Energy & Oxygen for Muscle Contraction

Where is energy needed

Energy is needed in three(3) places› At the cross-bridges for movement

Sliding Filament Mechanism› At the cross-bridge & Actin binding site

To break connection › At the Sarcoplasmic Reticulum

To pump Ca+ back into the S.R.

Energy Sources for Muscle Contraction

ATP› Best source of energy› Only last about 3-5 seconds on the body

and is used even faster. Creatine Phosphate

› 4 6 times more abundant in the body than ATP.

› Is broken down to make ATP.› Can provide enough energy to sustain

muscle contraction for about 15 seconds.

Energy Sources for Muscle Contraction Cont…

Glycogen› Stored form of Glucose (sugar)› Is broken down to make ATP.› Can provide enough energy to sustain

muscle contraction for several mins. Fat

› The body will turn to fat as a source of energy for muscle contraction when the contraction is for a prolonged strenuous activity and when the other sources of energy have been used up.

Oxygen Supply Oxygen is required for cells to make ATP.

› Cellular Respiration: process that makes ATP.› Fermentation: process that makes ATP without

oxygen. Oxygen Debt: If the cells doesn’t have

enough oxygen carry out respiration it shifts to fermentation.› Lactic Acid is a by-product of fermentation and

can build up in the cell, it also requires oxygen to be broken down.

› Heavy Breathing, Muscle Cramps, Muscle Spasms

› Muscle Fatigue: The inability for a muscle to contract in a normal manner.