• 한국운동역학회지
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• 제18권4호
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• pp.21-30
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• 2008

본 연구에서는 신장성 수축운동에 의한 미세 근수축 요소 손강 이론(Morgan & Allen, 1999)을 검증하고자 신장성 수축운동의 범위에 따른 골격근의 기계학적 특성 변화에 주안점을 두어 실험 연구를 수행 하였다. 12명의 건강한 피험자가 최대 발목 족배굴곡근의 신장성 수축운동을 수행하였고, 운동수행 전에 최대 등척성 발목 족배굴곡 모멘트-각도 관계로부터 최적 발목 각도의 변화를 측정하였다. 신장성 수축운동 추 최적 발목 각도 변화는 신장성 수축운동의 범위와 상관없이 근육의 길이가 긴 쪽으로 변화를 가져왔다(4도, p<.05). 따라서 본 연구의 결과는 현재 많은 연구에서 거론되고 있는 신장성 수축에 의한 근력 저하 및 지연성 근육통의 촉발 기전인 신장성 수축에 의한 미세 근수축 요소 손강 이론의 부합하지 않으며, 이 현상을 설명할 새로운 이론 개발을 위한 후속연구의 필요성을 제기한다.

• 운동영양학회지
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• 제24권2호
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• pp.6-10
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• 2020

[Purpose] Milk is a commonly ingested post-exercise recovery protein source. Casein protein, found in milk, is characterized by its slow digestion and absorption. Recently, several studies have been conducted with a focus on how pre-sleep casein protein intake could affect post-exercise recovery but our knowledge of the subject remains limited. This review aimed at presenting and discussing how pre-sleep casein protein ingestion affects post-exercise recovery and the details of its potential effector mechanisms. [Methods] We systematically reviewed the topics of 1) casein nutritional characteristics, 2) pre-sleep casein protein effects on post-exercise recovery, and 3) potential effector mechanisms of pre-sleep casein protein on post-exercise recovery, based on the currently available published studies on pre-sleep casein protein ingestion. [Results] Studies have shown that pre-sleep casein protein ingestion (timing: 30 minutes before sleep, amount of casein protein ingested: 40-48 g) could help post-exercise recovery and positively affect acute protein metabolism and exercise performance. In addition, studies have suggested that repeated pre-sleep casein protein ingestion for post-exercise recovery over a long period might also result in chronic effects that optimize intramuscular physiological adaptation (muscle strength and muscle hypertrophy). The potential mechanisms of pre-sleep casein protein ingestion that contribute to these effects include the following: 1) significantly increasing plasma amino acid availability during sleep, thereby increasing protein synthesis, inhibiting protein breakdown, and achieving a positive protein balance; and 2) weakening exercise-induced muscle damage or inflammatory responses, causing reduced muscle soreness. Future studies should focus on completely elucidating these potential mechanisms. [Conclusion] In conclusion, post-exercise ingestion of at least 40 g of casein protein, approximately 30 minutes before sleep and after a bout of resistance exercise in the evening, might be an effective nutritional intervention to facilitate muscle recovery.

• 대한임상전기생리학회지
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• 제7권1호
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• pp.1-6
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• 2009

Purpose : We investigated the effects of microcurrent(MC) electrical stimulation on each intensity($100{\mu}A,\;200{\mu}A,\;500{\mu}A$ - 30pps frequency was same) on delayed onset muscle soreness(DOMS). Methods : Subjects were assigned randomly divided into three groups of eight for three different treatment protocoals($100{\mu}A,\;200{\mu}A,\;500{\mu}A$-experimental groups). Twenty-four healthy males and females subjects were participated in this study. All subjects performed eccentric exercise of elbow flexor(biceps brachii) until exhausted. The measured items of elbow flexor muscle strength were Nicholas Manual Muscle Taster(NMMT). The measured items of elbow joint range of motion ROM) were Goniometer. The measured items of elbow flexor muscle pain were visual analogue scale(VAS). Treatment were applied at 30 minute exercise after and again at 24 hours and at 48 hours and at 72 hours after. Measurements were taken after treatment. Analysis of Results using repeated measures analysis of variance(ANOVA) and post hoc tests were as follows: two-way ANOVA with repeated measurement for muscle strength, flexion ROM, extension ROM and VAS. Results : This results showed eccentric exercise casused DOMS, DOMS response to eccentric exercise were reduces by microcurrent therapy. DOMS was significant decreased at $100{\mu}A,\;200{\mu}A,\;500{\mu}A$. Muscle strength was significant difference at all intensity. Elbow flexion ROM was significant difference at all intensity but elbow extension ROM was insignificant difference at all intensity. VAS score was significant difference at $100{\mu}A$ and $500{\mu}A$ but insignificant difference at $200{\mu}A$. All experimental groups showed insignificant difference with all intensity MENS. Conclusion : These findings indicate that microcurrent therapy is had effect on recovery from exercise induced muscle damage. In our's suggestion, microcurrent therapy is particularly more appropriate therapeutic modality.

