スポーツ健康学科

宮本 忠吉

ミヤモト タダヨシ  (Tadayoshi Miyamoto)

基本情報

所属
大阪産業大学 スポーツ健康学部スポーツ健康学科 教授
学位
博士(学術)(大阪市立大学)

研究者番号
40294136
ORCID ID
 https://orcid.org/0000-0001-5504-6119
J-GLOBAL ID
200901034436034369
researchmap会員ID
6000015757

外部リンク

学歴

 1

論文

 144
  • 嶋田 愛, フィーリー 真利奈, 伊藤 剛, 仲田 秀臣, 大槻 伸吾, 宮本 忠吉
    生体医工学 62(1) 22-30 2024年3月10日  査読有り
  • Toru Kawada, Tadayoshi Miyamoto, Masafumi Fukumitsu, Keita Saku
    American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 326(2) R121-R133 2024年2月1日  査読有り
    Although Gaussian white noise (GWN) inputs offer a theoretical framework for identifying higher-order nonlinearity, an actual application to the data of the neural arc of the carotid sinus baroreflex did not succeed in fully predicting the well-known sigmoidal nonlinearity. In the present study, we assumed that the neural arc can be approximated by a cascade of a linear dynamic (LD) component and a nonlinear static (NS) component. We analyzed the data obtained using GWN inputs with a mean of 120 mmHg and standard deviations (SDs) of 10, 20, and 30 mmHg for 15 min each in anesthetized rats (n = 7). We first estimated the linear transfer function from carotid sinus pressure to sympathetic nerve activity (SNA) and then plotted the measured SNA against the linearly predicted SNA. The predicted and measured data pairs exhibited an inverse sigmoidal distribution when grouped into 10 bins based on the size of the linearly predicted SNA. The sigmoidal nonlinearity estimated via the LD-NS model showed a midpoint pressure (104.1 ± 4.4 mmHg for SD of 30 mmHg) lower than that estimated by a conventional stepwise input (135.8 ± 3.9 mmHg, P < 0.001). This suggests that the NS component is more likely to reflect the nonlinearity observed during pulsatile inputs that are physiological to baroreceptors. Furthermore, the LD-NS model yielded higher R2 values compared with the linear model and the previously suggested second-order Uryson model in the testing dataset.NEW & NOTEWORTHY We examined the input-size dependence of the baroreflex neural arc transfer characteristics during Gaussian white noise inputs. A linear dynamic-static nonlinear model yielded higher R2 values compared with a linear model and captured the well-known sigmoidal nonlinearity of the neural arc, indicating that the nonlinear dynamics contributed to determining sympathetic nerve activity. Ignoring such nonlinear dynamics might reduce our ability to explain underlying physiology and significantly limit the interpretation of experimental data.
  • Marina Feeley, Go Ito, Shogo Tsubota, Toru Sawai, Hideomi Nakata, Shingo Otsuki, Tadayoshi Miyamoto
    Advanced Biomedical Engineering 13 35-42 2024年  査読有り
    Background: Alterations in central blood volume (CBV) play a pivotal role in the functionality of the respiratory and circulatory systems. This study elucidates the adaptive changes in respiration, cerebral circulation, and cardiovascular function in response to orthostatic stress in male volleyball players compared to healthy non-athletes. The athletes’ unique physiological adaptability may help them cope with the frequent CBV changes related to their sports activities. Methods: Fourteen male university students participated in this study; seven were volleyball players and seven were non-athletes. Participants underwent a maximal ramp exercise test and a lower body negative pressure (LBNP) test conducted to examine the cardiorespiratory response under LBNP and no-LBNP conditions. Respiratory, metabolic, hemodynamic, and cardiac measurements were collected and analyzed. Results: Volleyball players (Ath group) were significantly taller and exhibited higher maximal oxygen uptake (VO2max) and maximum work rate compared to non-athletes (Non-Ath group). Under the LBNP condition, end-tidal CO2 partial pressure (PETCO2) decreased by 4.1% in the Non-Ath group, but was maintained stable in the Ath group. The CBV reduction rate due to LBNP was notably less in the Ath group (−12.5%) compared to the Non-Ath group (−24.5%). In all participants, a significant correlation was observed between the CBV and PETCO2 reduction rates. However, cerebral blood flow and cardiovascular responses to LBNP load did not differ between the two groups. Conclusion: Male volleyball players demonstrate distinctive adaptability in response to orthostatic stress, specifically in maintaining stable PETCO2 and attenuating CBV reduction rate under LBNP load. These findings suggest that the sport-specific training in volleyball may induce some protective mechanisms against abrupt changes in CBV, although cerebral blood flow and cardiovascular responses appear unaffected. Further research is warranted to understand the underlying mechanisms of these adaptations.
  • Go Ito, Marina Feeley, Toru Sawai, Hideomi Nakata, Shingo Otsuki, Hidehiro Nakahara, Tadayoshi Miyamoto
    Frontiers in physiology 15 1227316-1227316 2024年  査読有り
    Purpose: High-intensity interval training (HIIT) may induce training-specific physiological adaptations such as improved respiratory and cardiovascular adjustments before and after the onset of high-intensity exercise, leading to improved exercise performance during high-intensity exercise. The present study investigated the effects of HIIT on time-dependent cardiorespiratory adjustment during maximal exercise and before and after initiation of high-intensity exercise, as well as on maximal exercise performance. Methods: 21 healthy male college students were randomly assigned to HIIT group (n = 11) or control group (n = 10). HIIT group performed training on a cycle ergometer once a week for 8 weeks. The training consisted of three bouts of exercise at 95% maximal work rate (WRmax) until exhaustion. Before and after the HIIT program, dynamic cardiorespiratory function was investigated by ramp and step exercise tests, and HIIT-induced cardiac morphological changes were assessed using echocardiography. Results: HIIT significantly improved not only maximal oxygen uptake and minute ventilation, but also maximal heart rate (HR), systolic blood pressure (SBP), and time to exhaustion in both exercise tests (p < 0.05). Time-dependent increases in minute ventilation (VE) and HR before and at the start of exercise were significantly enhanced after HIIT. During high-intensity exercise, there was a strong correlation between percent change (from before to after HIIT program) in time to exhaustion and percent change in HRmax (r = 0.932, p < 0.001). Furthermore, HIIT-induced cardiac morphological changes such as ventricular wall hypertrophy was observed (p < 0.001). Conclusion: We have demonstrated that HIIT at 95% WRmax induces training-specific adaptations such as improved cardiorespiratory adjustments, not only during maximal exercise but also before and after the onset of high-intensity exercise, improvement of exercise performance mainly associated with circulatory systems.
  • フィーリー 真利奈, 伊藤 剛, 澤井 亨, 仲田 秀臣, 大槻 伸吾, 宮本 忠吉
    体力科学 72(3) 267-268 2023年6月  

MISC

 156

書籍等出版物

 24

講演・口頭発表等

 210

所属学協会

 6

共同研究・競争的資金等の研究課題

 34

研究テーマ

 1
  • 研究テーマ
    統合的枠組みによる呼吸循環調節系の制御機構の解明とその応用研究
    研究期間(開始)
    1994/04/01

免許・資格

 2
  • 免許・資格名
    高等学校教諭専修免許保健体育
    取得年月日
    1992/03/01
    概要
    大阪府教育委員会
  • 免許・資格名
    中学校教諭専修免許保健体育
    取得年月日
    1992/03/01
    概要
    大阪府教育委員会