Year 12 – Health and Movement Science

2.3 Examine the relationship between the principles of training, physiological adaptations and improved performance

About the dot point

Training for improved performance is the process of using a planned, structured training programme to apply the right type and amount of stress to body systems so they adapt. When training is applied correctly over time, it produces predictable physiological adaptations in the cardiovascular and muscular systems. These adaptations matter because they improve how well the body can produce energy, deliver and use oxygen, generate force, and resist fatigue, which together lead to better sport-specific performance.

How to approach it

In this dot point, the directive verb is examine. This means you need to look closely and carefully at the relationship between the principles of training, the physiological adaptations they create, and what improved performance looks like in a specific sport. Use the examples and evidence on this page to show a clear cause-and-effect chain, explaining how particular principles (such as specificity, progressive overload, and training thresholds) lead to specific adaptations, and why those adaptations improve performance.

1. Principles of training, physiological adaptations and improved performance

The Training for improved performance focus area explains why a well-designed training programme leads to better results. Training improves performance because applying the principles of training creates predictable physiological adaptations.

Physiological adaptations are long-term changes that increase your capacity to produce energy, move efficiently, generate force, and resist fatigue. In this dot point, each adaptation should be linked to relevant principles of training, then connected to what improved performance looks like in a sport.

Training places repeated stress on body systems. If the stress is frequent, sport-specific, and challenging enough, the body responds by changing its structure and function. These long-term changes, which develop over weeks to months, are physiological adaptations.

To examine means to investigate and explain relationships. In this dot point, you are expected to show a clear cause-and-effect chain linking:

  • the principles of training that were used (and how they were applied)
  • the physiological adaptations those principles create (and why they happen)
  • how those adaptations lead to improved performance in a specific sport

A strong response does not list principles and adaptations separately. It makes the links clear and uses accurate physiology and sport examples.

2. Heart rate

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

An AFL midfielder has an excellent running base but “drops off” late in games and struggles to repeat high-speed efforts after stoppages.
  • Specificity: repeat-effort conditioning that copies AFL work:rest patterns
  • Training thresholds: regular work above aerobic threshold, plus efforts near or above anaerobic threshold
  • Progressive overload: more total high-intensity running or shorter rest periods across weeks
  • Lower resting heart rate
  • Lower heart rate at the same submaximal running speed
  • Faster heart rate recovery
  • Mainly caused by increased stroke volume and stronger parasympathetic control

Better endurance and repeated-effort capacity late in games.

e.g. In AFL, high-speed efforts can be repeated with less drop in intensity because recovery between stoppages is quicker.

2.1 What changes

In training adaptations, heart rate usually refers to changes in resting heart rate, heart rate at a set submaximal workload, and heart rate recovery after exercise.

With regular aerobic training, the heart becomes more efficient. Resting heart rate can fall because stroke volume increases, so the heart pumps more blood per beat. Increased parasympathetic (vagal) activity can also support a lower resting rate and faster recovery.

As a rough comparison, many untrained people sit around 60–80 beats per minute at rest, while well-trained endurance athletes can be lower (sometimes in the 30s–50s), depending on the person and testing conditions.

Maximum heart rate does not usually increase with training. The main improvement is pumping more blood per beat, not reaching a higher maximum rate.

2.2 Which principles drive it

Heart rate adaptations are strongly linked to specificity (aerobic training stresses the cardiovascular system), training thresholds (intensity must be high enough), progressive overload (the stimulus must increase over time), and reversibility (reduced training allows measures to drift back).

2.3 How performance improves

Lower resting and submaximal heart rates can show improved efficiency. This supports sustained aerobic work with less relative strain, improves recovery between repeated high-intensity efforts in intermittent sports, and helps maintain a higher work rate late in competition.

3. Stroke volume and cardiac output

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

A 1500 m swimmer starts strongly but pace drops through the middle 500m and they cannot hold target splits.
  • Specificity: aerobic conditioning and threshold sets that match 1500 m demands
  • Progressive overload: more weekly aerobic volume and more time at race-relevant intensities
  • Training thresholds: regular work in upper aerobic zones and longer intervals that require high blood flow
  • Higher stroke volume, meaning more blood is pumped per beat
  • Higher maximal cardiac output (Q = SV × HR)
  • Stronger left ventricular filling and ejection
  • Increased blood volume, which improves venous return

Higher sustainable intensity because more oxygenated blood reaches working muscles per minute.

e.g. In a 1500 m swim, mid-race pace is maintained with less drift because aerobic ATP production is supported at higher intensities.

