Term
| what is a myotendinous junction |
|
Definition
| interface between ends of skeletal muscle cells and the connective tissue of tendons |
|
|
Term
| is there stress concentration at the myotendinous junction? |
|
Definition
|
|
Term
| is the myotendinous junction a common site of injury |
|
Definition
|
|
Term
| how is the myotendinous junction specialized to reduce injury |
|
Definition
| muscle cell membranes have extensive folds that enable interdigitations with tendon and make astronger interface with connective tissue/tendon. Digit-like processes extedn from the muscle cell toward the tendon tissue to which it adheres. |
|
|
Term
| how do terminal sarcomeres compare to mid-substance sarcomeres |
|
Definition
|
|
Term
| what is the functional unit of the muscle |
|
Definition
|
|
Term
| sarcomere goes from what to what |
|
Definition
|
|
Term
| what filaments attach to the z band |
|
Definition
|
|
Term
| what filiaments are between the actin filaments in the center of the sarcomere |
|
Definition
|
|
Term
| what makes skeletal muscle striated |
|
Definition
| different actin and myosin fibers |
|
|
Term
| which is stiffer/stronger, tendon or muscle? |
|
Definition
|
|
Term
| how does the body minimize stress concentration between tendon and muscle? |
|
Definition
| making the terminal sarcomeres of muscle stronger and stiffer so that you go from unstiff sarcomeres to stiffer sarcomeres to even stiffer tendon |
|
|
Term
| what is the purpose of the finger-like projections of muscle? |
|
Definition
| to give a broader surface area between the muscle and the collagen to give it a stronger bond |
|
|
Term
| what are the 2 mechanical effects of muscle membrane foldin |
|
Definition
| 1. increases contact area for muscle and tendon interface, resulting in greater strength of the interface. 2. decreases the angle of junction loading. |
|
|
Term
| how does the acute approach angle (theta) increase strength of myotendinous juncture |
|
Definition
| gives more contact area between tendon's collagen fibers and muscle cells. |
|
|
Term
| what type of injury does the acute approach angle prevent? |
|
Definition
|
|
Term
| what are the effects of disuse atrophy on muscle-tendon juncture? |
|
Definition
| increased incidence of myotendinous junction failure; increase in angle of joint loading between basement membrane of the muscle cell interdigitations and extracellular connective tissue matrix = loss of finger-like projections of the muscle cells |
|
|
Term
| what are the effects of exercise on myotendinousjunction structure? |
|
Definition
| more finger-like branches in the terminal sarcomeres; improved interface and strength between muscle and tendon in the face of shearing stress |
|
|
Term
| what are the 2 categories of muscle strain injuries |
|
Definition
|
|
Term
| what are direct muscle strain injuries |
|
Definition
| injuries caused by trauma such as laceration or contusion |
|
|
Term
| what are indirect muscle strain injuries |
|
Definition
| injuries caused by stretching, development of active tension in the muscle, or both (eccentric injury) |
|
|
Term
| describe what happens in an eccentric muscle strain injury |
|
Definition
| external environment creates stretching of the muscle tendon unit and while the internal environment is contracting. There is an unusually high level of tensile stress within the muscle tendon unit. |
|
|
Term
| is there more muscle tension with eccentric or concentric contractions? |
|
Definition
|
|
Term
| what is delayed onset muscle soreness |
|
Definition
| muscle soreness that peaks 1-3 days post-exercise |
|
|
Term
| what type of loading is more likely to cause DOMS |
|
Definition
| eccentric loading associated with greater dependence on passive connetive tissue tension in the muscle |
|
|
Term
| what is hydroxyproline, and what does it indicate? |
|
Definition
| hydroxyproline is a marker of connective tissue breakdown that is seen in the blood of people with DOMS |
|
|
Term
| histologically, what is seen in patients with DOMS |
|
Definition
| disruption of sarcomere banding |
|
|
Term
| what does the disruption of sarcomere banding suggest |
|
Definition
| mechanical injury: shearing failure wihtin the muscle between adjacent portions. |
|
|
Term
|
Definition
|
|
Term
| what is the common site of injury in a muscle strain injury |
|
Definition
| near the myotendinous junction but not right at the junction |
|
|
Term
| why is the common site of injury in a muscle strain injury near but not at junctino? |
|
Definition
| terminal sarcomeres are structurually different and mechanically more stiff, reducing stress concentration at the junction. The terminal sarcomere units will remain attached to the interfacing tendon. |
