Presentation on theme: "Suggest a mix for the sportspeople shown below."— Presentation transcript:
1Suggest a mix for the sportspeople shown below. Muscle twitch fibresMuscle twitch fibres occur in different proportions in different people.This proportion is mainly to do with the genes you inherit.The proportion can be altered to some extent by training.Suggest a mix for the sportspeople shown below.Suggested answer:Marathon runner 75% slow twitch / 25% fast twitchWrestler 75% fast twitch / 25% slow twitch
7Muscle endurance training Muscular endurance means the ability of muscles to repeatedly contract without getting tired.Muscular endurance can be improved by moving a lighter weight many times.Muscles become better at using oxygen and long-term energy stores (especially fat) and work better over long periods of time.Muscular endurance is important in events like long distance running, cycling and rowing which take a long time to complete.
11Muscle tone and posture Muscles almost never fully relax – even when you sleep, there are always some fibres in a state of partial tension. This is called muscle tone.Exercise improves your muscle tone – it causes more of your muscle fibres to be slightly tensed, ready for action.Poor muscle tone leads to poor posture and slouching.Rounded shouldersCurved backHere are some examples you could use with your class:You need muscle tone to stand up straightGravity will try to push your head down and forward – muscle tone will keep it upright unless you are unconscious.If shoulders are drooped this can indicate a weak trapezius and therefore poor muscle tone.Maintaining muscle tone requires energy.
12Posture If you have good posture… But if you have poor posture… Your internal organs, like your heart and digestive system, will function more effectively because good posture creates more space in the chest and abdomen.Straight shoulders allow more room in the chest, so lung capacity is increased.Good posture helps prevent strain and injury in everyday activity and sport.Other muscles have to work harder to compensate for weak muscles. You will get tired sooner.You don’t look as good. This may damage your self-esteem.
14Exam-style questions1. This picture shows part of the muscular system.Name muscles a–e.abJanine exercises her deltoids by lifting heavy weights. She raises her arms out to the sides until her hands are level with her shoulders.cdeWhat type of movement is occurring at the shoulder?What type of muscle contraction is involved?Janine changes her exercise to holding the weights out to the sides at shoulder level for 10 seconds at a time.a) a = trapezius; b = deltoid; c = latissimus dorsi; d = tricep; e = gluteal. b) abduction. c) isotonic d) static strengthd) What type of strength will this improve?
15Exam-style questions2. Explain what is meant by an antagonistic pair and give one example.Muscular endurance can be improved by training.Andrew is trying to improve his muscular endurance. He performs five biceps curls a day with a very heavy weight. Andrew’s muscular endurance is not increasing much.What is meant by muscular endurance?How is muscular endurance important in everyday life?An antagonistic pair are a pair of muscles that work together to move a joint. As one contracts and shortens, the other relaxes and lengthens, causing movement. The muscles swap roles to achieve the opposite movement. The biceps and triceps are the antagonistic pair that operate the elbow joint.a) Muscular endurance is the ability of muscles to contract repeatedly without getting tired. b) Muscular endurance is important in the performance of many everyday tasks like gardening and DIY. People with poor muscular endurance can find these tasks very tiring. C) Andrew’s exercises will improve his strength rather than his muscular endurance. He should use a lighter weight and increase the number of repetitions he performs.c) Suggest how he could change his exercise so that he achieves better results.
16Can you remember all these keywords? Voluntary muscleInvoluntary muscleCardiac muscleAntagonistic pairOriginInsertionExtensorFlexorFast twitchSlow twitchIsotonic contractionIsometric contractionHypertrophyAtrophyResistanceMuscular enduranceMuscle tonePosture