Relationship between Attenuation of Impact Shock at High Frequency and Flexion-Extension of the Lower Extremity Joints during Downhill Running

류지선,윤석훈,박상균 한국운동역학회 2016 한국운동역학회지 Vol.26 No.2

Objective: The purpose of this study was to determine the interrelationship between ranges of motion of the knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at high frequency (9~20 Hz) in the support phase during downhill running. Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for this study (age, 25.07 ± 5.35 years; height, 175.4 ± 4.6 cm; mass, 75.8 ± .70 kg). Two uniaxial accelerometers were mounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participants were asked to run at their preferred running speed on a treadmill set at 0°, 7°, and 15° downhill. Six optical cameras were placed around the treadmill to capture the coordinates of the joints of the lower extremities. The power spectrum densities of the two acceleration signals were analyzed and used in the transfer function describing the gain and attenuation of impact shock between the tibia and the sacrum. Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. The Pearson correlation coefficient was used to test the relationship between two variables, the magnitude of impact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05. Results: Close correlations were observed between the knee joint range of motion and the attenuation magnitude of impact shock regardless of running slopes (p<.05), and positive correlations were found between the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shock in 15° downhill running (p<.05). Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock during downhill and level running through change in stride or cadence while maintaining stability, and strong and flexible ankle joints are also needed in steeper downhill running. Objective: The purpose of this study was to determine the interrelationship between ranges of motion of the knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at high frequency (9~20 Hz) in the support phase during downhill running. Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for this study (age, 25.07 ± 5.35 years; height, 175.4 ± 4.6 cm; mass, 75.8 ± .70 kg). Two uniaxial accelerometers were mounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participants were asked to run at their preferred running speed on a treadmill set at 0°, 7°, and 15° downhill. Six optical cameras were placed around the treadmill to capture the coordinates of the joints of the lower extremities. The power spectrum densities of the two acceleration signals were analyzed and used in the transfer function describing the gain and attenuation of impact shock between the tibia and the sacrum. Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. The Pearson correlation coefficient was used to test the relationship between two variables, the magnitude of impact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05. Results: Close correlations were observed between the knee joint range of motion and the attenuation magnitude of impact shock regardless of running slopes (p<.05), and positive correlations were found between the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shock in 15° downhill running (p<.05). Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock during downhill and level running through change in stride or cadence while maintaining stability, and strong and flexible ankle joints are also needed in steeper downhill running.

고려 홍삼 투여가 지속적 내리막 달리기 후 CK, GOT, peak torque 및 ROM에 미치는 영향

김형돈 ( Hyung Don Kim ),노호성 ( Ho Sung Nho ),길재호 ( Jae Ho Khil ) 한국스포츠정책과학원(구 한국스포츠개발원) 2004 체육과학연구 Vol.15 No.2