|
|
Term
| what directs the site of injury in muscle strain injury? |
|
Definition
| stress concentration caused by the dissimilar mechanical properties of the 2 sarcomere types: normal and shorter/stiffer ternimal ones |
|
|
Term
| what is the first step of the Jarvinen protocol for myotendinous junction injury? |
|
Definition
| immobilization in a shortened position |
|
|
Term
| when you immobilize a muscle in a shortened position for a reason other than muscle injury, what do you expect the outcome on muscle to be |
|
Definition
| reduced ultimate strength, less length at failure, fails more easily, reduced functional ROM, failure occurs at myotendinous junction |
|
|
Term
| physiologically, what occurs with immobilization in muscle |
|
Definition
| the muscle tissue changes because of a lack of tensile stress in the muscle |
|
|
Term
| histologically, what happens with immobilized muscle |
|
Definition
| fewer sarcomeres. The sarcomeres that are there are slightly longer, but not enough to compensate for fewer sarcomeres. There is less overall length when it is pulled apart to failure. |
|
|
Term
| how is ultimate strength of the muscle affected by immobilization |
|
Definition
| it is decreased. You will prematurely reach the end of extensibility, and the muscle will tear easily because of decreased ultimate strength |
|
|
Term
| why must you be careful with muscle that has been immobilized in a shortened position |
|
Definition
| the muscle will be at risk for failure because you can't stretch it as far and it is structurally weaker with a lower peak on the stress-strain curve |
|
|
Term
| what is the result of immobilization of muscle in a lengthened position? |
|
Definition
| greater ultimate strength and overall length at failure compared with control specimens |
|
|
Term
| what stimulates the number of sarcomeres in a muscle? |
|
Definition
|
|
Term
| when a muscle is immobilized in a lengthened position, how do the sarcomeres change in size and number/ |
|
Definition
| there are more sarcomeres, but they are slightly shorter than normal sarcomeres |
|
|
Term
| how does the muscle tendon tissue change overall when it is immobilized in a lengthened position? |
|
Definition
| the tissue will be increased overall and will be hypertrophied because of the passive tensile stress |
|
|
Term
| how long does it take to change muscle length with immobilization |
|
Definition
|
|
Term
| what is the normal length-tension relationship of muscle? |
|
Definition
| with length on the x axis and tension on the y axis, as length increases, tension increases to a point. After that, as length increases more, tension decreases. |
|
|
Term
| if you immobilize in a shortened position, how does the length-tension relationship change? |
|
Definition
| it takes less length to increase tension. The tissue can undergo less lengthening overall before failure |
|
|
Term
| if you immobilize in a lengthened position, how does the length-tension relationship change |
|
Definition
| the muscle-tendon unit is longer, so there is a greater length that can occur before failure and there is a greater tension that can occur |
|
|
Term
| how does immobilizing in a lengthened position affect strength? |
|
Definition
| the lengthened muscle is very weak in MMT because it has to go to a shortened position for MMT. The sarcomeres are too short and there is competition from opposing bond sites that prevents maximum interaction. The non-contractile tissue is all floppy in crimp. This is stretch weakness. |
|
|
Term
| how does immobilizing in a shortened position affect strength? |
|
Definition
| the shortened muscle appears stronger in MMT position because it is being tested near optimal length. |
|
|
Term
| how does warming up affect the myotendinous junction |
|
Definition
| warming up externally or physiologically results in greater ultimate strenth and greater strain at failure for collagenous tissue |
|
|
Term
| why is it especially important for the weekend warrior to warm up? |
|
Definition
| they have a large approach angle, but warming up can help to decrease chance of injury |
|
|
Term
| how does disuse atrophy place the myotendinous junction at risk for injury |
|
Definition
| disuse causes a larger approach angle of the collagen fibres that approach the muscle cell membrane. |
|
|
Term
| after disuse, how can you reverse the change and make the muscle tendon junciton stronger? |
|
Definition
| a slow, progressive increase in intensity, frequency, duration of laoding. |
|
|
Term
| if the muscle is not injured, what is the best principle for immobilizing and why |
