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37 results on '"Yamanaka, Ryo"'

2. Effects of Small Group Discussion: Case Study of Community Disaster Risk Management in Japan

Author

Chosokabe, Madoka, Tsuguchi, Yukino, Sakakibara, Hiroyuki, Nakayama, Takanobu, Mine, Shota, Kamiya, Daisuke, Yamanaka, Ryo, Miyaguni, Toshiaki, van der Aalst, Wil, Series editor, Mylopoulos, John, Series editor, Rosemann, Michael, Series editor, Shaw, Michael J., Series editor, Szyperski, Clemens, Series editor, Kamiński, Bogumił, editor, Kersten, Gregory E., editor, and Szapiro, Tomasz, editor

Published
2015
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3. Effect of Resistance Training of Psoas Major in Combination With Regular Running Training on Performance in Long-Distance Runners.

Author

Yamanaka, Ryo, Wakasawa, Shinya, Yamashiro, Koya, Kodama, Naoki, and Sato, Daisuke

Subjects
PSOAS muscles, RESISTANCE training, LONG-distance running, EFFECT sizes (Statistics), ATHLETES, T-test (Statistics), PRE-tests & post-tests, LACTATES, DATA analysis software, SPRINTING
Abstract

Purpose: The study determined whether the increase in the cross-sectional area (CSA) of psoas major, which is known as a hip-flexion muscle, by resistance training combined with running training improves the performance of long-distance runners. Methods: Subjects were 8 well-trained male long-distance runners. The personal best time in a 5000-m race was 15:10.0 (0:20.5) (mean [SD]). Each subject performed resistance training twice per week with running training for 12 weeks. The authors used 3 resistance training regimens that would train the hip flexor muscles. Training intensity was a maximum of 10 repetitions. The training amount was 3 sets × 10 times during the first 4 weeks followed by 4 sets × 10 times during the last 8 weeks. The authors measured the CSA of psoas major using magnetic resonance imaging and the performance of long-distance runners using a constant velocity running test before (pre) and after (post) the training term. Results: The combination training significantly (P <.01, d = 0.34) increased the CSA of psoas major (pre: 16.2 [1.5] cm2, post: 16.7 [1.4] cm2) and significantly (P <.01, d = 1.41) improved the duration of the constant velocity running test (pre: 500 [108] s, post: 715 [186] s). Moreover, multiple regression analysis showed that the pre to post change in the duration of the constant velocity exercise was significantly correlated with the change in CSA of the psoas major. Conclusion: The authors suggest that resistance training of psoas major with running training is correlated with an improvement in the performance of long-distance runners. [ABSTRACT FROM AUTHOR]

Published
2021
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18. Resarch of Plumonary Ventilatory Regulation to Intense Exercise

Author

Yamanaka, Ryo

Subjects
努力感, セントラルモーターコマンド, Ventilatory resposense, 肺換気応答, Central motor command, Intense exercise, Effort sense, 高強度運動
Abstract

本研究の目的は，高強度運動に対する肺換気応答の調節の機序を検討することであり，その目的を達成するために3つの実験を実施した。3つの実験から，以下の結果を得た。1）高強度運動に対する肺換気応答には，血液 pH の低下よりむしろ努力感が強く関与している。2）努力感に依存した肺換気応答には，必ずしも活動肢に対するセントラルモーターコマンドを必要としない。すなわち，努力感は，行動性呼吸調節因子としてIE に対する肺換気応答に関与している。3）IE 終了後の安静回復時における肺換気動態には，脚の努力感のような局所的感覚ではなく，多様な要因が関与する全身的な主観的感覚が影響している可能性が高い。, The purpose of this study was to determine the mechanism of pulmonary ventilatory regulation to intense exercise. I conducted the three experiments to accomplish the purpose. As a result of the experiments，I showed the three important findings. 1）Ventilatory response to intense exercise was affected by effort sense rather than the decrease in blood pH. 2）Ventilatory response depended on effort sense does not necessarily require central motor command to active muscles. Effort sense was concerned with pulmonary ventilatory response to intense exercise as a behavioral factor of ventilatory regulation. 3）Ventilatory response during recovery after intense exercise might not be influenced by local senses such as effort sense of legs，but influenced by general subjective sense involved in various factors.