스프린트나 지속적 하향달리기와 같은 고강도의 신장성 운동은 골격근에서 발견되는 혈장 효소의 상당한 변화를 초래하며 또한 근 통증의 발달과 근력의 저하를 가져오는 것으로 알려져 있다. 신장성 운동에 의한 근 손상을 최소화하기 위하여 여러 형태의 처치들이 처방되고 있으며, 본 연구에서는 고려 홍삼이 고강도의 downhill 달리기 후 회복과정에서 미칠 수 있는 근 손상에 대한 보호효과를 확인하는 것이 목적이다. 24명의 대상자들은 이중 맹검법에 의해 무선으로 실험집단(n=12) 또는 위약집단(n=12)으로 나뉘어졌다. 각각의 집단은 고려 홍삼 추출분말 또는 위약(옥수수전분) 캡슐(50mg kg-1 day-1)을 3주간 복용하였으며, 2 주 복용 후 -10% 경사도의 트레드밀에서 70% VO2max의 강도로 45분간 지속적인 달리기를 실시하였다. CK, GOT, ROM과 등척성 및 등속성 피크토크는 downhill 달리기 전, 1일, 2일, 1주일 후에 측정하였다. Downhill 달리기 1주일 전에 downhill 달리기의 운동 강도를 설정하기 위하여 VO2max 검사를 실시하였다. 시기에 따른 집단간의 차이는 repeated measure two way ANCOVA를 통하여, 집단 내 시기에 따른 변화는 one way repeated measure ANOVA를 통하여 분석하였으며 유의수준은 0.05로 설정하였다. 실험집단의 plasma CK, 등척성 피크 토크 와 ROM은 위약집단에 비해 회복기간 중 유의하게 회복되었으며(p<.05) 또한 유의한 (p<.05)상호작용 효과가 발견되었다. 또한, 실험집단은 달리기 후 CK에서 유의하게 증가하였으며. 등척성 피크 토크 및 ROM은 유의하게 감소하였으나 1주일 후에는 downhill 달리기 이전의 정상 상태로 회복하였다. 위약집단 역시 downhill 달리기 후 유의하게 감소하였으나 회복 상태는 상대적으로 지연되었다. 이 같은 결과로 미루어볼 때 고려 홍삼은 근 손상 후 회복과정에서 보호적인 효과를 발휘하였으며, 근 손상 회복을 위한 효과적인 처치 방법 중의 하나가 될 수 있는 것으로 믿어진다. Strenuous eccentric exercise such as downhill running induces remarkable changes of plasma enzyme found in skeletal muscle, and also causes the development of soreness and the loss in muscle strength. The Korean red ginseng was investigated to determine its protective effects during the recovery period after strenuous downhill running. Twenty four male college students participated in the double-blind, placebo-controlled study. The subjects were randomly assigned to either an experimental group (n=12) or placebo group (n=12). Each group received either crude extract powder of Korean red ginseng or placebo (corn starch) for 14 days before and 7 days after a -10% downhill 45-min treadmill run at 70% VO2max (50mg kg-1 day-1). CK, GOT, ROM and maximal isometric and isokinetic force were measured before and 1, 2, 7 days after downhill running. VO2max was also determined on the treadmill 7 days before downhill running for calculation of relative intensity of downhill running. Body composition was measured by electrical impedance method. Differences of groups were analysed using repeated measure two way ANCOVA. One way repeated measure ANOVA was also used to determine difference within each group. Alpha level was set at 0.05. Plasma CK, isometric peak torque, and ROM of experimental group significantly changed during the period of rehabilitation after downhill running (p<.05). Significant differences were also observed over time between groups (p<.05) in CK, isometric peak torque, and ROM. The experimental group dropped in maximal isometric force and ROM from pre-exercise value after downhill running and then significantly regain a strength and ROM (p<.05). It is concluded that Korean red ginseng is very effective to reduce muscle damages and improve recovery rate during the course of rehabilitation.

Relationship between Attenuation of Impact Shock at High Frequency and Flexion-Extension of the Lower Extremity Joints during Downhill Running

Ryu, Ji-Seon,Yoon, Suk-Hoon,Park, Sang-Kyoon Korean Society of Sport Biomechanics 2016 한국운동역학회지 Vol.26 No.2

Objective: The purpose of this study was to determine the interrelationship between ranges of motion of the knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at high frequency (9~20 Hz) in the support phase during downhill running. Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for this study (age, $25.07{\pm}5.35years$; height, $175.4{\pm}4.6cm$; mass, $75.8{\pm}.70kg$). Two uniaxial accelerometers were mounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participants were asked to run at their preferred running speed on a treadmill set at $0^{\circ}$, $7^{\circ}$, and $15^{\circ}$ downhill. Six optical cameras were placed around the treadmill to capture the coordinates of the joints of the lower extremities. The power spectrum densities of the two acceleration signals were analyzed and used in the transfer function describing the gain and attenuation of impact shock between the tibia and the sacrum. Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. The Pearson correlation coefficient was used to test the relationship between two variables, the magnitude of impact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05. Results: Close correlations were observed between the knee joint range of motion and the attenuation magnitude of impact shock regardless of running slopes (p<.05), and positive correlations were found between the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shock in $15^{\circ}$ downhill running (p<.05). Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock during downhill and level running through change in stride or cadence while maintaining stability, and strong and flexible ankle joints are also needed in steeper downhill running.

Relationship between Attenuation of Impact Shock at High Frequency and Flexion-Extension of the Lower Extremity Joints during Downhill Running

( Ji Seon Ryu ),( Suk Hoon Yoon ),( Sang Kyoon Park ) 한국운동역학회 2016 한국운동역학회지 Vol.26 No.2

