研究者詳細 - 片山　敬章

論文 - 片山　敬章

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Effect of Intensive Interval Training during Unloading on Muscle Deoxygenation Kinetics 査読有り

Y. Furuichi, K. Masuda, H. Takakura, N. Hotta, K. Ishida, K. Katayama, S. Iwase, H. Akima

INTERNATIONAL JOURNAL OF SPORTS MEDICINE 30 巻 ( 8 ) 頁： 563 - 568 2009年8月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：GEORG THIEME VERLAG KG

The present study investigated the effects of intensive interval training during 20-day of unloading on local muscle oxygenation kinetics evaluated by near infrared spectroscopy technique (NIRS). Eleven adult men completed 20-day unloading and were divided into two groups; the control (CON) group and training (TR) group. The TR group engaged in exercise training sessions that consisted of one-legged submaximal cycle exercise using the unloaded leg at 60 similar to 80% of (V) over dotO(2peak) with intermittent rest periods, 25 min/day every other day. All Subjects performed isometric knee extension exercise at 50% of their maximum voluntary contraction force before and after unloading. NIRS Delta[deoxy-Hb/Mb] signal was recorded from m. vastus lateralis and was fitted to an exponential equation in order to determine the kinetics parameters. The time constant (tau) of the % Delta[deoxy-Hb/Mb] was unchanged in the TR group, while it significantly increased in the CON group after unloading(pre, 5.0 +/- 1.0; post, 7.4 +/- 1.0s). It is concluded that 20-day unloading increased the T, suggesting deterioration of capacity for oxidative phosphorylation and oxygen utilization in a skeletal muscle. Additionally, the preservation Of T in the TR group suggested that intensive interval training could have an impact on the maintenance of muscle oxidative metabolism during unloading.

DOI： 10.1055/s-0029-1202824

Web of Science

PubMed

Cycle ergometer exercise to counteract muscle atrophy during unilateral lower limb suspension.

Akima H, Hotta N, Sato K, Ishida K, Koike T, Katayama K

Aviation, space, and environmental medicine 80 巻 ( 7 ) 頁： 652-6 2009年7月

Effect of two durations of short-term intermittent hypoxia on ventilatory chemosensitivity in humans.

Katayama K, Ishida K, Iwasaki K, Miyamura M

European journal of applied physiology 105 巻 ( 5 ) 頁： 815-21 2009年3月

*Effect of two durations of short-term intermittent hypoxia on ventilatory chemosensitivity in humans. 査読有り

Katayama, K., K. Ishida, K. Iwasaki, and M. Miyamura.

Eur. J. Appl. Physiol. 105 巻頁： 483-491 2009年

記述言語：英語掲載種別：研究論文（学術雑誌）

The purpose of this study was to clarify the influence of duration of intermittent hypoxia per day on ventilatory chemosensitivity. Subjects were assigned to 3 different groups according to the duration of exposure to intermittent hypoxia (12.3% O2): A first group (H-1, n=6) was exposed to hypoxia for 1 hour per day, the second group (H-2, n=6) was exposed for 3 hours per day, and the third (C, n= 7) was used as control. Hypoxic and hypercapnic ventilatory responses (HVR and HCVR) were determined before and after 1 week of intermittent hypoxia. HVR was increased significantly (P<0.05) after intermittent hypoxia in both the H-1 and H-2 groups. However, there was no significant difference in magnitude of increased HVR between H-1 and H-2 groups. HCVR did not show any changes in all groups after intermittent hypoxia. These results suggest that 1 hour of daily exposure is as equally effective as 3 hours of daily exposure to severe hypoxia for a short period for enhancing ventilatory chemosensitivity to hypoxia.

DOI： 10.1007/s00421-008-0960-y

Effect of intensive interval cycling training during unilateral lower limb unloading on aerobic capacity Open Access

Keisho Katayama, Kohei Sato, Norio Hotta, Koji Ishida, Kohei Watanabe, Kazumi Masuda, Motohiko Miyachi, Teruhiko Koike, Hiroshi Akima

Japanese Journal of Physical Fitness and Sports Medicine 57 巻 ( 1 ) 頁： 84 2008年

Chronic intermittent hypoxia increases the CO2 reserve in sleeping dogs

Katayama Keisho, Smith Curtis A., Henderson Kathleen S., Dempsey Jerome A.

JOURNAL OF APPLIED PHYSIOLOGY 103 巻 ( 6 ) 頁： 1942-1949 2007年12月

Ventilatory and circulatory responses at the onset of dominant and non-dominant limb exercise.

Hotta N, Yamamoto K, Sato K, Katayama K, Fukuoka Y, Ishida K

European journal of applied physiology 101 巻 ( 3 ) 頁： 347 - 58 2007年10月

Effect of arterial oxygenation on quadriceps fatigability during isolated muscle exercise.

