TIME COURSE OF ATTENUATION OF PROTECTIVE EFFECT AGAINST ECCENTRIC EXERCISE-INDUCED MSUCLE DAMAGE

A single bout of eccentric exercise confers a long-lasting protective effect against subsequent bouts of the same exercise. This study investigated how the protective effect was lessened when the interval between the initial and secondary exercise bouts was increased from 4 to 12 weeks. Thirty young men performed two bouts of 12 maximal eccentric actions of the elbow flexors of the nondominant arm separated by either 4 (n = 9), 8 (n = 10), or 12 (n = 11) weeks. Maximal isometric strength, flexed and relaxed elbow joint angles, range of motion, upper arm circumference, muscle soreness, plasma creatine kinase (CK), and myoglobin (Mb) were measured before, immediately after, and for 4 days after exercise. Changes in criterion measures were compared between bouts for each group and among groups by two-way repeated-measures ANOVA. There were no significant differences among groups in the changes in all measures following the first bout. Significantly (p < 0.05) smaller responses in all measures were observed after the second bout as compared with first bout for the 4 and 8 weeks, but only in strength, muscle soreness, CK, and Mb for the 12 weeks. It was concluded that some aspects of the protective effect were attenuated after 8 weeks, and the factors responsible for the effect vary among the measures. Key words: maximal isometric strength, creatine kinase, myoglobin, range of motion, muscle soreness

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Time course of the protective effect of inhaled heparin on exercise-induced asthma.

American Journal of Respiratory and Critical Care Medicine ◽

10.1164/ajrccm.153.5.8630624 ◽

1996 ◽

Vol 153 (5) ◽

pp. 1702-1707 ◽

Cited By ~ 60

Author(s):

J Garrigo ◽

I Danta ◽

T Ahmed

Keyword(s):

Protective Effect ◽

Time Course ◽

Exercise Induced

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The cytokine response to strenuous exercise

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y98-055 ◽

1998 ◽

Vol 76 (5) ◽

pp. 505-511 ◽

Cited By ~ 135

Author(s):

Bente Klarlund Pedersen ◽

Kenneth Ostrowski ◽

Thomas Rohde ◽

Helle Bruunsgaard

Keyword(s):

Muscle Damage ◽

Eccentric Exercise ◽

Time Course ◽

Close Association ◽

Serum Levels ◽

Strenuous Exercise ◽

Necrosis Factor Alpha ◽

Sequential Release ◽

Systemic Endotoxemia ◽

Exercise Induced

Strenuous exercise is accompanied by an increase in circulating proinflammatory and inflammation responsive cytokines, having some similarities with the response to sepsis and trauma. The sequential release of tumour necrosis factor-alpha, interleukin (IL)1beta, IL-6, and IL-1 receptor antagonist (IL-1ra) in the blood is comparable to that observed in relation to bacterial diseases. Eccentric exercise is associated with an increase in serum IL-6 concentrations and is significantly correlated with the concentration of creatine kinase (CK) in the following days, whereas no changes are found after the concentric exercise; this demonstrates a close association between exercise-induced muscle damage and increased serum levels of IL-6. The time course of cytokine production, the close association with muscle damage, and the finding of mRNA-IL-6 in skeletal muscle biopsies after intense exercise all support the idea that during eccentric exercise myofibers are mechanically damaged and that this process stimulates the local production of inflammatory cytokines. It remains to be shown whether systemic endotoxemia during exercise is also a cause of elevated levels of cytokines in the plasma. The present review also discusses the possible roles of protein breakdown, delayed onset muscle soreness, and clinical implications of the acute-phase response following exercise.Key words: exercise, sport, trauma, sepsis, cytokines, interleukin, muscle.

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Protective effect of vitamin E on exercise-induced oxidative damage in young and older adults

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1993.264.5.r992 ◽

1993 ◽

Vol 264 (5) ◽

pp. R992-R998 ◽

Cited By ~ 16

Author(s):

M. Meydani ◽

W. J. Evans ◽

G. Handelman ◽

L. Biddle ◽

R. A. Fielding ◽

...

