Which enzyme is commonly elevated with skeletal muscle activity?

Which enzyme is commonly elevated with skeletal muscle activity?

• A. ALT
• B. CK
• C. GGT
• D. Amylase

Answer: (B)

When skeletal muscle is stressed or damaged, enzymes stored in muscle cells leak into the bloodstream. Creatine kinase is the enzyme most commonly elevated in this situation, with the CK-MM isoform predominating in skeletal muscle. Its levels rise within hours of intense activity or injury and typically peak in 24–72 hours, remaining elevated for several days depending on the extent of damage. This makes CK a sensitive marker of muscle injury, including conditions like rhabdomyolysis and various myopathies. Other enzymes listed are more specific to liver (ALT, GGT) or pancreas/salivary glands (amylase) and are not characteristic indicators of skeletal muscle activity, so creatine kinase best fits the scenario.

When skeletal muscle is stressed or damaged, enzymes stored in muscle cells leak into the bloodstream. Creatine kinase is the enzyme most commonly elevated in this situation, with the CK-MM isoform predominating in skeletal muscle. Its levels rise within hours of intense activity or injury and typically peak in 24–72 hours, remaining elevated for several days depending on the extent of damage. This makes CK a sensitive marker of muscle injury, including conditions like rhabdomyolysis and various myopathies. Other enzymes listed are more specific to liver (ALT, GGT) or pancreas/salivary glands (amylase) and are not characteristic indicators of skeletal muscle activity, so creatine kinase best fits the scenario.