ABSTRACT
Delayed-onset muscular soreness (DOMS), the sensation of pain and stiffness in the muscles that occurs from 1 to 5 days following unaccustomed exercise, can adversely affect muscular performance, both from voluntary reduction of effort and from inherent loss of capacity of the muscles to produce force. This reduction in performance is temporary; permanent impairment does not occur. A number of clinical correlates are associated with DOMS, including elevations in plasma enzymes, myoglobinemia, and abnormal muscle histology and ultrastructure; exertional rhabdomyolysis appears to be the extreme form of DOMS.
Presently, the best treatment for DOMS appears to be muscular activity, although the sensation again returns following the exercise. Training for the specific contractile activity that causes DOMS reduces the soreness response. The etiology and cellular mechanisms of DOMS are NOT KNOWN, but a number of hypotheses exist to explain the phenomenon.
The following model may be proposed:
1) high tensions (particularly those associated with eccentric exercise) in the contractile/elastic system of the muscle result in structural damage;
Triadopathies: An Emerging Class of Skeletal Muscle Diseases
The triad is an essential skeletal muscle substructure... The primary role of the triad is to coordinate excitation–contraction coupling (EC coupling). EC coupling is the process by which neuronal input to skeletal muscle [through the release of acetylcholine (ACh) at the NMJ] is transduced into muscle contraction
James J. Dowling, Michael W. Lawlor, and Robert T. Dirksen
2) cell membrane damage leads to disruption of Ca++ homeostasis in the injured fibers, resulting in necrosis that peaks about 2 dayS post-exercise; and
Dominant Mutation of CCDC78 in a Unique Congenital Myopathy with Prominent Internal Nuclei and Atypical Cores
Although the pathogenic mechanism(s) responsible for the presence of excessive central nuclei are still unknown, recent studies have identified abnormal excitation-contraction coupling and impaired calcium homeostasis as common aspects of the disease pathogenesis. Current research is focused on determining how mutations in these gene products resulted in the observed alterations in muscle structure and function, and much remains to be understood about this untreatable and clinically important myopathy subtype.
Karen Majczenko,1,7 Ann E. Davidson,2,7 Sandra Camelo-Piragua,3 Pankaj B. Agrawal,4 Richard A. Manfready,4Xingli Li,2 Sucheta Joshi,2 Jishu Xu,5 Weiping Peng,5 Alan H. Beggs,4 Jun Z. Li,5 Margit Burmeister,1,5,∗ andJames J. Dowling2,6,∗∗
3) products of macrophages activity and intracellular contents accumulate in the interstitium, which in turn stimulate free nerve endings of group-IV sensory neurons in the muscles leading to the sensation of DOMS.
Macrophages
In contrast, the M2 "repair" designation (also referred to as alternatively activated macrophages) broadly refers to macrophages that function in constructive processes like wound healing and tissue repair, and those that turn off damaging immune system activation by producing anti-inflammatory cytokines like IL-10 - Wikipedia
Group III and IV receptors of skeletal muscle. The single largest group of sensoryfibres leaving skeletal muscles are small myelinated or unmyelinated (groups III and IV) fibres. ... Group IV receptors also include high threshold mechanoreceptors and nociceptors.
Group III and IV receptors of skeletal muscle
The evidence so far available suggests that receptors with group III and IV axons play a particular role in nociception and also subserve a wide range of sensory modalities.
Despite their role in nociception, the primary afferent fibres from these receptors do not project to the substantia gelatinosa.
Group IV receptors also include high threshold mechanoreceptors and nociceptors. It is well known that encapsulated receptors are quite unevenly distributed within skeletal muscles and in different skeletal muscles.
Preliminary evidence suggests that the variation in receptor content is not confined to encapsulated receptors, but that the receptors served by group III and IV afferents may have receptive properties that vary from muscle to muscle.
Nociception (also nocioception or nociperception, from Latin nocere 'to harm or hurt') is the sensory nervous system's response to certain harmful or potentially harmful stimuli. - Wikipedia
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Substantia gelatinosa is a collection of cells in the gray area (dorsal horns) of the spinal cord. Found at all levels of the cord, it receives direct input from the dorsal (sensory) nerve roots, especially those fibers from pain and thermoreceptors.
A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. Normally there are four main types in glabrous, or hairless, mammalian skin: lamellar corpuscles, tactile corpuscles, Merkel nerve endings, and bulbous corpuscles.
A nociceptor is a sensory neuron that responds to damaging or potentially damaging stimuli by sending “possible threat” signals to the spinal cord and the brain.
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Plasma Enzymes:
Myoglobinemia:
Myoglobinemia is a condition that is usually caused by acute injury to muscle tissue [1]. It may follow either traumatic or nontraumatic muscle damage that causes the heme pigment, myoglobin, to be released into the blood stream
Abnormal Muscle Histology:
the study of the microscopic structure of tissues.
Abnormal Muscle Ultrastructure:
fine structure, especially within a cell, that can be seen only with the high magnification obtainable with an electron microscope.
Exertional rhabdomyolysis:
Exertional rhabdomyolysis (ER) is the breakdown of muscle from extreme physical exertion. It is one of many types of rhabdomyolysis that can occur, and because of this the exact prevalence and incidence are unclear.
Rhabdomyolysis:
Rhabdomyolysis is a serious syndrome due to a direct or indirect muscle injury. It results from the death of muscle fibers and release of their contents into the bloodstream. This can lead to serious complications such as renal (kidney) failure. This means the kidneys cannot remove waste and concentrated urine.