|
Definition
| if immobilization is not because of the muscle, the immobilization should occur with the muscle in as great a length as is possible so you don't get contracture and you don’t' get a decrease in the ultimate strength of the muscle tendon comples. |
|
|
Term
| what is a common theme for myotendinous junction implications for intervention: what is good for all patients? |
|
Definition
| warm-up is good, especially for at-risk muscle tissue |
|
|
Term
| where in the muscle are strains most likely to occur |
|
Definition
|
|
Term
| can muscle strains occur at locations other than the myotendinous junctin? |
|
Definition
|
|
Term
| what other injuries are seen in muscle |
|
Definition
| crush injuries from contusion, lacerations from sharp penetration |
|
|
Term
| what is the regeneration capability of muscle injury? |
|
Definition
| muscle tissue has the capability to regenerate with real muscle tissue, but if you have an injury to muscle, there will be an inflammatory response that will want to produce fibroblastic scar |
|
|
Term
| what is fibroblastic scar tissue like? |
|
Definition
| like tendon tissue: high collagen content |
|
|
Term
| why is it bad to have a lot of fibroblastic scar formation in muscle? |
|
Definition
| scar tissue between soft muscle tissue creates 2 sites of stress concentration: muscle tissue-fibroblastic scar-muscle tissue. Scar tissue is also inelastic and weaker than original muscle tissue, increasing risk of reinjury |
|
|
Term
| what should intervention be focused on following muscle injury |
|
Definition
| minimize bleeding and inflammatory response to minimize scar tissue formation |
|
|
Term
| what would you prefer to have bridge the gap instead of fibroblastic scar tissue? |
|
Definition
|
|
Term
| what cells are responsible for trying to bridge the gap across a muscle strain injury to form new muscle? |
|
Definition
| muscle repair satellite cells |
|
|
Term
| what do muscle repair satellite cells do |
|
Definition
| they lie dormanent until a muscle injury occurs. Then they are the precursors of mybolasts for muscle cell regneration |
|
|
Term
| describe the appearance and location of muscle repair satellite cells |
|
Definition
| they are mononucleated cells and are positioned between the basal lamina and the myofibril cell membrane |
|
|
Term
| how do muscle repair satellite cell quality and quantity change with age? |
|
Definition
| the number of these reparative cells decreases with age, and their metabolic activity decreases with age |
|
|
Term
| are there more muscle repair satellite cells in Type I or Type II muscle fibers? |
|
Definition
| there are more muscle repair satellite cells in Type I slow twitch muscle fibers |
|
|
Term
| is the capability for repair greater in Type I or Type II muscle fibers? |
|
Definition
|
|
Term
| List the sequence of events with muscle strain injury |
|
Definition
| 1. Damaged muscle cells release a mitogenic factor that stimulates muscle repair satellite cell mitosis; 2. Proliferating satellite cells differentiate into myoblasts, fusing to form myotube; 3. Myotube is the precursor of the myofibril muscle cell; 4. Myoblasts actively produce myofibrillar proteins actin and myosin that form the sarcomere contractile units |
|
|
Term
| what is the result of this sequence of events with muscle strain injury |
|
Definition
| the muscle produces real muscle tissue! You don't have to be left with the scar! |
|
|
Term
| List the sequence of events of myogenesis during early development of muscle tissue |
|
Definition
| 1. Mesenchymal cells differentiate into myoblasts; 2. Myoblasts can remain as myoblasts or become satellite cells; 3. Myoblasts form the primitive myotube; 4. Satellite cells get into the muscle cell membrane and then just lie dormant waiting for injury; 5. Meanwhile, myoblasts form actin and myosin filaments; 6. during muscle cell injury, staellite cells differentiate to formmyoblasts and then myotube to produce real muscle tissue |
|
|
Term
| what is dissolution in a muscle? |
|
Definition
| breaking up of actin and myosin filaments |
|
|
Term
| what causes dissolution of contractile elements in a muscle |
|
Definition
|
|
Term
| what happens in muscle tissue after dissolution |
|
Definition
| macrophages enter the muscle fiber to remove debris while myoblasts roduce new muscle fiber material |
|
|
Term
| how do myoblasts produce new muscle fiber |
|
Definition
| myoblasts fuse to form myotube. Myoblasts in the myotube form actin and myosin filaments. |
|
|
Term
| if the myoblasts were not creating new actin and myosin filaments = new sarcomeres, what would fill the void? |
|
Definition