3.1 What changes

Stroke volume is the volume of blood pumped out of the heart with each beat. Cardiac output is the total amount of blood pumped by the heart each minute and is calculated as Q = SV × HR.

With aerobic training, stroke volume can increase due to a stronger left ventricle, better filling between beats, increased blood volume and venous return, and improved ability to eject blood during exercise.

Values vary, but resting stroke volume in untrained individuals may be around 50–70 mL per beat, while trained endurance athletes may be closer to 80–110 mL per beat. During maximal exercise, trained athletes can achieve higher stroke volumes and therefore higher maximal cardiac outputs. Maximal cardiac output is often described as roughly 15–20 L/min in untrained individuals versus around 25–30 L/min in well-trained endurance athletes (body size and training history matter).

At rest, cardiac output is often similar in trained and untrained people because a higher stroke volume is balanced by a lower resting heart rate. During maximal exercise, trained athletes can reach a higher maximal cardiac output mainly because stroke volume is higher.

3.2 Which principles drive it

This adaptation is driven mainly by specificity, progressive overload, and training thresholds. Repeated aerobic workloads challenge the heart’s pumping capacity, overload increases demand over time, and thresholds ensure sessions are hard enough often enough to stimulate change. Variety can help increase training volume while managing overuse, and reversibility explains declines when aerobic training is reduced.

3.3 How performance improves

Higher stroke volume and maximal cardiac output improve performance by increasing oxygen delivery to working muscles. This supports higher aerobic capacity, delays fatigue because aerobic metabolism meets more of the energy demand, and can improve recovery between efforts.

4. Oxygen uptake and lung capacity

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

An 800m runner has excellent speed but “ties up” early, with a clear drop in stride efficiency from 500–700m.
  • Specificity: sessions targeting high aerobic power for 800 m, not just speed
  • Training thresholds: intervals that require high oxygen demand
  • Progressive overload: more reps at pace or slightly shorter recoveries
  • Variety: cross-training to increase aerobic load without excessive impact
  • Higher VO₂ max Improved oxygen delivery through higher cardiac output
  • Improved oxygen extraction in the muscles
  • Increased capillaries, mitochondria and oxidative enzymes
  • Lung volume changes little, but breathing efficiency and sustained ventilation can improve

Higher aerobic work rate under fatigue, delaying severe fatigue.

e.g. In an 800 m, form is held through the third 200 m and the performance drop linked to early anaerobic overload is delayed.

4.1 What changes

Oxygen uptake is the body’s ability to take in oxygen, transport it, and use it in working muscles to produce ATP aerobically. VO₂ max is a common measure of maximal oxygen uptake.

With endurance training, oxygen uptake can improve because cardiac output increases and muscles improve oxygen extraction (for example, through increased capillary density, mitochondria, and oxidative enzymes). Together, these changes improve oxygen delivery and oxygen use.

A common comparison is that sedentary individuals may sit around 30–40 mL/kg/min, trained endurance athletes around 55–70 mL/kg/min, and elite endurance performers higher, depending on the sport and individual.

Lung capacity usually changes little with training in healthy individuals. However, breathing efficiency can improve, including stronger breathing muscles and better ability to sustain high ventilation during intense work. For most students, limits to VO₂ max are more often explained by the heart, blood, and muscles than by lung volume.

4.2 Which principles drive it

Oxygen uptake improvements are linked to specificity, training thresholds, progressive overload, and reversibility. Thresholds ensure the intensity is meaningful, overload extends adaptation over time, and reduced training allows VO₂ max to fall. Variety can support a higher total aerobic load while managing injury risk.

4.3 How performance improves

Improved oxygen uptake increases aerobic ATP production. This raises sustainable intensity before fatigue, supports faster recovery between repeated efforts, and helps athletes maintain technique and decision-making under fatigue.

Example: A Sydney-based 800 m runner improves VO₂ max through interval sessions near the upper aerobic range. In races, the runner holds speed through the third 200 m with less early fatigue, saving anaerobic reserve for the final sprint.

5. Haemoglobin level

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

An elite stage-race cyclist climbs well early but is repeatedly dropped on late-race climbs after hard days, showing poor repeat-day endurance.
  • Specificity: high-volume endurance blocks plus race-relevant climbing intervals
  • Progressive overload: higher weekly load and repeated hard efforts across consecutive days
  • Training thresholds: enough total load and intensity to stimulate red blood cell production
  • Reversibility: maintain aerobic stimulus across the season and avoid long gaps in endurance training
  • Increased total haemoglobin mass
  • Increased red blood cell volume
  • Higher oxygen-carrying capacity
  • Early plasma expansion can temporarily lower measured haemoglobin concentration, even while oxygen transport capacity improves

Better endurance and recovery across repeated hard days.

e.g. On late-stage climbs, higher power is maintained before the same burning fatigue because improved oxygen delivery supports aerobic metabolism.