Published
2016

19. Relationships between running performance and the cross–sectional area of the psoas major, and peak oxygen uptake in elite junior long–distance runners

Author

YAMANAKA, Ryo, MATSUBAYASHI, Takeo, SAEKI, TETSURO, ENOMOTO, Yasushi, YAMAZAKI, Kazuhiko, and SUGITA, Masaaki

Subjects
running economy, long–distance runner, peak oxygen uptake, psoas major, long-distance runner
Abstract

The purpose of this study was to examine the relationships between running performance and the cross–sectional area of the psoas major, peak oxygen uptake, and running economy in male junior long–distance runners. The subjects were 37 male junior athletes who achieved good records in interscholastic athletic competition during 5 years (2011–2015). Their seasonal best times in a 5,000 m race (5,000m–SB) were 14:04.11 ± 0:07.25 (13:53.64–14:16.15). In a multiple regression analysis, 5,000m–SB was statistical significantly correlated with the cross–sectional area of psoas major (16.0 ± 1.7 cm2) measured on magnetic resonance imaging and peak oxygen uptake (4.25 ± 0.36 l min-1 [76.9 ± 5.8 ml min-1 kg-1]) during a lactate curve test comprising five stages. However, 5,000m–SB was not related to oxygen uptake at the work–load which was less than the load at the lactate threshold estimated by using the lactate curve test results. These results suggest that a high volume of the psoas major, the largest hip–flexor muscle, and peak oxygen uptake are among the important factors for junior long–distance runner performance.

Published
2016

31. Revamping Pace Distribution: A Case Study on Elevating the Men's 400 m Track and Field Japanese National Record After 32 Years

Author

Chiba, Yoshihiro, Sato, Kentaro, Yoshimoto, Takaya, Ohnuma, Hayato, Yamanaka, Ryo, Takahashi, Kyohei, Kobayashi, Kai, Matsubayashi, Takeo, and Takai, Yohei

Abstract

Chiba, Y, Sato, K, Yoshimoto, T, Ohnuma, H, Yamanaka, R, Takahashi, K, Kobayashi, K, Matsubayashi, T, and Takai, Y. Revamping pace distribution: A case study on elevating the men's 400 m track and field Japanese national record after 32 years. J Strength Cond ResXX(X): 000–000, 2024—Many studies have investigated the 400-m sprint, and the optimal pacing strategy is subject to debate. Little information is available regarding the effects of changes in the pacing strategy on running speed and spatiotemporal variables in the official 400-m race. This case study analyzed changes in running speed and spatiotemporal variables of a Japanese elite long sprinter who set a new Japanese national record in the 400-m race by modifying his pace distribution based on the analysis of his previous races and the performances of world-class long sprinters. To revamp his pace distribution, 25 preceding races (ranging from 45.47 to 46.95 seconds) were analyzed, spanning from June 2015 to June 2023. The independent variables were the 50-m split time, average running speed, percentage of the 50-m split time relative to the 400-m record, step length, and step frequency. K.S. broke his own record by modifying the pacing distribution based on the development of his previous race and the world-class long sprinters. The modified pacing strategy increased running speed in the 200- to 300-m section. Step lengths were longer throughout the 400 m, and step frequencies were higher in the last 200 m than before the alteration in the pace distribution. Modifying the pacing strategy from leading to driving may enhance the personal records of long sprinters. This improvement is attributed to the maintenance of longer step lengths over the entire 400-m range and an increase in the step frequency in the last 200 m.

