Caffeine aids in the movement of calcium ions across cell membranes by both making it easier for the Ca2+ channels to open and by holding the channels open longer. How would the administration of caffeine to a muscle fiber affect its contraction?

Caffeine cause dose dependent prominent increase in force of contraction and period of contraction of muscle

Explanation:

Caffeine is widely used in foods and drinks. Its long time use can effect central nervous system include lethargy memory, sleep disorder and anxiety.

Increase in concentration of calcium ion will result increase number of power stroke and force for contraction.  However latent period and relaxation period are unaffected by caffeine. Increase in concentration of calcium ion will result increase number of power stroke and force for contraction.

Because of calcium ion release in skeletal muscle, caffeine causes peripheral manifestation such as hyper-reflexia, muscle twitching etc.

High amount of caffeine leads to increase in release of Ca2+ from sarcoplasmic reticulum. It increases tension development in single tetanic contraction and re-initiate maximum tension in fatigue single myofibre by restoring Ca2+ release from sarcoplasmic reticulum to non-fatigued levels.

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