Comparison of different types of muscles

Dr. Shaikh Mujeeb AhmedAssistant Professor

Department Basic Medical Sciences Division of Physiology Faculty of Medicine Almaarefa Colleges

بسم الله الرحمن الرحيم

Spot the Difference

Metabolic Systems

Phosphocreatine-Creatine System

• Quicker - 4 moles of ATP per min.• Maximum muscle power for 8-10 seconds.• Used mainly in 100 meter run.

Glycogen Lactic Acid System

• Stored glycogen split into glucose & then glucose to energy.

• Anaerobic metabolism• 2.5 times as rapid as oxidative mechanism.• Short to moderate period, 1.3 – 1.6 min of

maximum muscle activity

Aerobic System

• Oxidation of food stuff in mitochondria.• Moles of ATP per min are 1/min.• Maximum muscle power for as long as

nutrients last.• Marathon run.

Major Types of Muscle Fibers

• Classified based on differences in ATP hydrolysis and synthesis

• 3 major types– Slow-oxidative (type I) fibers– Fast-oxidative (type IIa) fibers– Fast-glycolytic (type IIx) fibers

Percentage of fast twitch and slow twitch fibers in quadriceps muscle

Fast Twitch• 18%• 26%• 55%• 63%• 63%

Slow Twitch• 82%• 74%• 45%• 37%• 37%

• Marathoners• Swimmers• Weight lifters• Sprinters • Jumpers

References

• Human physiology by Lauralee Sherwood, 7th edition

• Text book physiology by Guyton &Hall,12th edition

• Text book of physiology by Linda .s contanzo,third edition

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