Katayama K, Amann M, Pegelow DF, Jacques AJ, Dempsey JA

American journal of physiology. Regulatory, integrative and comparative physiology 292 巻 ( 3 ) 頁： R1279-86 2007年3月

Intermittent hypoxia does not increase exercise ventilation at simulated moderate altitude. 査読有り

Katayama, K., K. Sato, N. Hotta, K. Ishida, K. Iwasaki, and M. Miyamura.

Int. J. Sports Med. 28 巻頁： 480-487 2007年

記述言語：英語掲載種別：研究論文（学術雑誌）

Recent human studies have shown that resting hypoxic ventilatory response (HVR), which is an index of ventilatory chemosensitivity to hypoxia, increased after short-term intermittent hypoxia at rest. In addition, intermittent hypoxia leads to increases in ventilation and arterial oxygen saturation (SaO (2)) during exercise at simulated high altitude, with the increase in ventilation correlated to the change in HVR. However, no study has been made to clarify the relationship between ventilatory chemosensitivity and the exercise ventilation at moderate altitude following intermittent hypoxia during a resting state. The purpose of the present study, therefore, was to elucidate whether intermittent hypoxia at rest induces the increase in ventilation during exercise at moderate altitude that is accompanied by an increase in hypoxic chemosensitivity. Eighteen trained male runners were assigned to three groups, i.e., the first hypoxic group (H-1 group, n = 6), the second hypoxic group (H-2 group, n = 6), and a control group (C group, n = 6). The hypoxic tent system was utilized for intermittent hypoxia, and the oxygen levels in the tent were maintained at 15.5 +/- 0.1 % (simulated 2500 m altitude) for the H-1 group and 12.3 +/- 0.2 % (simulated 4300 m altitude) for the H-2 group. The H-1 and H-2 groups spent 1 hour per day in the hypoxic tent for 1 week. Maximal and submaximal exercise tests while breathing 15.5 +/- 0.01 % O (2) (simulated altitude of 2500 m) were performed before and after intermittent hypoxia. Resting HVR was also determined in each subject using a progressive isocapnic hypoxic method. In the H-2 group, HVR increased significantly (p < 0.05) following intermittent hypoxia, while no change in HVR was found in the H-1 or C group. Neither ventilation nor SaO (2) during maximal and submaximal exercise at a simulated altitude of 2500 m were changed in either group after 1 hour per day for 1 week of intermittent hypoxia. These results suggest that the change i

DOI： 10.1055/s-2006-955895

*The effect of arterial oxygenation on quadriceps fatigability during isolated muscle exercise. 査読有り

Katayama, K., M. Amann, D. F. Pagelow, A. J. Jacques, and J. A. Dempsey.

Am. J. Physiol. Regul. Integr. Physiol. 292 巻頁： R1279-R1286 2007年

記述言語：英語掲載種別：研究論文（学術雑誌）

The effect of various levels of oxygenation on quadriceps muscle fatigability during isolated muscle exercise was assessed in six male subjects. Twitch force (Qtw) was assessed using supra-maximal magnetic femoral nerve stimulation. In Experiment I, maximal voluntary contraction (MVC) and Qtw of resting quadriceps muscle were measured in nomoxia [arterial O2 saturation (SpO2) = 98.4; NORM], acute-hypoxia (SpO2 = 74.6%; HYPO), and acute-hyperoxia (SpO2 = 100%; HYPER). No significant differences were found for MVC and Qtw among the three FIO2s. In Experiment II, the subjects performed three sets of nine, intermittent, isometric, unilateral, submaximal quadriceps contractions (62% MVC) while breathing each FIO2. Qtw was assessed before and after exercise, and myoelectrical activity of the vastus lateralis was obtained during exercise. The percent reduction of twitch force (potentiated Qtw) in HYPO (-27.0%) was significantly (P<0.05) greater than those in NORM (-21.4%) and HYPER (-19.9%). The increase in integrated electromyogram over the course of the nine contractions in HYPO (15.4%) was higher (P<0.05) than in NORM (7.2%) or HYPER (6.7%). These results demonstrate that quadriceps muscle fatigability during isolated muscle exercise is exacerbated in acute hypoxia, and these effects were independent of the relative exercise intensity.

DOI： 10.1152/ajpregu.00554.2006

Chronic intermittent hypoxia increases the CO2 reserve in sleeping dogs. 査読有り

Katayama, K., C. A. Smith, K. S. Henderson, and J. A. Dempsey.

J. Appl. Physiol. 103 巻頁： 1973-1978 2007年

Comments on Point:Counterpoint "Positive effects of intermittent hypoxia (live high:train low) on exercise performance are/are not mediated primarily by augmented red cell volume".