5.1 What changes

Haemoglobin is the oxygen-binding protein in red blood cells. A higher haemoglobin level (or haemoglobin mass) increases the blood’s oxygen-carrying capacity.

Endurance training can increase total haemoglobin mass and red blood cell production over time. Early in training, plasma volume can increase quickly. This can temporarily lower haemoglobin concentration even while oxygen transport capacity is improving. With continued training, red cell mass may increase, improving oxygen delivery.

Typical haemoglobin concentration ranges vary by sex and other factors. Common reference ranges are around 13–15 g/dL in females and 14–16 g/dL in males. Hydration and iron status can also influence results.

Myoglobin and oxygen transport in muscle

Myoglobin is an oxygen-binding protein inside muscle. It stores oxygen and helps move oxygen to mitochondria. This is often linked to adaptations in slow-twitch fibres and aerobic performance, and helps explain why better oxygen delivery also needs better oxygen use inside muscle.

5.2 Which principles drive it

Haemoglobin-related adaptations are driven mainly by specificity, progressive overload, and training thresholds, with reversibility explaining declines when training is reduced. Dietary iron is also important, because haemoglobin cannot increase if iron availability is low.

5.3 How performance improves

Improved haemoglobin level increases oxygen delivery. This delays reliance on anaerobic metabolism, supports higher sustainable intensity, and can improve recovery between high-intensity bouts.

Example: A junior cyclist completing long weekend rides and mid-week interval sessions improves oxygen delivery capacity. On climbs, the cyclist holds a higher output before the same burning fatigue occurs, because aerobic metabolism contributes more strongly at race pace.

6. Muscle hypertrophy

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

A rugby union prop has strong technique but loses collisions and scrum dominance late in matches and cannot repeat high-force efforts.
  • Specificity: resistance training targeting scrum and collision muscle groups
  • Training thresholds: heavy sets creating high mechanical tension and near-fatigue
  • Progressive overload: heavier loads and/or more weekly volume over time
  • Reversibility: in-season maintenance block to limit strength and size loss
  • Larger muscle fibres
  • Greater muscle fibre cross-sectional area
  • Increased contractile proteins, especially actin and myosin
  • Often greater growth in fast-twitch fibres
  • Higher force-producing capacity

Higher strength and better repeated force production late in matches.

e.g. In rugby union, scrum drive and tackle dominance improve because each effort uses a lower percentage of maximum force capacity.

6.1 What changes

Muscle hypertrophy is an increase in muscle fibre size. It is mainly caused by increases in contractile proteins and muscle fibre cross-sectional area. It is a common adaptation to resistance training and is often more pronounced in fast-twitch fibres.

Hypertrophy occurs when training creates enough mechanical tension and fatigue, followed by recovery, so muscle protein synthesis is greater than breakdown. Some texts describe myofibrillar versus sarcoplasmic hypertrophy, but most training produces a mix rather than a single type.

6.2 Which principles drive it

Hypertrophy is most strongly linked to specificity, progressive overload, and training thresholds. Resistance training must target the right muscles and movements, load and volume must increase over time, and sets must be challenging enough to stimulate growth. Reversibility explains why muscle size can drop if resistance training stops.

6.3 How performance improves

Muscle hypertrophy can improve performance by increasing force potential. This supports greater strength in collision and power sports, improves power when combined with speed and neural training, and can help repeated efforts because a larger muscle can produce the same force with less relative strain.

Example: A rugby union prop completes an off-season strength block with progressive overload in squats, presses, and pulls. Increased muscle hypertrophy improves scrum drive and tackle contact strength, while enough conditioning is maintained to repeat efforts across the match.

7. Fast/slow twitch muscle fibres

Elite athlete

Training principles applied

Physiological adaptation

Improved performance

A football winger has excellent top speed but sprint quality drops late in matches and repeat accelerations become slower and less explosive.
  • Specificity: repeated sprint training plus aerobic conditioning that supports recovery
  • Training thresholds: high intensity to recruit high-threshold Type II motor units, with sufficient aerobic intensity for recovery adaptations
  • Progressive overload: more repeated sprint efforts or reduced rest across weeks
  • Variety: balanced microcycle including speed, strength and aerobic base
  • Type I fibres become more oxidative
  • Increased mitochondria, capillaries and myoglobin in Type I fibres
  • Type II fibres improve explosive capacity
  • Greater hypertrophy, glycolytic enzyme activity and phosphocreatine availability in Type II fibres
  • Type IIa fibres become more fatigue resistant, supporting repeated sprint efforts

Better match between sport demands and output, with stronger late-game sprint capacity.

e.g. In football, acceleration remains sharp in the final 10 minutes because Type II output is maintained and recovery between efforts is faster.