|
|
Term
| what does newly regenerated muscle tissue initially look like? |
|
Definition
| atrophied: decreased cross-sectional area and decreased muscle fibers |
|
|
Term
| what is the result of having decreased cross-sectional area in regenerated muscle tissue? |
|
Definition
| decreased maximum tension capability |
|
|
Term
| what is the result of having decreased number of muscle fibers in regenerated muscle tissue? |
|
Definition
|
|
Term
| can you rehabilitate regenerated muscle tissue? |
|
Definition
| yes, with ttime the muscle can hypertrophy. You can increase cross-sectional area, increase maximum tension capability, icnrease number of muscle fiebrs, and decrease fatigue. |
|
|
Term
| what influences the repair of sharply incised muscle tissue or big time muscle strain injury? |
|
Definition
| proximity of tissue defect margins: if you have a strain with a big gap between the 2 parts, scar tissue will want to fill in the gap |
|
|
Term
| what does Jarvinen call the 2 ends of muscles that are separated from each other by injury? |
|
Definition
|
|
Term
| what is necessary for optimum healing of muscle injury to reduce scar tissue formation between stumps |
|
Definition
| close approximation so that myotubes can bridge through scar tissue |
|
|
Term
| when gaps between stumps are too large, what will happen |
|
Definition
| dense connective scar tissue will come in |
|
|
Term
| do we want the muscle stumps to touch |
|
Definition
|
|
Term
| when there is a big gap in muscle such as from laceration injury, what tends to happen |
|
Definition
| recovery is rarely complete. The myotubes try to form, but they can't get through the dense connective tissue. |
|
|
Term
| how can formation of scar tissue be prevented |
|
Definition
| by controlling swelling and inflammation soon after muscle injury |
|
|
Term
| how to control swelling and inflammation in muscle injuries |
|
Definition
| Ice for serveral days. Immobilize the joints in a position to shorten muscles and put the stump edges right next to each other. Keep the muscles quiet in this shortened position. |
|
|
Term
| How long do you need to ice, immobilize in shortened position, and keep muscles quiet after injry? |
|
Definition
|
|
Term
| is it ok to take NSAIDs after muscle injury and why? |
|
Definition
| No NSAIDS right away because NSAIDs inhibit platelet action. We need platelets so that bleeding is not prolonged. |
|
|
Term
| When is it ok to give NSAIDs |
|
Definition
|
|
Term
| when is it time to start moving the muscle after immobilization following injury |
|
Definition
|
|
Term
| how to first move a muscle that has been immobilized after injury |
|
Definition
| 1. warm up the tissue; 2. passively move the muscle; 3. tell the patient: we have to be careful. I'm going to move you, but tell me if you feel any pain. We do not want to go so far that we pull the stumps apart; 3. move them very slowly until their eyes or words tell you that's enough for the day; 5. then they go back to the sling or immobilizer until the next day when you repeat the process |
|
|
Term
| how long do you need to do this slow passive mobilization before the patient's muscle can start doing some business |
|
Definition
| for DAYS. Until you get them passively into full ROM. |
|
|
Term
| what should the first type of muscle contractoin be? |
|
Definition
| gentle concentric-eccentric |
|
|
Term
| why don't you want to do gentle isometrics with patients who have had muscle injury |
|
Definition
| patients might co-contract so that they are not movign a lot but are still producing a lot of muscle force |
|
|
Term
| how to promote gradual increase of muscle strength without creating scar tissue at the injury site, per Jarvinen |
|
Definition
| 1. heat the muscle to make it stronger and more extensible prior to exercise; 2. give them a pen/pencil. "bend your elbow up and lower it down." They won't co-contract. They will activate their elbow flexor muscles just enough; 3. Start them in a semi-recumbant/supine position so that they're not even doing the entire weight force of the extremity. |
|
|
Term
| how often to do these non-functional concentric-eccentric contractions in a recovering muscle? |
|
Definition
| every other day until they can eventually lift major weights, and then they don't need you any more |
|
|
Term
| why do patients get scar tissue at the injury site? |
|
Definition
| they don't use the jarvinen approach |
|
|
Term
| if you have a patient who keeps getting multiple tears, what does that imply |
|
Definition
| scar tissue at the injury site |
|
|
Term
| what to do with a patient who has scar tissue at the injury site that is causing multiple tears? |