Katayama K

Journal of applied physiology (Bethesda, Md. : 1985) 99 巻 ( 6 ) 頁： 2460 2005年12月

Intensive cycle training with artificial gravity maintains muscle size during bed rest.

Akima H, Katayama K, Sato K, Ishida K, Masuda K, Takada H, Watanabe Y, Iwase S

Aviation, space, and environmental medicine 76 巻 ( 10 ) 頁： 923-9 2005年10月

Changes In Ventilatory Responses To Hypercapnia And Hypoxia After Intermittent Hypoxia In Trained Athletes

Katayama Keisho, Sato Kohei, Matsuo Hiroshi, Hotta Norio, Sun Zhihu, Ishida Koji, Iwasaki Ken-ichi, Miyamura Miharu

MEDICINE AND SCIENCE IN SPORTS AND EXERCISE 37 巻頁： S294-S294 2005年5月

Changes in ventilatory responses to hypercapnia and hypoxia after intermittent hypoxia in humans

Katayama K, Sato K, Matsuo H, Hotta N, Sun ZH, Ishida K, Iwasaki K, Miyamura M

RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY 146 巻 ( 1 ) 頁： 55-65 2005年3月

Vestibulo-cardiorespiratory responses at the onset of chair rotation in endurance runners. Open Access

Sato K, Katayama K, Katayama N, Hotta N, Ishida K, Miyamura M

The Japanese journal of physiology 55 巻 ( 1 ) 頁： 11-8 2005年2月

Effect of a repeated series of intermittent hypoxic exposures on ventilatory response in humans. 査読有り

Katayama, K.,H. Fujita, K. Sato, K. Ishida, K. Iwasaki, and M. Miyamura.

High Alt. Med. Biol. 6 巻頁： 50-59 2005年

*Changes in ventilatory responses to hypercapnia and hypoxia after intermittent hypoxia in humans. 査読有り

Katayama, K.,K. Sato, H. Matsuo, N. Hotta, Z. Sun, K. Ishida, K. Iwasaki, and M. Miyamura.

Respir. Physiol. Neurobiol. 146 巻頁： 55-65 2005年

記述言語：英語掲載種別：研究論文（学術雑誌）

The purpose of this study was to clarify the changes in hypercapnic and hypoxic ventilatory responses (HCVR and HVR) after intermittent hypoxia and following the cessation of hypoxic exposure. Twenty-nine males were assigned to one of four groups, i.e., a hypoxic (EX1-H, n=7) or a control (EX1-C, n=7) group in Experiment 1, and a hypoxic (EX2-H, n=8) or a control (EX2-C, n=7) group in Experiment 2. In each experiment, the hypoxic tent system was utilized for intermittent hypoxia, and the oxygen levels in the tent were maintained at 12.3+/-0.2%. In Experiment 1, the EX1-H group spent 3 h/day in the hypoxic tent for 1 week. HCVR and HVR were determined before and after 1 week of intermittent hypoxia, and again 1 and 2 week after the cessation of hypoxic exposure. In Experiment 2, the subjects in the EX2-H group performed 3 h/day for 2 weeks in intermittent hypoxia. HCVR and HVR tests were carried out before and after intermittent hypoxia, and were repeated again after 2 weeks of the cessation of hypoxic exposure. The slope of the HCVR in the EX1-H group did not show a significant increase after 1 week of intermittent hypoxia, while HCVR in the EX2-H group increased significantly after 2 weeks of intermittent hypoxia. The HCVR intercept was unchanged following 1 or 2 weeks of intermittent hypoxia. There was a significant increase in the slope of the HVR after 1 and 2 weeks of intermittent hypoxia. The increased HCVR and HVR returned to pre-hypoxic levels after 2 weeks of the cessation of hypoxia. These results suggest that 3 h/day for 2 weeks of intermittent hypoxia leads to an increase in central hypercapnic ventilatory chemosensitivity, which is not accompanied by a re-setting of the central chemoreceptors, and that the increased hypercapnic and hypoxic chemosensitivities are restored within 2 weeks after the cessation of hypoxia.

DOI： 10.1016/j.resp.2004.11.007

Acceleration with exercise during head-down bed rest preserves upright exercise responses.

Katayama K, Sato K, Akima H, Ishida K, Takada H, Watanabe Y, Iwase M, Miyamura M, Iwase S

Aviation, space, and environmental medicine 75 巻 ( 12 ) 頁： 1029-35 2004年12月

Ventilatory and heart rate responses at the onset of chair rotation in man. Open Access

Miyamura M, Ishida K, Katayama K, Shima N, Matsuo H, Sato K

The Japanese journal of physiology 54 巻 ( 5 ) 頁： 499-503 2004年10月

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