Objective: The purpose of this study was to determine the interrelationship between ranges of motion ofthe knee and ankle joints on the sagittal plane and the attenuation magnitude of impact shock at highfrequency (9~20 Hz) in the support phase during downhill running.Method: Fifteen male heel-toe runners with no history of lower extremity injuries were recruited for thisstudy (age, 25.07 ± 5.35 years; height, 175.4 ± 4.6 cm; mass, 75.8 ± .70 kg). Two uniaxial accelerometers weremounted to the tuberosity of tibia and sacrum, respectively, to measure acceleration signals. The participantswere asked to run at their preferred running speed on a treadmill set at 0°, 7°, and 15° downhill. Sixoptical cameras were placed around the treadmill to capture the coordinates of the joints of the lowerextremities. The power spectrum densities of the two acceleration signals were analyzed and used in thetransfer function describing the gain and attenuation of impact shock between the tibia and the sacrum.Angles of the knee and ankle joints on the sagittal plane and their angle ranges were calculated. ThePearson correlation coefficient was used to test the relationship between two variables, the magnitude ofimpact shock, and the range of joint angle under three downhill conditions. The alpha level was set at .05.Results: Close correlations were observed between the knee joint range of motion and the attenuationmagnitude of impact shock regardless of running slopes (p<.05), and positive correlations were foundbetween the ranges of motion of the knee and ankle joints and the attenuation magnitude of impact shockin 15° downhill running (p<.05).Conclusion: In conclusion, increased knee flexion might be required to attenuate impact shock duringdownhill and level running through change in stride or cadence while maintaining stability, and strongand flexible ankle joints are also needed in steeper downhill running.

운동 형태가 다른 달리기 시 혈중 항염증 사이토카인 변화

신영오(Young-Oh Shin),김정규(Jung-Kyu Kim),이정범(Jeong-Beom Lee) 한국생활환경학회 2009 한국생활환경학회지 Vol.16 No.3

The purpose of this study was to investigate the alteration of plasma anti-inflammatory cytokines, including interleukin-6 (IL-6), soluble TNF receptor (sTNFr), IL-10, and interleukin-1 receptor antagonist (IL-1ra), during different types of running exercise(level and downhill running). Seven healthy male college students completed two different exercise trials on separate occasions: (1) level treadmill running at 75% VO₂max for 30 min; (2) downhill treadmill running (?12% gradient) at 75% VO₂max for 30 min. Blood was sampled before, immediately after, and 1 h, 4 h, 24 h after exercise. Visual analog scale (VAS) score was obtained at the same time point. Plasma was analyzed for cytokines and creatine kinase (CK) activity. The plasma concentrations of IL-6 increased significantly (P<0.05) after exercise in both trials but there was a difference in pattern of change between trials. CK activity and VAS score increased significantly after the downhill running but not in level running trial. IL-10, as like IL-6, increased significantly (P<0.05 or P<0.01) after downhill running but not in level running. There was no significant alteration of sTNFr and IL-1ra in both running trials. In conclusion, there was a different pattern in response of exercise-induced anti-inflammatory cytokines such as IL-6 and IL-10 between running types (level and downhill).

Effects of Downhill Running Exercise on Glucose Tolerance and Skeletal Muscle P-AMPK Expression in Type II Diabetes Rats

박성태 대한운동학회 2022 아시아 운동학 학술지 Vol.24 No.2

OBJECTIVES The purpose of this study was to investigate the effects of moderate downhill running exercise on glucose tolerance and skeletal muscle phospho-AMP activated protein kinase(P-AMPK) expression in type Ⅱ diabetes rats. METHODS 8-week-old, 24 wistar & GK rats (type Ⅱ diabetes model) were randomly divided into 4 groups, NR, NE, DR, DE. Downhill running treatment were performed on the treadmill at the -16 % and speed of 16m/min for 1 hour. All groups were done with Oral glucose tolerance test(OGTT) and after 1 week washout period, rats in exercise groups performed downhill running. After exercise treatment, soleus muscle of rats were extracted for test of P-AMPK expression. RESULTS In OGTT, blood glucose levels in all groups were increased after the oral glucose load and these were significantly differ from rest level. But in DE group, blood glucose level at 120 min after OGTT was not significantly differ from rest level. In immunoblotting test for P-AMPK expression of skeletal muscle, NE group was significantly higher than NR group and DE group was significantly higher than other groups. CONCLUSIONS Downhill running exercise improved glucose tolerance and increased P-AMPK expression of skeletal muscle in type Ⅱ diabetes rats.

