⚽ Year 9 Physical Education

Biomechanics, exercise physiology, periodisation, tactical analysis, and health promotion.

Biomechanics

Forces and Motion in Sport

  • Biomechanics: the application of mechanical principles to living organisms — understanding how forces affect the body and sporting movements
  • Net force: the resultant of all forces acting on an object. If net force = 0, the object remains stationary or at constant velocity (Newton's 1st Law).
  • Reaction force: every force has an equal and opposite reaction (Newton's 3rd Law). Runners push back on the ground; the ground pushes them forward.

Centre of Mass and Balance

  • Centre of mass (CoM): the point at which an object's mass is concentrated. In a symmetrical human body, it is roughly at the level of the navel.
  • Stability: an object is stable if its centre of mass is over its base of support. A wider base of support and lower CoM = greater stability.
  • Sporting application: a sumo wrestler has a wide stance (wide base) and a low centre of mass → very stable. A sprinter in the starting blocks intentionally has an unstable position (CoM near the edge of the base of support) to accelerate quickly.
  • Levers in the body: muscles apply forces via lever systems. The three classes of lever (1st, 2nd, 3rd) determine mechanical advantage — whether the lever is designed for force or for speed/range of motion. Most levers in the body are 3rd class (effort between fulcrum and load): sacrifice force but gain speed and range. Example: elbow flexion (bicep curl) — fulcrum = elbow joint, effort = biceps muscle, load = forearm/weight.

Projectile Motion

  • A projectile follows a parabolic path under gravity (ignoring air resistance)
  • Factors affecting range: angle of release (45° gives maximum range in theory), speed of release, height of release
  • In sport: a javelin, shot put, basketball free throw, tennis ball — all follow projectile paths
  • Spin: backspin reduces range; topspin increases range due to the Magnus effect (pressure difference created by spinning ball curving through air)

Exercise Physiology

Energy Systems

  • ATP (adenosine triphosphate): the universal energy currency of the body. When the phosphate bond is broken, energy is released. ATP must be continuously resynthesised.
  • ATP-PC (phosphocreatine) system: immediate, anaerobic. Phosphocreatine in muscles donates a phosphate to ADP to reform ATP. Lasts ~10 seconds. Used in explosive, maximal efforts: 100m sprint, power lifting.
  • Lactic acid (glycolytic) system: short-term, anaerobic. Glucose broken down to pyruvate → lactic acid. Lasts ~90 seconds. Used in high-intensity activities: 400m, 200m, repeated sprints.
  • Aerobic system: long-term, requires oxygen. Glucose (and fats, proteins) fully oxidised via the Krebs cycle and electron transport chain. Produces much more ATP but more slowly. Used in sustained activities: marathon, football, cycling.
  • The three systems work simultaneously; the dominant system depends on the intensity and duration of exercise.

The Lactate Threshold

  • Lactate threshold: the exercise intensity above which lactic acid begins to accumulate in the blood faster than it can be removed
  • Training can raise the lactate threshold — meaning athletes can work at higher intensities before "going anaerobic"
  • Signs of exceeding lactate threshold: burning sensation in muscles, rapid breathing, fatigue

Effects of Training — Cardiac Adaptations

  • Cardiac hypertrophy: the heart muscle gets larger and stronger (especially the left ventricle)
  • Increased stroke volume: the heart pumps more blood per beat
  • Lower resting heart rate (bradycardia): a trained athlete may have a resting HR of 40–50 bpm (vs 70 bpm average)
  • Increased cardiac output at maximal exercise: more blood (and therefore oxygen) delivered to working muscles
  • VO₂ max: the maximum rate at which the body can consume oxygen during maximal exercise. The best single measure of aerobic fitness. Improved by endurance training.

Periodisation & Training Planning

What Is Periodisation?

  • Periodisation: the systematic planning of training to peak performance for a specific time (e.g. a major competition) while managing fatigue and preventing overtraining
  • Used by elite athletes and their coaches to organise training into structured cycles

Macrocycle, Mesocycle, Microcycle

  • Macrocycle: the longest planning period, typically a year or Olympic cycle (4 years). Contains the athlete's main goal (e.g. World Championships).
  • Mesocycle: blocks within the macrocycle, typically 4–8 weeks. Each mesocycle has a focus: general preparation → specific preparation → competition → transition (recovery).
  • Microcycle: the shortest cycle, typically a week. Contains the specific training sessions with volume and intensity planned.

Phases of Training

  • Off-season (transition): active rest; recovery from the season; low-intensity cross-training
  • Pre-season (preparation): building general fitness base — high volume, moderate intensity
  • Competition season: maintaining fitness, sharpening skills, reducing volume while maintaining intensity to allow recovery
  • Tapering: reducing training load in the 1–3 weeks before a major competition to allow the body to fully recover and "supercompensate" — performing better than ever
  • FITT principle applied per phase: adjust Frequency, Intensity, Time, and Type of training to meet the phase's goals

Tactical Analysis

Game Intelligence

  • Tactical awareness: understanding the patterns of play, reading the game, anticipating opponents' actions, making the right decision under pressure
  • Decision-making: elite performance is as much mental as physical. Experienced athletes process situations faster and select optimal responses.
  • Information processing model: stimulus → sense organs → short-term sensory store → perception → decision-making → response → movement
  • Reaction time can be improved by: practice and experience (automating responses), reducing the number of choices (reducing information overload), mental rehearsal (visualisation)

Team Formations and Strategies

  • Football: 4-4-2 (balanced), 4-3-3 (attacking), 5-3-2 (defensive), high press (pressing the opposition high up the pitch to win the ball early)
  • Basketball: man-to-man vs zone defence; pick-and-roll offense; fast break (transitioning quickly from defence to offence)
  • Principles applicable to all sports: width (use the full space), depth (support behind and in front of the ball), mobility (movement to create space), improvisation

Analysing Performance

  • Notational analysis: recording occurrences of specific actions during a game (shots, tackles, passes, errors) to identify patterns
  • Video analysis: reviewing footage to analyse technique, positioning, and decision-making
  • Performance profiling: comparing an athlete's current skill levels against an ideal profile to identify areas for improvement
  • SWOT analysis: Strengths, Weaknesses, Opportunities, Threats — applied to team or individual performance

Health, Fitness & Lifestyle

The Health Triangle

  • Health has three interconnected dimensions: physical (body function), mental (psychological wellbeing), and social (relationships and community)
  • True health requires all three dimensions to be in balance — illness in one affects the others
  • WHO definition of health: "a state of complete physical, mental, and social well-being, and not merely the absence of disease"

Non-Communicable Diseases (NCDs) and Physical Activity

  • NCDs (lifestyle diseases): type 2 diabetes, cardiovascular disease (coronary heart disease, stroke), obesity, some cancers, osteoporosis
  • Physical activity reduces risk of: cardiovascular disease (up to 35% lower risk with regular activity), type 2 diabetes (up to 40%), colon cancer (up to 30%), depression (up to 30%), dementia
  • UK guidelines: children and young people should do at least 60 minutes of moderate-to-vigorous activity per day; adults at least 150 minutes of moderate or 75 minutes of vigorous activity per week, plus muscle-strengthening activities on 2+ days

Sedentary Behaviour

  • Sedentary behaviour: time spent sitting or lying down (not sleeping) — screen time, desk work, commuting
  • Even people who meet exercise guidelines but sit for many hours are at increased health risk
  • "Sitting is the new smoking" — though this is a simplification, prolonged sitting is independently associated with poor health outcomes
  • Breaking up sedentary time (e.g. standing up every 30 minutes) has measurable health benefits