured with a Sybex II, showed an increase at selected angular verocity. The rate of increase averaged aproximately 15%. 2) The amount of work in anaerodush, an intensive, but short exercise, increased significantly by 1.25 seconds. 3) As for golf, all four of the test subjects joint performance increased their carries by 5.2 to 11.6 yards, using a 1 st wood. 4) Also the fluctuation of the head of the club decreased from 7.3 cm to 3.6 cm on average. Our group have found that the new H shaped mouth guard can absorb shock as well as not hinder the performance of the individual who is wearing it. Thus, the H shape mouth guard can be worn durinlg sports to enhance the participant's performance.

著者

半田 徹 加藤 浩人 長谷川 伸 岡田 純一 加藤 清忠

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.2, pp.159-168, 2005 (Released:2006-12-01)

参考文献数

22

被引用文献数

3 7

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To compare the effectiveness of five different muscle training movements on the biceps brachii, latissimus dorsi and trapezius muscles, eight weight-trained men (age, 20.4±0.5 years) were asked to perform three repetitions, at 70% one repetition maximum, of upright rowing (UR) and bent-over rowing (BR) exercises using a barbell ; and seated rowing (SR), front lat pull-down (LPf) and back lat pull-down (LPb) exercises using a Universal Machine. The activities of the biceps brachii, latissimus dorsi, and trapezius during the elbow flexsion and elbow extension phases of each exercise were analyzed using integrated electromyography (EMG) and normalized I-EMG. The results were as follows :1. The mean nrmsEMG values for the biceps brachii were larger during UR and LPf exercises than during BR, SR, and LPb exercises, suggesting that UR and LPf are more effective than the other movements for training the biceps brachii. The mean nrmsEMG values for the latissimus dorsi were larger during SR, LPf, and LPb exercises, followed by BR and UR exercises (in descending order), suggesting that SR, LPf, and LPb exercises are more effective than the other movements for training the latissimus dorsi.2. The mean nrmsEMG values for the upper trapezius were larger during UR and BR exercises than during SR, LPf, and LPb exercises, suggesting that UR and BR exercises are more effective than the other movements for training the upper trapezius. The mean nrmsEMG values for the middle trapezius were larger during BR and SR exercises than during UR, LPf, and LPb exercises, suggesting that BR and SR exercises are more effective than the other movements for training the middle trapezius. The mean nrmsEMG values for the lower trapezius were larger during BR exercise than during other movements, suggesting that BR exercise is more effective than the other movements for training the lower trapezius.3. In all the exercises, each muscle showed a higher nrmsEMG value during the elbow flexsion phase than during the elbow extension phase. This observation suggests that the training method examined in this study should emphasize the elbow flexsion movement.The present results suggest that UR exercise is the most effective movement for training the biceps brachii and upper trapezius, BR is most effective for training the upper trapezius, middle trapezius and lower trapezius, SR is most effective for training the latissimus dorsi and middle trapezius, LPf is most effective for training the biceps brachii and latissimus dorsi, and LPb is most effective for training the latissimus dorsi.

著者

小川 新吉 永井 信雄

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.17, no.4, pp.150-151, 1968-12-01

著者

永富 良一

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.51, no.1, 2002-02-01

著者

湯浅 景元 福永 哲夫

出版者

日本体力医学会

雑誌

体力科學 (ISSN:0039906X)

巻号頁・発行日

vol.36, no.1, pp.36-41, 1987-02-01

被引用文献数

4

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全身にわたる皮下脂肪厚を測定し、その分布パターンを明らかにした研究は今のところみられていない. 本研究では,2名の成人男子を対象にして,超音波診断装置(Bモードlinearタイプ)を用いてほぼ全身の皮下脂肪厚を測定し,その分布パターンを明らかにすることにした. 本研究によって得られた結果は次のようであった. 1) 体幹で皮下脂肪が厚い箇所は,臍を中心とした腹部中央と側腹から腰部外側にかけての部分であった. 2) 体幹で皮下脂肪が薄い箇所は,胸部上方の部分であった. 3) 体肢では大腿や上腕のように中枢に近いところにある体節で,かつ中枢に近づくほど皮下脂肪は厚かった. 4)以上のことから,体幹では皮下脂肪厚が幅広く分布しているのに対して,体肢ではほぼ均一に分布する傾向のみられることが示唆できた.

著者

相澤 勝治

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.5, pp.455-462, 2016-10-01 (Released:2016-10-03)

参考文献数

47

被引用文献数

2

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The plasticity of skeletal muscle facilitates adaptation to various stimuli. Sex steroid hormones (androgens and estrogens) are involved in a variety of physiological and pathological processes. In skeletal muscle, sex steroid hormones affect growth, strength, metabolism, and antioxidant levels and are associated with exercise-induced skeletal muscular adaptation. Sex steroid hormone levels also decrease with aging and are thought to be a factor in muscle atrophy. Though sex steroid hormones play an important role in skeletal muscular homeostasis, the role of the endocrine system in muscle plasticity is unknown. Sex steroid hormones are synthesized from cholesterol by steroidogenic enzymes, such as 3β-hydroxysteroid dehydrogenase (HSD), and 17β-HSD, with testosterone being irreversibly converted to estrogen by aromatase cytochrome P450 (P450arom). Testosterone is also converted into its bioactive metabolite dihydrotestosterone (DHT) by 5α-reductase. Sex steroid hormones are produced by various peripheral target tissues including the kidney, liver, and brain in addition to endocrine organs such as the testis or ovary in the recent research. For instance, steroidogenic enzymes expressed in skeletal muscle have been reported to locally synthesize sex steroid hormones from circulating dehydroepiandrosterone (DHEA) or testosterone in response to exercise. Thus, local steroidogenesis in skeletal muscle provides further evidence for the presence of an autocrine/paracrine system for sex steroid hormones and their roles in skeletal muscle function and adaptation. This review focuses on the steroidogenesis of skeletal muscle and discusses the physiological significance of the sex steroid hormones network of circulation and skeletal muscle.