운동생리학 : 덱사메타손 투여가 신장성 운동에 의한 근 부상 후 회복에 미치는 영향

허만동(HeoManDong) 한국체육학회 2004 한국체육학회지 Vol.43 No.2

The purpose of this study was to investigate the effects of dexamethasone supplementations on chemical markers of muscle damages, which occurs during downhill treadmill running(16% decline, 30m/min, 1h), in 16 Sprague-Dawley rats. The rats were randomly divided into two groups. They were control group(CON) and dexamethasone adminstration group(DEX). The dexamethasone dminstration group had 0.1mg/kg/day after downhill running. The chemical markers examined in this study included metabolic enzymes such as creatine phosphokinase(CPK) and lactate dehydrogenase(LDH) and hormones(testosterone and cortisol) in circulating plasma. In addition, plasma concentrations of glucose, insulin, leptin and lipids were also measured along with muscle mass, retroperitoneal fat mass, running time to exhaustion. Two-way ANOVA followed by LSD post hoc tests were used to test possible group by treatment interactions, and the results were as follows:1) With respect to plasma CPK activity, there were no significant group(p>.05) and significant time main effects(p< .05), with no significant group by time interaction; the DEX group had significantly lower CPK activity than the control group at the 48-hr postexerise period.2) With respect to plasma LDH activity, there was a no significant group and time(p >.05), with significant group by time interaction(p< .05).3) There were a no significant group by time interaction for testosterone and cortisol concentrations(p >.05).4) There were significant group differences in growth body weight percent changes(p<.05).5) There were significantly higher values to the ratio of soleus muscle to body weight, than the CON(p< .05).6) There were no significantly to the ratio of gastrocnemius muscle to body weight(p >.05).7) There were significantly lower values to the ratio of retroperitoneal fat to body weight, than the CON(p<.05).

운동생리학 : 평지와 내리막 달리기 운동에 따른 혈중 암모니아와 젖산 농도 변화가 운동 후 CK 활성 및 호르몬 변화에 미치는 영향

김정규(JungKyuKim),문희원(HeeWonMoon) 한국체육학회 2004 한국체육학회지 Vol.43 No.4

The purpose of this study was to examine the effects of serum ammonia and lactate accumulation following level and downhill running on creatine kinase activities and the ratio of cortisol and testosterone secretion. The running tests were performed on a treadmill for 30 min and all subjects(n=10) of present study participated in two different kinds of experimental conditions.: one was level running(LR) and the others was downhill running(DR) at a decline angle -14 % with their favorable running speed.There were significant difference in the total VO2 between LR and DR conditions(p<.05). In the mean blood lactate concentration at the end of the 30 min running exercise, there were significant differences between LR and DR conditions(p<.05). In the mean blood ammonia concentration at the end of 30 min running exercise, there were significant differences between LR and DR conditions(p<.05). The mean blood CK activity of DR was higher than that of LR group at the 12 h, 24 h, and 48 h post exercise, and there were significant difference between LR and DR conditions(p<.05). In the mean blood testosterone concentration, there were no significant difference between LR and DR conditions(p>.05). In the mean blood cortisol concentration and the testosterone/cortisol ratio, there were significant difference between LR and DR conditions at 12 h post exercise(p<.05). In the downhill running, CK activity in the blood as an indicator of muscle damage was a significantly higher at the 12-24 h post exercise, one of most effective blood fatigue factor on delayed muscle damage might be ammonia concentration and production during eccentric exercise. Thus, downhill running had a potential possibility of muscle damage and cortisol might played important role in the metabolic compensation for muscle damage

