http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Kevin Boldt (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Kevin Boldt,Stela Mattiello,Venus Joumaa,Jeannine Turnbull,Paul W.M. Fedak,Walter Herzog 한국운동영양학회 2021 Physical Activity and Nutrition (Phys Act Nutr) Vol.25 No.2
[Purpose] The purpose of this study was to investigate the effects of a high-fat high-sucrose (HFHS) diet on previously reported adaptations of cardiac morphological and contractile properties to resistance training. [Methods] Twelve-week-old rats participated in 12-weeks of resistance exercise training and consumed an HFHS diet. Echocardiography and skinned cardiac muscle fiber bundle testing were performed to determine the structural and mechanical adaptations. [Results] Compared to chow-fed sedentary animals, both HFHS- and chow-fed resistance-trained animals had thicker left ventricular walls. Isolated trabecular fiber bundles from chow-fed resistance-trained animals had greater force output, shortening velocities, and calcium sensitivities than those of chow-fed sedentary controls. However, trabeculae from the HFHS resistance-trained animals had greater force output but no change in unloaded shortening velocity or calcium sensitivity than those of the chow-fed sedentary group animals. [Conclusion] Resistance exercise training led to positive structural and mechanical adaptations of the heart, which were partly offset by the HFHS diet.
-
Kevin Boldt,Venus Joumaa,Jeannine Turnbull,Paul W.M. Fedak,Walter Herzog 한국운동영양학회 2022 Physical Activity and Nutrition (Phys Act Nutr) Vol.26 No.1
[Purpose] Aerobic exercise training results in distinct structural and mechanical myocardial adaptations. In skeletal muscle, whey protein supplementation is effective in enhancing muscle adaptation following resistance exercise. However, it is unclear whether cardiac adaptation to aerobic exercise can be enhanced by systematic protein supplementation. [Methods] Twelve-week-old rats were assigned to 12 weeks of either sedentary or aerobic exercise with either a standard (Sed+Standard, Ex+Standard) or high-protein (Sed+Pro, Ex+Pro) diet. Echocardiography was used to measure cardiac structural remodeling and performance. Skinned cardiac fiber bundles were used to determine the active and passive stress properties, maximum shortening velocity, and calcium sensitivity. [Results] Aerobic training was characterized structurally by increases in ventricle volume (Ex+Standard, 19%; Ex+Pro, 29%) and myocardial thickness (Ex+Standard, 26%; Ex+Pro, 12%) compared to that of baseline. Skinned trabecular fiber bundles also had a greater unloaded shortening velocity (Sed+Standard, 1.04±0.05; Sed+Pro, 1.07±0.03; Ex+Standard, 1.16±0.04; Ex+Pro, 1.18±0.05 FL/s) and calcium sensitivity (pCa50: Sed+Standard, 6.04±0.17; Sed+Pro, 6.08±0.19; Ex+Standard, 6.30±0.09; Ex+Pro, 6.36±0.12) in trained hearts compared to that of hearts from sedentary animals. However, the addition of a high-protein diet did not provide additional benefits to either the structural or mechanical adaptations of the myocardium. [Conclusion] Therefore, it seems that a high-whey-protein diet does not significantly enhance adaptations of the heart to aerobic exercise in comparison to that of a standard diet.
-
S. K. Han(한상규),Kevin R Boldt,K. J. Chun(전경진),Walter Herzog,Venus Joumaa Korean Society for Precision Engineering 2021 한국정밀공학회 학술발표대회 논문집 Vol.2021 No.11월
Botulinum toxin type A (BTX-A) has been widely used for the treatment of muscle stiffness and hyperactivity, such as spasticity and dystonia in patients post-stroke or children with Cerebral Palsy. However, BTX-A injection has been shown to cause muscle atrophy, fat infiltration, fibrosis, and decreased force output in target muscles, but its potential effects on the contractile machinery and force production on the cellular level remain unknown. The aim of this study was to investigate the effects of BTX-A injections on the mechanical properties of skinned fibres from rabbit paraspinal muscles. Nineteen-month-old rabbits received either saline or BTX-A injections into the paraspinal muscles, equally distributed along the left and right sides of the spine at T12, L1, and L2 for five times during 24 weeks. Fibres were tested for their active and passive force-length relationships, unloaded shortening velocity and myosin heavy chain isoforms. BTX-A injections led to significant fat infiltration within the injected muscles and a greater proportion of IIa to IIx fibres. Single fast fibres from BTX-A injected animals had lower active force and unloaded shortening velocity compared to fibres from saline-injected control animals. Force and velocity properties were not affected by BTX-A injections for the slow fibres.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
