Fibres & Motor Units
Which muscle fibre type is red, slow contracting and resistant to fatigue?
Type 1 (slow-twitch oxidative
Which major muscle group on the front of the thigh extends the knee?
Quadriceps
Which structure is injured in a sprain?
Ligament (a strain is muscle or tendon)
Which piece of protective equipment do players wear in junior AFL?
Mouthguard (prevents dental and jaw injuries)
Describe fartlek training.
Continuous aerobic activity with surges of higher intensity throughout the session, such as a faster pace or running up a hill (e.g. stride hard 30 seconds, jog 90 seconds, repeat)
Name the two parts of the sliding filament model which make the sarcomere shorten.
Actin and myosin
Name the type of contraction where a muscle lengthens under tension, such as the biceps lowering a weight.
Eccentric
Classify as direct or indirect: a netballer slips on a wet court and twists her knee.
Indirect, as it’s caused by an internal force with no collision.
State two aims of a cool down.
Any two: prevent venous pooling; remove metabolic waste (e.g. lactic acid) faster; reduce muscle soreness; return the body to its resting state faster.
State two chronic muscular adaptations to anaerobic training.
Any two: muscular hypertrophy; more and larger myofibrils; increased ATP, CP and glycogen stores; increased glycolytic capacity; faster and stronger contractions; greater tolerance of metabolic by-products.
Describe how calcium and ATP allow a sarcomere to shorten.
Calcium binds to troponin, which moves tropomyosin off the binding sites on actin. ATP breakdown to ADP lets the myosin cross bridges attach to actin and pull it towards the centre
In a bicep curl, identify the agonist and antagonist and the role of each.
Agonist: biceps brachii, which shortens to flex the elbow. Antagonist: triceps, which relaxes and lengthens to allow the movement.
Describe an overuse injury and give one example of overtraining that could cause one.
Caused by excessive, repeated use of the same muscle, bone or joint, with inflammation, pain and slow recovery. Overtraining examples: too little recovery between sessions, excessive training load, or inappropriate increases in frequency, duration or intensity.
Identify the two phases of a warm up and describe what should be included in each phase.
Beginning of a warm up / general phase
Include low to moderate intensity cardiovascular, whole body activities that are continuous in nature, such as jogging, cycling or swimming.
include dynamic stretching
Sport / activity-specific phase
Include activities that involve agility, speed and acceleration and are directly related to the muscles, joints and body parts about to be used in the activity
Should an athlete eat low-GI or high-GI carbohydrates before an event, and why?
Low-GI, because it is digested and absorbed slowly, giving a sustained release of glucose during activity.
Explain the all-or-nothing principle.
The nerve impulse must reach a threshold before it stimulates the fibres. Once it does, all fibres in that motor unit contract maximally at the same time. If it’s too weak, none contract.
Hamstring tears can happen when the quadriceps and hamstrings contract at the same time. Explain why the hamstrings are the muscle that tears.
Normally the agonist contracts while the antagonist relaxes (reciprocal inhibition). Neural misfiring makes both contract, and the more powerful quadriceps overpower the weaker hamstrings, which tear.
Describe osteoporosis and explain how weight-bearing activity helps reduce the risk.
Bone loses minerals (especially calcium) faster than they’re replaced, so bone becomes thin, weak and fragile, with a higher fracture risk. Weight-bearing PA maintains or improves bone density and strengthens the muscles attached to bone, improving posture and balance and reducing falls.
Explain how a warm up reduces the risk of a muscle strain.
It raises heart rate and blood flow, which increases muscle temperature.
This increases the elasticity of muscle fibres and tendons and enzyme activity, so the muscle is less likely to tear under sudden stress.
Dylan, a footballer, wants better short-burst sprint speed.
Identify a suitable training method and describe what it is and how it would lead to better short-burst sprint speed.
Short or intermediate interval training: set periods of high-intensity work followed by set rest or recovery, repeated several times. It improves speed, power, anaerobic capacity and agility.
(Plyometric or resistance training are also acceptable if explained.)
Justify why the body recruits small motor units before large ones when going from a walk to a sprint.
Small units are easily excited, slow contracting and fatigue resistant, so they suit low-force, prolonged work. As force demand rises, larger units are added: fast contracting, high threshold, high force, but they fatigue quickly. This matches force to demand and saves the fatigable units for when they’re needed.
Justify why most levers in the human body are third-class levers, with reference to speed.
Force is applied between the axis (joint) and the resistance. Because the force is close to the axis, the resistance end moves through a bigger range of motion (e.g. quadriceps, knee, foot in a kick). This leads to an increase in speed and momentum when moving the lever. This is called mechanical disadvantage, as more force is needed to move the lever.
Justify why regular low-impact physical activity is recommended for someone with osteoarthritis.
Cartilage wears away so bones rub together, causing pain and stiffness. Low impact PA (e.g. water-based) avoids repetitive stress on the joint and PA in general improves joint mobility and flexibility, strengthens the muscles supporting the joint, improves posture and balance, reduces pain and fatigue, and helps maintain a healthy weight (a risk factor).
A hockey player has a previously sprained ankle. Justify whether taping or a brace is the better choice.
Both restrict harmful movement while allowing desired movement, stabilise the joint on landing, and enhance proprioceptive feedback after previous injury.
A brace can be put on by the athlete themselves, whereas effective taping must be applied by someone else.
Justify = explain why and provide evidence
An athlete argues that anabolic steroids are no different from protein powder and creatine, because all three help build muscle and speed up recovery. Evaluate this argument.
Strenght of Argument:
All three aim to increase strength, power and recovery. Protein supports muscle protein synthesis and repair, and creatine helps regenerate ATP, so athletes can train harder.
Weakness of argument: protein and creatine are permitted, and their benefits and harms are comparatively mild (e.g. weight gain, GI upset, extra kidney load from excess protein).
Protein has no advantage over food as part of a balanced diet.
Steroids are prohibited because they artificially enhance performance, harm health (e.g. tendon injury, liver damage, hypertension, mood swings, infertility) and go against the spirit of sport.
Conclusion: the argument is weak, because permitted methods work within the body’s normal limits and carry far lower risk.