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Delayed Onset Muscle Soreness occurs from the actions of eccentric contraction.
Eccentric Contraction:
is the motion of an active muscle while it is lengthening under load. Eccentric training is repetitively doing eccentric muscle contractions. (Wikipedia)
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Acute inflammation: the underlying mechanism in delayed onset muscle soreness?
It is well documented in animal and human research that unaccustomed eccentric muscle action of sufficient intensity and/or duration causes disruption of connective and/or contractile tissue. In humans, this appears to be associated with the sensation of delayed onset muscle soreness (DOMS). During the late 1970's, it was proposed that this sensation of soreness might be associated with the acute inflammatory response. However, subsequent research failed to substantiate this theory. The present article suggests that the results of much of the research concerning DOMS reflect events typically seen in acute inflammation. Similarities between the two events include: the cardinal symptoms of pain, swelling, and loss of function; evidence of cellular infiltrates, especially the macrophage; biochemical markers such as increased lysosomal activity and increased circulating levels of some of the acute phase proteins; and histological changes during the initial 72 hours. In the final section of this paper, a theoretical sequence of events is proposed, based on research involving acute inflammation and DOMS.
Delayed Onset Muscle Soreness
Delayed onset muscle soreness (DOMS) is a familiar experience for the elite or novice athlete. Symptoms can range from muscle tenderness to severe debilitating pain. The mechanisms, treatment strategies, and impact on athletic performance remain uncertain, despite the high incidence of DOMS.
DOMS is most prevalent at the beginning of the sporting season when athletes are returning to training following a period of reduced activity. DOMS is also common when athletes are first introduced to certain types of activities regardless of the time of year. Eccentric activities induce micro-injury at a greater frequency and severity than other types of muscle actions.
The intensity and duration of exercise are also important factors in DOMS onset. Up to six hypothesised theories have been proposed for the mechanism of DOMS, namely: lactic acid, muscle spasm, connective tissue damage, muscle damage, inflammation and the enzyme efflux theories. However, an integration of two or more theories is likely to explain muscle soreness. DOMS can affect athletic performance by causing a reduction in joint range of motion, shock attenuation and peak torque. Alterations in muscle sequencing and recruitment patterns may also occur, causing unaccustomed stress to be placed on muscle ligaments and tendons. These compensatory mechanisms may increase the risk of further injury if a premature return to sport is attempted.
Lactic acid is an alpha-hydroxy acid (AHA) due to the presence of carboxyl group adjacent to the hydroxyl group. It is used as a synthetic intermediate in many organic synthesis industries and in various biochemical industries. The conjugate base of lactic acid is called lactate. - Wikipedia
A muscle spasm is a sudden, involuntary contraction of one or more muscles. A spasm results from an abnormally sustained muscle contraction and is often painful. Various muscles may develop spasms, including the small intrinsic hand muscles of a musician to the larger “charley horse” calf muscles of a runner. -
https://www.spine.org/KnowYourBack/Conditions/Other/Muscle-Spasms
These can affect blood flow to the organs and other body tissues. Vasculitis can involve any of the blood vessels. Mixed connective tissue disease. People with MCTD have some features characteristic of several diseases, including lupus, scleroderma, polymyositis or dermatomyositis, and rheumatoid arthritis. -
https://www.webmd.com/a-to-z-guides/connective-tissue-disease
Muscle Damage: A strain to the muscle or muscle tendon is the equivalent of a sprain to ligaments. It is a contraction-induced injury in which muscle fibers tear due to extensive mechanical stress.
https://www.physio-pedia.com/Muscle_Injuries
Inflammation: a localized physical condition in which part of the body becomes reddened, swollen, hot, and often painful, especially as a reaction to injury or infection. - Google Dictionary
The Enzyme Efflux theory: In this theory the micro tears cause a slowed cellular respiration rate which cause the calcium that is in the muscle tissue gets trapped in the cells. The excess calcium triggers proteases and phospholipids to break down and degenerate muscle protein. This causes irritation and inflammation which results in the feeling of soreness. http://personallytrainedbysophie.com/2013/05/muscle-soreness-what-you-need-to-know/
A protease (also called a peptidase or proteinase) is an enzyme that helps proteolysis: protein catabolism by hydrolysis of peptide bonds. Proteases have evolved multiple times, and different classes ofprotease can perform the same reaction by completely different catalytic mechanisms.
Phospholipid: a lipid containing a phosphate group in its molecule, e.g., lecithin. - Google Dictionary
A number of treatment strategies have been introduced to help alleviate the severity of DOMS and to restore the maximal function of the muscles as rapidly as possible.
Nonsteroidal anti-inflammatory drugs have demonstrated dosage-dependent effects that may also be influenced by the time of administration.
Similarly, massage has shown varying results that may be attributed to the time of massage application and the type of massage technique used.
Cryotherapy, stretching, homeopathy, ultrasound and electrical current modalities have demonstrated no effect on the alleviation of muscle soreness or other DOMS symptoms.
Exercise is the most effective means of alleviating pain during DOMS, however the analgesic effect is also temporary.
Athletes who must train on a daily basis should be encouraged to reduce the intensity and duration of exercise for 1–2 days following intense DOMS-inducing exercise. Alternatively, exercises targeting less affected body parts should be encouraged in order to allow the most affected muscle groups to recover. Eccentric exercises or novel activities should be introduced progressively over a period of 1 or 2 weeks at the beginning of, or during, the sporting season in order to reduce the level of physical impairment and/or training disruption. There are still many unanswered questions relating to DOMS, and many potential areas for future research.
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