7.1 What changes

Slow-twitch (Type I) fibres are fatigue resistant and suited to aerobic work. Fast-twitch (Type II) fibres produce high force quickly but fatigue faster. Type II fibres are often described in subtypes (for example, IIa and IIx), and training can change how these fibres behave, especially within Type II subtypes.

Fibre proportions are strongly influenced by genetics, but training can improve the functional qualities of each type:

  • endurance training supports slow-twitch characteristics such as more mitochondria, better capillarisation, and higher oxidative enzyme activity
  • sprint and strength training supports fast-twitch characteristics such as higher glycolytic enzyme activity and muscle hypertrophy, helping rapid force production
  • some fast-twitch subtypes can become more fatigue resistant with training, helping repeated sprint ability

7.2 Which principles drive it

Fibre adaptations reflect specificity, training thresholds, progressive overload, and reversibility. Training recruits and develops the fibres most demanded by the work. Higher intensities are needed to recruit high-threshold fast-twitch motor units. Overload builds targeted fibre characteristics over time. Reduced training allows these characteristics to regress.

7.3 How performance improves

Performance improves when fibre qualities match sport demands. Strong slow-twitch function supports endurance, pacing control, and late-race fatigue resistance. Strong fast-twitch function supports speed, power, acceleration, and explosive skill execution. Many team sports need both, because repeated sprints rely on fast-twitch output while recovery between efforts depends heavily on aerobic capacity.

Example: A football winger trains both repeated sprint work and sustained aerobic conditioning. The aerobic base supports late-game running and recovery, while fast-twitch development supports repeated accelerations to beat defenders in the final 10 minutes.

Brief Summary

About the dot point and how to approach it

  • Training for improved performance uses a planned, structured training programme to apply stress so body systems adapt.
  • Examine means show a clear cause-and-effect chain: principles of training → physiological adaptations → improved performance in a specific sport.

1. Principles of training, physiological adaptations and improved performance

  • Applying the principles of training creates predictable physiological adaptations that improve energy production, movement efficiency, force, and fatigue resistance.
  • A strong response links principles used, the adaptations they create, and how these improve sport-specific performance.

2. Heart rate

  • Lower resting heart rate, lower heart rate at the same submaximal workload, and faster recovery.
  • Driven by specificity, training thresholds, progressive overload, and reversibility.
  • Improves sustained work and recovery between repeated efforts, supporting higher work rate late in competition.

3. Stroke volume and cardiac output

  • Higher stroke volume and maximal cardiac output (Q = SV × HR) through aerobic training.
  • Driven mainly by specificity, progressive overload, and training thresholds (with variety and reversibility relevant).
  • Improves oxygen delivery, delaying fatigue and supporting higher sustainable intensity and recovery between efforts.

4. Oxygen uptake and lung capacity

  • Higher VO₂ max mainly through improved oxygen delivery and extraction (more capillaries, mitochondria, oxidative enzymes).
  • Driven by specificity, training thresholds, progressive overload, and reversibility (with variety supporting total aerobic load).
  • Raises aerobic ATP production, improving sustainable intensity, recovery between efforts, and performance under fatigue.

5. Haemoglobin level

  • Increased total haemoglobin mass and red blood cell volume increases oxygen-carrying capacity (plasma expansion can temporarily lower concentration).
  • Driven mainly by specificity, progressive overload, training thresholds, and reversibility (iron availability matters).
  • Improves oxygen delivery, delaying anaerobic reliance and supporting higher sustainable intensity and recovery.

6. Muscle hypertrophy

  • Larger fibres (greater cross-sectional area) with more contractile proteins increases force potential.
  • Driven by specificity, progressive overload, training thresholds, and reversibility.
  • Improves strength and repeated force production because each effort uses a lower percentage of maximum capacity.

7. Fast/slow twitch muscle fibres

  • Type I becomes more oxidative (more mitochondria, capillaries, myoglobin)
  • Type II improves explosive capacity and fatigue resistance for repeated sprints.
  • Driven by specificity, training thresholds, progressive overload, and reversibility.
  • Performance improves when fibre qualities match sport demands (endurance, speed, power, acceleration, repeated sprints).