Keyword(s):

Vitamin E ◽

Oxidative Damage ◽

Protective Effect ◽

Eccentric Exercise ◽

Conjugated Dienes ◽

Alpha Tocopherol ◽

Double Blind ◽

Tocopherol Concentration ◽

Exercise Induced ◽

Vitamin E Supplementation

The protective effect of vitamin E supplementation on exercise-induced oxidative damage was tested in 21 male volunteers. Nine young (22-29 yr) and 12 older (55-74 yr) sedentary male subjects participated in a double-blind protocol and received either 800 IU dl-alpha-tocopherol or a placebo daily. After 48 days, vitamin E supplementation significantly increased alpha-tocopherol in plasma and skeletal muscle. Subjects then performed a bout of eccentric exercise at 75% of their maximum heart rate by running down an inclined treadmill for 45 min. All vitamin E-supplemented subjects excreted less (P < 0.05) urinary thiobarbituric acid adducts after the exercise bout than placebo subjects at 12 days postexercise (35 and 18% above baseline in young and old supplemented groups, respectively, vs. 60 and 80% in young and old placebo groups, respectively). After exercise, the initial difference in alpha-tocopherol concentration of muscle between young placebo and vitamin E-supplemented groups was diminished and muscle lipid conjugated dienes tended to increase (P = 0.09) in placebo subjects. Placebo subjects had a significant decrease in major fatty acids of muscle biopsy taken immediately after exercise. When normalized for the hemoconcentration effects of exercise, the plasma concentration of vitamins E and C and uric acid showed no significant change. The alterations in fatty acid composition, vitamin E, and lipid conjugated dienes in muscle and in urinary lipid peroxides in controls after eccentric exercise are consistent with the concept that vitamin E provides protection against exercise-induced oxidative injury.

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Protective Effect Conferred by Isometric Preconditioning Against Slow- and Fast-Velocity Eccentric Exercise-Induced Muscle Damage

Frontiers in Physiology ◽

10.3389/fphys.2019.01203 ◽

2019 ◽

Vol 10 ◽

Author(s):

Renan Vieira Barreto ◽

Leonardo Coelho Rabello de Lima ◽

Camila Coelho Greco ◽

Benedito Sérgio Denadai

Keyword(s):

Protective Effect ◽

Muscle Damage ◽

Eccentric Exercise ◽

Exercise Induced

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How long does the protective effect on eccentric exercise-induced muscle damage last?

Medicine & Science in Sports & Exercise ◽

10.1097/00005768-200109000-00011 ◽

2001 ◽

Vol 33 (9) ◽

pp. 1490-1495 ◽

Cited By ~ 152

Author(s):

KAZUNORI NOSAKA ◽

KEI SAKAMOTO ◽

MIKE NEWTON ◽

PAUL SACCO

Keyword(s):

Protective Effect ◽

Muscle Damage ◽

Eccentric Exercise ◽

Exercise Induced

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A semiquantitative scoring tool to evaluate eccentric exercise-induced muscle damage in trained rats

European Journal of Histochemistry ◽

10.4081/ejh.2015.2544 ◽

2015 ◽

Vol 59 (4) ◽

Cited By ~ 4

Author(s):

D. Rizo-Roca ◽

J.G. Ríos-Kristjánsson ◽

C. Núñez-Espinosa ◽

A. Ascensão ◽

J. Magalhães ◽

...

Keyword(s):

Skeletal Muscle ◽

Muscle Damage ◽

Muscle Fibre ◽

Eccentric Exercise ◽

Muscle Injury ◽

Time Course ◽

Intraclass Correlation ◽

Post Injury ◽

Exercise Induced ◽

Scoring Tool

Unaccustomed eccentric exercise is a well-documented cause of exercise-induced muscle damage. However, in trained subjects muscle injury involves only light or moderate tissue damage. Since trained rats are widely used as a model for skeletal muscle injury, here we propose a semiquantitative scoring tool to evaluate muscle damage in trained rats. Twenty male Sprague-Dawley rats were trained fortwo weeks following a two-week preconditioning period, and randomly divided into two groups: control rats (CTL; n=5) and rats with eccentric exercise-induced muscle damage (INJ; n=15). Injured rats were sacrificed at three time points: 1, 3 and 7 days post injury (n=5 each). Transverse sections from the right soleus were cut (10 µm) and stained with haematoxylin-eosin. Samples were evaluated by two groups of observers (four researchers experienced in skeletal muscle histopathology and four inexperienced) using the proposed tool, which consisted of six items organised in three domains: abnormal fibre morphology, necrotic/(re)degenerating fibres (muscle fibre domain), endomysial and perimysial infiltration (inflammatory state domain) and endomysium and perimysium distension (interstitial compartment domain). We observed the expected time course in the six evaluated items. Furthermore, agreement among observers was evaluated by measuring the Intraclass Correlation Coefficient (ICC). Within the experienced group, items from the muscle fibre and interstitial compartment domains showed good agreement and the two items from the infiltration compartment domain showed excellent agreement. in conclusion, the proposed tool allowed quick and correct evaluation of light to moderate muscle damage in trained rats with good agreement between observers.

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