• 대한물리치료과학회지
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• 제28권3호
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• pp.30-41
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• 2021

Background: The purpose of this study was to investigate the effects of WBC on the pressure pain threshold, CK and LDH after exercise-induced muscle injury. Design: A Randomized Controlled Trial. Methods: In this study, these subjects were assigned into three groups, a control group (n=10), experiment group I (n=10) and experiment group II (n=10). The subjects in experimental group I were intervened by WBC (-130℃, 3 minutes) before induced EIMD, experimental group II were intervened by WBC (-130℃, 3 minutes) after induced EIMD and control group weren't by any intervened after induced EIMD. Results: First, In the comparison of the PPT, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the PPT of experimental group II was significantly larger than those of other groups (p<.01). Second, In the comparison of the CK, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the CK of experimental group II was significantly smaller than those of other groups (p<.001). Third, In the comparison of the LDH, there were significant variations with the lapse the time in three groups (p<.01) and there was a significant interaction of time and group (p<.001). In the among group comparison, the LDH of experimental group II was significantly smaller than those of other groups (p<.001). Conclusion: The above results revealed that the WBC intervention after an exercise had a positive effect of muscle function after EIMD.

• Preventive Nutrition and Food Science
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• 제16권3호
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• pp.278-281
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• 2011

In this study, coffee was shown to effectively inhibit L6 muscle cell death and ATP reduction induced by hydrogen peroxide damage. Additionally, two weeks of oral administration of 7 mg/kg coffee extracts to mice resulted in a 33% increase in treadmill running time relative to that seen in the distilled water administered group. Blood analysis showed decreased lactate content, which was increased by exercise. Thus, these data suggest that coffee intake may enhance exercise capacity and inhibit damage due to excessive exercise.

• Journal of Applied Biological Chemistry
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• 제56권1호
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• pp.1-3
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• 2013

본 연구결과에서 홍경천 추출물은 L6 근육세포에서 산화적 손상으로 인한 세포사멸과 ATP 생성량 감소를 유의적으로 억제하였을 뿐만 아니라 마우스에 2주간 200 mg/kg 농도로 경구투여시 통계적으로 유의하지는 않았으나 treadmill 운동시간을 증가시켰고 glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, lactate dehydrogenase, creatinine, lactate 등의 혈액지표를 개선시켰다. 따라서 홍경천은 과도한 운동 스트레스로 인한 손상을 억제할 수 있는 소재로써의 큰 가능성을 가지고 있는 것으로 판단된다.

• The Journal of Korean Physical Therapy
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• 제24권6호
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• pp.414-418
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• 2012

Purpose: Muscle fatigue affects proprioception, and it causes problems in spinal stability. The purpose of this study was to examine the effect on the accuracy of reproducing the lumbar angles before lumbar exercise and after fatiguing isokinetic lumbar exercise. Methods: Thirty healthy adults participated in this study. Before induction of fatigue by exercise, the proprioception was measured by Biodex. Lumbar positions were passively maintained on stimulation position ($25^{\circ}$ flexion and $25^{\circ}$ extension), and back to the starting position. Subjects actively repositioned the remembered stimulation position, and error degrees between the stimulation position and reposition were measured. Using an isokinetic device at $120^{\circ}$/sec of velocity of angle lumbar flexion/extension exercise resulted in muscle fatigue. The post-fatigue proprioceptive position sense was used in the same way as in pre-fatigue measurement. Results: Means of position sense of pre-fatigue were $2.19{\pm}1.97$ on flexion angle, and $5.04{\pm}2.84$ on extension angle. After exercise induced fatigue, means of position sense were $2.37{\pm}1.83$ on flexion angle, and $4.93{\pm}2.57$ on extension angle. Results of this study showed significant differences of lumbar proprioceptive position sense between pre- and post-fatigue. Conclusion: Lumbar proprioception sense in active repositioning in flexion and extension was affected in the presence of muscle fatigue. Therefore, it should be noted that therapeutic exercise for patients with abnormal proprioceptive sense or elderly people must be performed with care because muscle fatigue can cause secondary damage.