|
Definition
| try to make this a mobile, strong scar with a strong scar-muscle interface |
|
|
Term
| how do you make the scar mobile with a good scar-muscle interface? |
|
Definition
| 1. apply eat; 2. load progressively with more load each day until they can hoist massive amounts of load |
|
|
Term
| how does increasing load to the muscle help when there is scar formation? |
|
Definition
| the loading can cause hypertrophy of the scar as well as hypertrophy and organization of the scar-muscle interface |
|
|
Term
| how to do Jarvinen for a hamstrings muscle strain? |
|
Definition
| hinge brace with heel close to the buttocks. Sling to support the weight of the LE and keep all LE muscles quiet |
|
|
Term
| what will happen if you don't put the heel way up close to the buttocks after hamstrings strain |
|
Definition
| stumps will not approximate |
|
|
Term
| what will happen if you don't use a sling to support the weight of the LE after hamstrings muscle strain? |
|
Definition
| muscles that cross the hip and knee have to contract to support the weight of the LE |
|
|
Term
| what is the one summary cause of human compartment syndrome |
|
Definition
| too much pressure in the container |
|
|
Term
| what etiologies cause compartment syndrome |
|
Definition
| abnormally tight fascia, hematoma, normal swelling of compartmental soft tissue associated with exercise, excessive activation of mucsle associated with movement patterns or equipment |
|
|
Term
|
Definition
| a bleed that takes up space and drives up pressure |
|
|
Term
| what to do if you ever see a patient with contusion to muscles in a compartment? |
|
Definition
| minimize the bleed right away: use ice and ACE wrap to decrease swelling and decrease risk of compartment syndrome down the road |
|
|
Term
| what happens that exercise causes swelling of compartmental soft tissue? |
|
Definition
| increased bloodflow to the muscle from excessive exercise |
|
|
Term
| when might you see the anterior compartment muscles such as tibialis anterior doing too much business? |
|
Definition
| could be because the person is a bouncy runner who runs too heavily on her heel or could be because the posterior calf muscles are tight and the anterior muscles have to work against them |
|
|
Term
| how do you know for sure that it is anterior compartment syndrome? |
|
Definition
| with great predictability, the person will do an activity and at X minutes or X mileage, there is enough swelling to cause symptoms. |
|
|
Term
| what is normal capillary pressure? |
|
Definition
|
|
Term
| what happens when capillary pressure goes above 30 mmHg? |
|
Definition
| capillaries shut down, causing ischemic injury to muscle tissue |
|
|
Term
| how do surgeons make the call of compartment syndrome and determine need for fasciotomy? |
|
Definition
| pressure catheter monitoring of the compartment while the person does the exercise that brings on the trouble. |
|
|
Term
| at what compartment pressure is compartment syndrome diagnosed? |
|
Definition
| 10-30 mm HG below diastolic blood pressure |
|
|
Term
| how does immobilization affect muscle tissue |
|
Definition
| greater number of ruptures after return to activity following immobilization |
|
|
Term
| how does mobilization of muscle tissue affect the tissue? |
|
Definition
| greater ultimate strength, greater stiffness, greater energy at failure |
|
|
Term
| what happens if you do too much mobilization in injured muscle tissue? |
|
Definition
| too much too soon increases inflammation and promotes scar formation. |
|
|
Term
| is doing too much after muscle injury more problematic in younger or older people and why? |
|
Definition
| more problematic in younger people because they have more blood flow so they get an even bigger inflammatory response |
|
|
Term
| what is the benefit of being young when you have a muscle injury? |
|
Definition
| greater regeneration of muscle fibers and earlier resorption of hematoma |
|
|
Term
| what is the problem of edema in muscle injuries |
|
Definition
| too much edema can induce ischemic injury to surrounding uninjured muscle tissue by increasing pressure and shutting downs mall capillaries. |
|
|
Term
| what is a negative side effect of pain, edema, fluid following muscle injury |
|
Definition
| reduced movement leading to contracture |
|
|
Term
| what is the longterm result of excess edema from muscle injury |
|
Definition
| increased area of injury, increased area of scar tissue, reduced muscle masss |
|
|
Term
| how to treat early muscle strains |
|
Definition