내리막 달리기 후 국소 근손상의 영상학적 비교분석 : 운동 강도의 영향

선민규,김춘섭,김맹규 한국응용과학기술학회 2019 한국응용과학기술학회지 Vol.36 No.3

본 연구는 내리막 달리기(downhill running, DR) 후 초음파 영상분석을 이용해 대퇴사두근 무리 (quadriceps group, QG) 내 근손상의 국소화 여부를 검증하고, DR 동안 운동 강도가 운동유발성 근손상 (exercise-induced muscle damage, EIMD) 및 근육 반향세기 변화에 미치는 영향을 규명하려는 목적으로 수행되었다. 규칙적인 신체활동이 없는 건강한 남성 11명이 무작위 교차설계에 따라 서로 다른 강도 [low-intensity DR session(50%HR max ), LDR; high-intensity DR session(70%HR max ), HDR]의 DR 운동을 수행하였다. DR 후 EIMD의 심각성은 혈청크레아틴 키나아제(creatine kinase, CK) 활성 수준 변화와 함께 신경근 기능 지수로서 무릎 신전근의 최대 수의적 등척성 수축(maximal voluntary isometric contraction, MVIC) 및 관절가동범위(range of motion, ROM) 변화를 통해 결정되었다. 회색조 분석을 적용한 근육 반향세기 평가는 DR에 따른 QG 내 국소 근육별(rectus femoris, RF; vastus lateralis, VL; vastus medialis, VM; vastus intermedius, VI) 손상 양상을 탐지하기 위해 활용되었다. 모든 세션에서 혈청 CK 활성 수준과 VL 및 VM의 근통증 정도는 운동 후 24시간째(RF의 경우 각각 LDR 24시간째와 HDR 48시간째) 최대에 이르렀 으며, 혈청 CK 수준에서 운동 강도에 따른 유의한 차이(p<.05)가 나타난 반면 근통증에서 세션 간 통계적 차이는 없었다. 무릎 관절을 이용한 MVIC 및 ROM과 같은 신경근 기능 지표 및 VM을 제외한 모든 QG 근육 반향세기는 운동 직후 극적으로 감소 또는 증가 후 72시간까지 점진적 회복 양상을 나타내었다. 그러나 신경근 기능 지표에서 운동 강도에 따른 통계적 차이는 없었으나 RF 및 VL 반향세기에서 세션 내 및 세션간 유의한 차이(p<.01)를 나타내었다. 본 연구의 결과로 ECC를 함유한 DR 운동 시 운동 강도는 DOMS 및 신경근 기능 지표에 부분적으로 영향을 미칠 가능성이 있으며, 특히 혈청 CK 수준과 함께 RF 및 VL의 근육 반향세기는 운동 강도의 영향을 직접적으로 반영한다는 사실을 알 수 있다. 또한, 현재 연구결과는 DR 동안 ECC를 겪는 QG 내 국소 근육 간 근손상 정도가 다를 수 있으며 초음파 근육 반향세기가 국소 근육의 EIMD 심각성을 차별화할 수 있는 유용한 평가기법임을 뒷받침하고 있다. The current study was performed to investigate the magnitude of exercise-induced muscle damage (EIMD) after downhill running (DR) of different intensities and to examine the availability of muscle echo intensity as biomarkers to detect regional damage within quadriceps muscle group (QG) following DR. Healthy college-age men (n=11) were experienced twice DR sessions [50%HR max DR, LDR; 70%HR max DR, HDR] separated by a 2-week wash-out period with the random order. After DR, severity of EIMD according to exercise intensity were determined by serum creatine kinase (CK) activity, muscle tenderness, and neuromuscular function indicators such as a maximal voluntary isometric contraction (MVIC) and range of motion (ROM). Transvaginal B-mode imaging had been employed to evaluate regional muscle echo intensity within QG [rectus femoris, RF; vastus lateralis, VL; vastus medialis, VM; vastus intermedius, VI]. After both DR sessions, changes in serum CK activity and muscle tenderness have tended to more increase in HDR compared to those of LDR. There was a significant interaction effect between exercise intensity during DR and the time course of serum CK activity(p<.05). However, there were no statistical differences between sessions in muscle tenderness. The time course of changes in the neuromuscular functions after DR were similar to those of regional muscle echo intensity regardless exercise intensity. Although neuromuscular function showed to decline in HDR more than those of LDR after DR, no statistical differences between sessions. In contrast, there were significant interaction effects between sessions and time course of changes in RF and VL muscle echo intensity(p<.01), but not shown in those of VI and VM. These results indicated that each muscles within the QG show different response profiles for EIMD during DR, exercise intensity influences on these responses as well. In particular, current findings suggested that muscle echo intensity derived from ultrasound imaging is capable of detecting regional muscle damage in QG following DR.

Irisin response to downhill running exercise in humans

Yoshifumi Tsuchiya,Sahiro Mizuno,Kazushige Goto 한국운동영양학회 2018 Physical Activity and Nutrition (Phys Act Nutr) Vol.22 No.2

[Purpose] To determine the effects of exercise-induced muscle damage, we examined irisin responses during level running (LR), with less muscle damage, and downhill running (DHR), with greater muscle damage under equivalent exercise duration and oxygen consumption (V3O2) conditions. [Methods] Fifteen healthy men (age: 21.6 ± 2.0 y, height: 170 ± 1.3 cm, weight: 64.8 ± 2.7 kg) were randomly assigned to either the LR group (n = 8) or the DHR group (n = 7). Subjects in the LR group performed treadmill running at 70% of maximum oxygen uptake (V3O2max) for 30 min on a 0% gradient. In contrast, subjects in the DHR group performed the same exercise on a –10% gradient. Blood samples were collected before exercise, immediately after exercise, and 1, 3, and 24 h after exercise. [Results] No significant interaction (group × time) or main effect of group or time was observed for changes in plasma irisin concentrations over time (P > 0.05). However, the area under the curve of plasma irisin concentrations during a 3-h post-exercise period was significantly greater in the DHR (239,197 ± 8,166 ng/mL) group than in the LR (92,293 ± 8,755 ng/ml) group (P < 0.05). The blood lactate, serum cortisol, myoglobin, and plasma interleukin-6 concentrations were significantly higher in the DHR group than in the LR group after exercise (P < 0.05 for all variables). [Conclusion] DHR associated with marked muscle damage promoted a greater increase in exercise-induced irisin did LR after the same duration under identical VO2 conditions.