Published
2024
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32. Relationship between motor corticospinal excitability and ventilatory response during intense exercise

Author

1000000352500, Yunoki, Takahiro, Matsuura, Ryouta, Yamanaka, Ryo, Afroundeh, Roghayyeh, Lian, Chang-shun, Shirakawa, Kazuki, Ohtsuka, Yoshinori, Yano, Tokuo, 1000000352500, Yunoki, Takahiro, Matsuura, Ryouta, Yamanaka, Ryo, Afroundeh, Roghayyeh, Lian, Chang-shun, Shirakawa, Kazuki, Ohtsuka, Yoshinori, and Yano, Tokuo

Abstract

Purpose Effort sense has been suggested to be involved in the hyperventilatory response during intense exercise (IE). However, the mechanism by which effort sense induces an increase in ventilation during IE has not been fully elucidated. The aim of this study was to determine the relationship between effort-mediated ventilatory response and corticospinal excitability of lower limb muscle during IE. Eight subjects performed 3 min of cycling exercise at 75-85 % of maximum workload twice (IE1st and IE2nd). IE2nd was performed after 60 min of resting recovery following 45 min of submaximal cycling exercise at the workload corresponding to ventilatory threshold. Vastus lateralis muscle response to transcranial magnetic stimulation of the motor cortex (motor evoked potentials, MEPs), effort sense of legs (ESL, Borg 0-10 scale), and ventilatory response were measured during the two IEs. The slope of ventilation (l/min) against CO2 output (l/min) during IE2nd (28.0 +/- 5.6) was significantly greater than that (25.1 +/- 5.5) during IE1st. Mean ESL during IE was significantly higher in IE2nd (5.25 +/- 0.89) than in IE1st (4.67 +/- 0.62). Mean MEP (normalized to maximal M-wave) during IE was significantly lower in IE2nd (66 +/- 22 %) than in IE1st (77 +/- 24 %). The difference in mean ESL between the two IEs was significantly (p < 0.05, r = -0.82) correlated with the difference in mean MEP between the two IEs. The findings suggest that effort-mediated hyperventilatory response to IE may be associated with a decrease in corticospinal excitability of exercising muscle.

Published
2016

36. Tissue distribution of renadirsen sodium, a dystrophin exon-skipping antisense oligonucleotide, in heart and diaphragm after subcutaneous administration to cynomolgus monkeys.

Author

Yamamura, Naotoshi, Takakusa, Hideo, Asano, Daigo, Watanabe, Kyoko, Shibaya, Yukari, Yamanaka, Ryo, Fusegawa, Keiichi, Kanda, Akira, Nagase, Hiroyuki, Takaishi, Kiyosumi, Koizumi, Makoto, Takeshima, Yasuhiro, and Matsuo, Masafumi

Subjects
*QUADRICEPS muscle, *TIBIALIS anterior, *NUCLEIC acids, *INTRAVENOUS therapy, *DYSTROPHIN
Abstract

AbstractThe pharmacokinetics and tissue distribution of renadirsen sodium, a dystrophin exon-skipping phosphorothioate-modified antisense oligonucleotide with 2’-O,4’-C-ethylene-bridged nucleic acid (ENA), after subcutaneous or intravenous administration to cynomolgus monkeys were investigated. The plasma concentration of renadirsen after subcutaneous administration at 1, 3, and 10 mg/kg increased with the dose. The absolute bioavailability at 3 mg/kg after subcutaneous administration was calculated as 88.6%, and the time to reach maximum plasma concentration of renadirsen was within 4 h, indicating the efficient and rapid absorption following subcutaneous administration. The exposure of muscle tissues to renadirsen was found to increase with repeated dosing at 6 mg/kg, and higher exposure was observed in the diaphragm and heart than in the quadriceps femoris and anterior tibialis muscles. Renadirsen achieved more exon 45-skipped dystrophin mRNA in the diaphragm and heart than in the quadriceps femoris and anterior tibialis muscles. Renadirsen also showed a cumulative skipping effect in a repeated-dose study. The findings on exon 45-skipped dystrophin mRNA in these muscle tissues were consistent with the concentration of renadirsen in these tissues. Because it is not feasible to directly evaluate drug concentration and exon skipping in the heart and diaphragm in humans, the pharmacokinetics and pharmacodynamics of renadirsen in these tissues in monkeys are crucial for the design and interpretation of clinical settings. [ABSTRACT FROM AUTHOR]

Published
2024
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