| early, controlled mobilization following inflammatory phase to facilitate formation of strong scar tissue for scar tissue that forms. Massage to release adhesions that may elicit continual inflammatory episodes during rehabilitation. |
|
|
Term
| what to do before exercise of muscle strain and why |
|
Definition
| warm tissue toimprove short term ultimate strength and extensibility |
|
|
Term
| what to do in the first few days afte rmuscle strains |
|
Definition
| immobilize to prevent formation fo excessive scar tissue and faciliate formation of normal muscle fibers across the site of injury |
|
|
Term
| what to do after the first few days of immobilization after muscle strain |
|
Definition
| controlled mobilization to facilitate stronger muscle tissue |
|
|
Term
| describe protection of muscle tissue after strain |
|
Definition
| the muscle tissue is mechanically weaker and requires protection related to intensity, frequency, and duration of loading |
|
|
Term
| how to control inflammation in muscle initially after injury? |
|
Definition
| RICE, NSAIDs after 2 days |
|
|
Term
| how do NSAIDs help with healing muscle strain |
|
Definition
| NSAIDs decrease inflammation and ischemia from edema. No detrimental effects of NSAIDs on satellite cell |
|
|
Term
| why is it good to control edema? |
|
Definition
| to reduce scar formation and facilitate more pronounced muscle regeneration by satellite cells |
|
|
Term
| describe whether to immobilize in short or long positions and why? |
|
Definition
| during the inflammatory stage 3-5 days: immobilize in a position so that the muscle length is short enough that hyou have confidence that the muscle stumps are approximated to minimize gap and minimize scar tissue. After 3-4 days, immobilize in lengthened position to decrease inflammation and end up with a longer m-t unit that is mechanilally stronger. |
|
|
Term
| when to begin controlled mobilization after muscle injury and why? |
|
Definition
| after the first 3-4 days, after inflammation. Early, controlled mobilization to facilitate formation of strong scar tissue for any scar tissue that forms. |
|
|
Term
| what might eventually be required if scar tissue forms |
|
Definition
| massage to release adhesions |
|
|
Term
| when to massage scar tissue? |
|
Definition
| not to late and not too early. Don’t' want to separate the muscle stumps |
|
|
Term
| when to start warming tissue? |
|
Definition
|
|
Term
| what does warming do to muscle tissue? |
|
Definition
| increases extensibility, increaes ultimate strength (short term) |
|
|
Term
| how to progress magnitude of frequency, intensity, duration? |
|
Definition
|
|
Term
| what are extrinsic factors that can lead to hamstring muscle strain |
|
Definition
| inadequate warm-up, fatigue, reduced fitness level |
|
|
Term
| why does inadequate warm-up put you at risk for hamstring injury |
|
Definition
| when the tissue is cold, it is mechanically weaker and can't stretch as much |
|
|
Term
| why does reduced fitness level put you at risk for hamstring muscle strain |
|
Definition
| approach angle of the collagen fibers is larger |
|
|
Term
| what are intrinsic risk factors for hamstring muscle strain |
|
Definition
| strength deficits, reduced flexibility, age |
|
|
Term
| why is older tissue more likley to fail? |
|
Definition
|
|
Term
| why is weaker/less flexible tissue more likley to fail? |
|
Definition
| can't go as foar on stress-strain curve |
|
|
Term
| describe how the hamstring to quads strength ratio influences risk of hamstring injury |
|
Definition
| during the initiation of swing phase of running, the quads produce knee extension force. If the hams aren't strong relative to quads, they can't generate sufficient eccentric tension to declerate the leg and foot and will become injured in the process |
|
|
Term
| why does previous muscle injury put you at risk for future muscle injury? |
|
Definition
| probably because you didn't use Jarvinen and have a lot of scar tissue AND because you returned to activity to quickly |
|
|
Term
| why does running with a flexed trunk put you at risk for hamstring strain |
|
Definition
| you are passively stretching the hams when you run with a flexed trunk |
|
|
Term
| how to prevent hamstring muscle strains |
|
Definition
| eccentric hamstring strengthening, WB strength training, stretch when muscle fatigued. Greatly reduces risk factor |
|
|
Term
|
Definition
| massage to decrease soreness, heat to decrease pain, compression garments, gentle movement such as yoga, NSAIDs, counter-irritant cream to decrease pain |
|
|
Term
| how do counter-irritant creams work |
|
Definition
| they increase bloodflow to the skin, warms you up |
|
|
Term
| does ultrasound help DOMS |
|
Definition
|
|
Term
|
Definition
|
|
