• Title/Summary/Keyword: Trained runner

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Runner Training Angle Affects Growth of Runners in 'Seolhyang' and 'Maehyang' Strawberries ('설향'과 '매향' 딸기에서 런너 유인 각도가 런너의 생장에 미치는 영향)

  • Zhao, Jin;Li, Yali;Park, Yoo Gyeong;Hu, Jiangtao;Jeong, Byoung Ryong
    • Journal of Bio-Environment Control
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    • v.29 no.3
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    • pp.231-238
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    • 2020
  • Strawberry (Fragaria × ananassa Duch.), a herbaceous perennial crop, is a popular fruit crop with high economical and nutritive values. This study was conducted to investigate the effect of the runner training angle (RTA) on the length of internodes and number of runners produced in strawberry 'Seolhyang' and 'Maehyang' in an attempt to achieve a higher production rate of runner plants and increase the propagation efficiency. Runners were trained for 30 days to grow at an angle of 0° (vertically upward), 45°, 90° (horizontal), 135°, or 180° (hanging down) from the upward vertical axis. The experiment was carried out in a glasshouse with 29/20℃ day/night temperatures, an average light intensity of 450 μmol·m-2·s-1 PPFD coming from the sun, and a natural photoperiod of 12 hours. For both 'Seolhyang' and 'Maehyang', the RTA affected number and length of runners, and number and fresh and dry weights of runner plants. Training at an angle of 135° or 180° shortened length of runners and internodes in 'Seolhyang'. These RTAs also produced runner plants with the lowest fresh and dry weights in both cultivars. The RTA did not affect the runner diameter, but affected the runner morphology in both cultivars. As compared to a RTA of 135°, a 180° RTA increased number of runner plants produced, making it the most proliferative RTA.

Sweating by Exercise Controls Body Temperature through Increase of Interleukin-1beta

  • Bae, Jun-Sang;Shin, Young-Oh;Lee, Jeong-Beom;Seok, Hyun;Min, Young-Ki;Yang, Hun-Mo
    • The Korean Journal of Physiology and Pharmacology
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    • v.10 no.5
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    • pp.231-234
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    • 2006
  • This study was designed to investigate the expression and production of interleukin-1beta $(IL-1{\beta})$ in human peripheral blood of trained runners and untrained controls after temporary moderate intensity exercise. Male long-distance trained runners (TR) and untrained sedentary control subjects (SED) ran for 1 h at 70% of heart rate reserve (HRR). $IL-1{\beta}$ gene and protein expressions were significantly higher in TR than those with SED at all 3 intervals examined independently. Significant increases in total sweat volume and oral temperature were observed after exercise in both groups, however, there were some differences between the groups. We conclude, therefore, that sweating due to exercise is associated with increase of $IL-1{\beta}$ and it is correlated with decrease of oral temperature.

Comparison of Interleukin-8 Levels in Long-Distance Runners and Healthy Sedentary Non-Athletic Control Subjects

  • Shin, Young-Oh;Bae, Jun-Sang;Min, Ji-Won;Lee, Jeong-Beom;Kim, Jung-Kyu;Song, Young-Ju;Yang, Hun-Mo;Min, Young-Ki
    • The Korean Journal of Physiology and Pharmacology
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    • v.11 no.6
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    • pp.263-267
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    • 2007
  • We have previously demonstrated that the level of leukocytes and neutrophils significantly increased immediately and 30 min after exercise. Interleukin-8 (IL-8) is an inflammatory cytokine that acts as a chemokine on neutrophils. In the present study, we evaluated the correlation between the number of neutrophils and leukocytes, and between the number of neutrophils and plasma IL-8 level. Long-distance trained runners (TRs, n = 10) and untrained sedentary control subjects (SEDs, n = 10) ran for one hour at 70% of heart rate reserve. In the TR, the number of neutrophils correlated significantly with the number of leukocytes in the blood. However, there was no correlation between the number of neutrophils and the plasma IL-8 concentration in both groups. Expressions of IL-8 protein and mRNA were markedly higher in the TRs as compared to the SEDs at three time intervals (pre-exercise, immediately after exercise, and post exercise). In conclusion, our results show that 1) the neutrophil level was dependent on the level of leukocytes 2) there was no correlation between the neutrophils count and plasma IL-8 concentration and 3) a higher plasma IL-8 level in athletes may be a unique characteristic of intensive training.