• 한국전문물리치료학회지
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• 제20권2호
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• pp.11-19
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• 2013

Delayed onset muscle soreness (DOMS) is a painful condition that arises from exercise-induced muscle damage after unaccustomed physical activities. Various therapeutic interventions have been applied to reduce the intensity and duration of DOMS-related symptoms. Recently, pulsed electromagnetic field (PEMF) intervention has been introduced as an alternative noninvasive treatment for DOMS. This randomized, double-blind, placebo-controlled experiment was conducted to examine the effects of PEMF therapy on DOMS in elbow flexors at 24, 48, and 72 hours after the experimental DOMS induction. Thirty healthy volunteers ($23{\pm}2.4$ yrs, $175{\pm}5.7$ cm, and $74{\pm}7.8$ kg) participated in this study. Each was randomly assigned to a PEMF or placebo group. On the first day, DOMS was induced in the elbow flexors by repeated isokinetic motions at low ($60^{\circ}/s$) and fast ($120^{\circ}/s$) speeds in all subjects. Thereafter, the PEMF group received 15-min daily treatment with a PEMF device. The placebo group received sham treatment of the same duration. Overall, PEMF application was more effective than the sham treatment in reducing the physiological symptoms associated with the DOMS including perceived soreness, median frequency, and electromechanical delay of the surface electromyography. In addition, median frequency and isokinetic peak torque of the PEMF group recovered to the pre-DOMS induction level earlier than the placebo group. In conclusion, this study suggests that PEMF can be applied as a new recovery strategy in reducing DOMS symptoms. Further experiments are required to examine the effect of the PEMF treatment on different types of exercise conditions and to determine the optimal treatment dosage and duration in a real clinical setting.

• 운동영양학회지
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• 제23권4호
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• pp.26-31
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• 2019

[Purpose] Numerous epidemiological studies have shown that it is possible to prescribe exercise for neurodegenerative disease, such as Alzheimer's disease and Parkinson's disease. However, despite the availability of diverse scientific knowledge, the effects of exercise in this regard are still unclear. Therefore, this study attempted to investigate a substance, such as black chokeberry (Aronia melanocapa L.) that could improve the ability of the treatment and enhance the benefits of exercising in neurodegenerative diseases. [Methods] The cell viability was tested with 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolim-5-carboxanilide and the cells were stained with ethidium homodimer-1 solution. The mRNA expression levels were evaluated by microarray. The active compounds of black chokeberry ethanolic extract (BCE) were analyzed by gas chromatography. The chemical shift analysis in the brain was performed using magnetic resonance spectroscopy. [Results] BCE treatment decreased hydrogen peroxide-induced L6 cell death and beta amyloid induced primary neuronal cell death. Furthermore, BCE treatment significantly reduced the mRNA levels of the inflammatory factors, such as IL-1α, Cxcl13, IL36rn, Itgb2, Epha2, Slamf8, Itgb6, Kdm6b, Acvr1, Cd6, Adora3, Cd27, Gata3, Tnfrsf25, Cd40lg, Clec10a, and Slc11a1, in the primary neuronal cells. Next, we identified 16 active compounds from BCE, including D-mannitol. In vivo, BCE (administered orally at a dosage of 50 mg/kg) significantly regulated chemical shift in the brain. [Conclusion] Our findings suggest that BCE can serve as a candidate for neurodegenerative disease therapy owing to its cyto-protective and anti-inflammatory effects. Therefore, BCE treatment is expected to prevent damage to the muscles and neurons of the athletes who continue high intensity exercise. In future studies, it would be necessary to elucidate the effects of combined BCE intake and exercise.

• 대한물리치료과학회지
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• 제27권3호
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• pp.45-55
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• 2020

Background: The purpose of this study was to investigate the effects of WBC (whole-body cryotherapy)on the MVIC (maximal voluntary isometric contraction)and active ROM (range of motion) recovery of after EIMD (exercise-induced muscle injury). Design: Randomized Controlled Trial. Methods: Thirty subjects who are student in their 20s at a university participated in this study, these subjects were assigned into three groups, a control group (n=10), experiment group I(n=10), and experiment group II (n=10). The subjects in the experimental group II were intervened by WBC (-130℃, 3 minutes) before induced EIMD, the experimental group were intervened by WBC (-130℃, 3 minutes) after induced EIMD, and the control group weren't by any intervened after induced EIMD. Results: First, In the comparison of the MVIC, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the MVIC of experimental group II was significantly larger than those of other groups (p<.001). Second, In the comparison of the active extension angle, there were significant variations with the lapse the time in three groups (p<.001) and there was a significant interaction of time and group (p<.001). In the among group comparison, the active extension angle of experimental group II was significantly smaller than those of other groups (p<.001). Third, In the comparison of the active flexion angle, there were significant variations with the lapse the time in three groups (p<.01) and there was a significant interaction of time and group (p<.001). In the among group comparison, the active flexion angle of experimental group II was significantly larger than those of other groups (p<.05). Conclusion: The above results revealed that the WBC intervention after an exercise had a positive effect of muscle function after EIMD. Therefore we can consider the WBC as a considerable intervention method to prevent or reduce an exercise injury.