7) Muscle soreness and muscle cramps Flashcards

Question

# Rhabdomyolysis Rhabdomyolysis: Skeletal mm damage due to several causes including: - **?** - **?** - **?** injury - lack of **?** (prolonged large reduction)

Answer 1

Skeletal mm damage due to several causes including: - **strenuous exercise** - **heat stroke** - **crush injury** - lack of **blood flow** (prolonged large reduction) ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Symptoms: * Muscle swelling * Weak, tender and sore muscles * Dark tea-coloured urine * Decreased urination * Nausea * Loss of consciousness

Answer 2

Symptoms: * Muscle swelling * Weak, tender and sore muscles * Dark tea-coloured urine * Decreased urination * Nausea * Loss of consciousness ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle → release of mm cell contents (electrolytes, myoglobin, creatine phosphokinase, lactate dehydrogenase) into circulation and ecf - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Skeletal mm damage due to several causes including: - strenuous exercise - heat stroke - crush injury - lack of blood flow (prolonged large reduction)

Answer 3

Myoglobin damages kidneys in large quatities; if kidneys cannot get rid of myoglobin fast enough, kidney failure and death can occur ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle → release of mm cell contents (electrolytes, myoglobin, creatine phosphokinase, lactate dehydrogenase) into circulation and ecf - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Skeletal mm damage due to several causes including: - strenuous exercise - heat stroke - crush injury - lack of blood flow (prolonged large reduction)

Answer 4

"Caused by exercise" - Breakdown and necrosis of striated skeletal muscle after engaging in physical activity Seen in spin classes/boot camps - Repetitive use of large mm groups (gluteus maximus and quadriceps muscles) Risk Factors: - intensity of exercise - conditioning of participant - hydration - body temperature ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle → release of mm cell contents (electrolytes, myoglobin, creatine phosphokinase, lactate dehydrogenase) into circulation and ecf - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Skeletal mm damage due to several causes including: - strenuous exercise - heat stroke - crush injury - lack of blood flow (prolonged large reduction)

Answer 5

"Caused by exercise" - Breakdown and necrosis of striated skeletal muscle after engaging in physical activity Seen in spin classes/boot camps - Repetitive use of large mm groups (gluteus maximus and quadriceps muscles) Risk Factors: - intensity of exercise - conditioning of participant - hydration - body temperature ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle → release of mm cell contents (electrolytes, myoglobin, creatine phosphokinase, lactate dehydrogenase) into circulation and ecf - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Skeletal mm damage due to several causes including: - strenuous exercise - heat stroke - crush injury - lack of blood flow (prolonged large reduction)

Answer 6

"Caused by exercise" - Breakdown and necrosis of striated skeletal muscle after engaging in physical activity Seen in spin classes/boot camps - Repetitive use of large mm groups (gluteus maximus and quadriceps muscles) Risk Factors: - intensity of exercise - conditioning of participant - hydration - body temperature - drugs such as NSAIDS because of impact on kidneys ## Footnote Rhabdomyolysis = Breakdown (dissolution) of striated muscle → release of mm cell contents (electrolytes, myoglobin, creatine phosphokinase, lactate dehydrogenase) into circulation and ecf - More extreme than doms Myoglobin - processed in kidney [Myoglobin]+++ → exceeds kidney's handling capacity → kidney blockage → kidney failure - Can test blood for muscle contents (high CPK / LDH) to check for mm damage Skeletal mm damage due to several causes including: - strenuous exercise - heat stroke - crush injury - lack of blood flow (prolonged large reduction)

Answer 7

Exercise associated muscle cramps: a temporary involuntary contraction of skeletal muscle that is intense and painful - can occur during or immediately after muscular exercise or during sleep - Most common in endurance events - Vary in intensity and duration ## Footnote Hard to study in lab (random == hard to induce)

Answer 8

- can occur during or immediately after muscular exercise or during sleep - Most common in endurance events - Vary in **intensity** and **duration** ## Footnote Hard to study in lab (random == hard to induce)

Answer 9

Proposed mechanisms of EAMC: 1. Electrolyte depletion theory: disturbance of water and salt balance 2. Altered neuromuscular control theory ## Footnote Proposed mechanisms of EAMC: 1. Electrolyte depletion theory: disturbance of water and salt balance * Sweating causes spontaneous muscle contractions due to loss of normal resting membrane potential * Cramp is often associated with large sweat losses during prolonged exercise in the heat, but can occur in cool environments with little or no sweat loss * Sweat loss alone and the consequent disturbances of electrolyte balance cannot account for all cramps 3. 2. Altered neuromuscular control theory: * Muscle fatigue causes abnormal activity of the muscle spindle and Golgi tendon organ * Abnormal discharge of alpha motor neuron drive to the afflicted muscles * No prevention strategy or treatment is consistently effective

Answer 10

One Theory behind exercise associated muscle cramps - Disturbance of **water and salt** balance - **Sweating** causes spontaneous MM contractions due to loss of **normal resting membrane potential** - Cramp is often associated with large **sweat** losses during prolonged exercise in the heat, but can occur in cool environments with little or no sweat loss - **Sweat loss** alone and the consequent disturbances of **electrolyte** balance *cannot* account for all cramps ## Footnote 2. Altered neuromuscular control theory: * Muscle fatigue causes abnormal activity of the muscle spindle and Golgi tendon organ * Abnormal discharge of alpha motor neuron drive to the afflicted muscles * No prevention strategy or treatment is consistently effective

Answer 11

One Theory behind exercise associated muscle cramps Altered neuromuscular control theory: * Muscle fatigue causes abnormal activity of the **muscle spindle** and **Golgi tendon organ** (sensory organs) * Abnormal discharge of **alpha motor neuron** drive to the afflicted muscles (as mm fatigues, the muscle spindle and golgi tendon organ fall out of sync) ## Footnote This theory suggests that EAMCs occur when **fatigue** and other risk factors contribute to a final common pathophysiological pathway to produce an **imbalance between excitatory and inhibitory stimuli at the α motor nerve** The muscle spindles and golgi tendon organs are proprioceptive sensory organs: - muscle spindle: senses the changes in muscle **length** and the rate of lengthening - Golgi tendon organ: senses the changes in muscle **tension**