Slow Oxidative Fast Oxidative Fast Glycolytic Fibres Fibres Glycolytic Fibres FG - Type IIb SO – Type I FOG - Type IIa Structural variations Colour & Size Red & small Red/Pink / intermediate White/pale & large No of mitochondria Many Few No of capillaries Many Many Myoglobin concentrate High Low Glycogen Stores Low Intermediate High Functional variations Contractile speed Fast Fast Contractile strength Low Intermediate Fatigue resistance High Low Aerobic capacity Moderate Anaerobic capacity Low High Best suited activities Endurance, low Activities involving both High intensity, low intensity, high low & high duration & duration, speed/power duration activity intensity activities Examples...... Exam question The muscle fibre type that would be used during a maximal muscle contraction is the fast glycolytic (type IIb) fibre. Give two structural & two functional characteristics of this type of muscle fibre. [4 marks] Take it further - Cut out a picture of three different performers and predict which muscle fibre type they are more likely to have a higher percentage of. Justify your answer with structural & functional characteristics of muscle fibres shown above. Warm Up & Cool Down Warm Up and Cool downs are crucial in sport. Muscles contain elastin, a protein which has an elastic property and a coiled effect, so that when you stretch muscle tissue, it returns to its original length. However, the warmer the muscle becomes, it will be able to stretch further and recoil with greater force, therefore performing better. You need to know the physiological effects of a warm-up and cool-down on skeletal muscle.. Warm Up Cool Down Increase speed & force of contraction Faster removal of lactic acid from fast due to higher speed of nerve transmission twitch fibres Improved economy of movement due to a A decrease in the risk of DOMS
Slow Oxidative Fibres SO – Type I Fast Oxidative Glycolytic Fibres FOG - Type IIa Fast Glycolytic Fibres FG - Type IIb Structural variations Colour & Size No of mitochondria No of capillaries Myoglobin concentrate Glycogen Stores Red & small Many High Low Red/Pink / intermediate Many Many Intermediate White/pale & large Few Low High Functional variations Contractile speed Contractile strength Fatigue resistance Aerobic capacity Anaerobic capacity Low High Low Fast Intermediate Moderate Fast Low High Best suited activities Examples...... Endurance, low intensity, high duration activity Activities involving both low & high duration & intensity High intensity, low duration, speed/power activities Exam question The muscle fibre type that would be used during a maximal muscle contraction is the fast glycolytic (type IIb) fibre. Give two structural & two functional characteristics of this type of muscle fibre. [4 marks] Take it further - Cut out a picture of three different performers and predict which muscle fibre type they are more likely to have a higher percentage of. Justify your answer with structural & functional characteristics of muscle fibres shown above. Warm Up & Cool Down Warm Up and Cool downs are crucial in sport. Muscles contain elastin, a protein which has an elastic property and a coiled effect, so that when you stretch muscle tissue, it returns to its original length. However, the warmer the muscle becomes, it will be able to stretch further and recoil with greater force, therefore performing better. You need to know the physiological effects of a warm-up and cool-down on skeletal muscle.. Warm Up Cool Down Increase speed & force of contraction Faster removal of lactic acid from fast due to higher speed of nerve transmission twitch fibres Improved economy of movement due to a A decrease in the risk of DOMS
79CA45B32B273B802856C2F5F453657C.docx