Energy Systems and Performance

• FQ1: How does training affect performance?

Energy Systems

• Alactacid (ATP/PC) and lactic acid systems are anaerobic, not requiring oxygen for ATP resynthesis.
• The aerobic system depends on oxygen availability for ATP production.
• ATP/PC is used first, followed by lactic acid, and then, if necessary, the aerobic system.

Energy System Factors

• Source of fuel
• Efficiency of ATP production
• Duration the system can operate
• Cause of fatigue
• By-products of energy production
• Process and rate of recovery

ATP/PC

• Fuel source is creatine phosphate.
• Quick and efficient but depletes rapidly.
• Operates for up to 15 seconds.
• Fatigue results from creatine phosphate depletion.
• Produces heat as a by-product.
• PC resynthesis is the recovery process.
• Recovery rate is 2 minutes.

Lactic Acid System

• Fuel source is carbohydrates (glucose in blood, glycogen).
• ATP is rapidly produced and is costly in terms of glucose.
• Operates for 10-60 seconds generally.
  • Near maximal effort leads to exhaustion in 30 seconds.
  • 70-80% effort leads to exhaustion in 3-4 minutes.
  • Moderate intensity can last longer than 3-4 minutes.
• Fatigue results from lactic acid buildup.
• By-product is lactic acid.
• Recovery involves removing lactic acid and replenishing glycogen, taking 30-60 minutes.
• Glycogen or glucose used as fuel is called anaerobic glycolysis, where glucose is broken down without oxygen.

Aerobic System

• Fuel sources are carbohydrates, fats, and proteins.
• Extremely efficient, yielding more energy from glucose.
• Operates for 1-4 hours, depending on individual cardiorespiratory fitness.
• Fatigue can result from glycogen exhaustion, lactic acid buildup, and dehydration.
• By-products are carbon dioxide and water.
• Recovery involves replenishing oxygen stores; the rate depends on the duration of use.

Types of Training and Training Methods

• Aerobic: continuous, Fartlek, aerobic interval, circuit.
• Anaerobic: anaerobic interval.
• Flexibility: static, ballistic, PNF, dynamic.
• Strength: free/fixed weights, elastic, hydraulic.

Training Suitability Assessment

• Consider which training types suit different sports.
• Determine the most appropriate training method(s).
• Assess how training affects performance.

Aerobic Training

• Uses the aerobic system as the primary energy source, following the FITT principle.
  • Frequency: Minimum 3 sessions a week.
  • Intensity: 70-85% of Maximum Heart Rate (MHR).
  • Time: Varies based on intensity, at least 20 minutes.
  • Type: A range of activities.

Continuous Training

• Sustained effort without rests for at least 20 minutes.
• Usually moderate intensity (65-80% max HR).
• Improves the body's efficiency in using oxygen (e.g., swimming, jogging, cycling, running).

Fartlek Training

• Continuous exercise with varied intensity (sprints, hills).
• Involves periods of intense work followed by easier effort.
• Beneficial for sports like Rugby and Soccer.

Aerobic Interval Training

• Alternating exercise reps with short rest/recovery periods to prevent full recovery.
• Applies the overload principle for gains.
• Example: Sprint 40m, then walk back and sprint again.

Circuit Training

• Series of exercises performed sequentially with minimal rest.
• Based on time or repetitions.
• Overload principle is applied.

Anaerobic Training

• "No oxygen"
• High intensity, low duration.
• Maximal effort.
• Rest depends on intensity and duration.

Anaerobic Interval Training

• Develops player's speed or short bursts.
• Increase intensity/duration improves anaerobic threshold and lactic acid tolerance.
• Example: 5 x 100m sprint with 2-3 minutes recovery between each.

Flexibility Training

• Aim: Increase range of motion at a joint.
• Benefits:
  • Injury prevention
  • Higher skill level.
  • Enhanced muscle coordination.
  • Improved muscle stretch ability.
  • Reduced muscle tightening.
  • Muscle relaxation and recovery.

Static Stretching

• Gradual muscle lengthening held for 10-30 seconds
• Good for rehab.

Dynamic Stretching

• Rhythmical movements of major muscle groups used in the activity (e.g., lunges).

Ballistic Stretching

• "Bouncing action" at the end of the Range of Motion (ROM) to activate stretch reflex.
• Dangerous, used for elite athletes.

Proprioceptive Neuromuscular Facilitation (PNF) Stretching

• Lengthening muscle action against resistance.
• Sequence: Static → isometric → rest → repeat.

Strength Training

• Resistance applied to a muscle to contract.
  • Involves:
    • ISOTONIC (shortens/lengthens).
    • ISOMETRIC (no change).
    • ISOKINETIC (constant load).
• Resistance can be achieved via:
  • Body weight.
  • Barbells/dumbbells.
  • Weight machines.
  • Hyraulic resistance machines
  • Elastic bands.
  • Water aerobics.

Free Weights

• Provides wide range of exercises for all muscle groups
• Examples: Dumbbells, barbells, plates.

Fixed Weights

• Common and mainly isotonic.
• Simple and safe (machines, smith machine).

Elastic Resistance

• Convenient for warm-ups and rehabilitation, offering a range of contractions.

Hydraulic Resistance

• Provides constant resistance.
• Expensive equipment found in physio settings.

Training Type: Fartlek for Basketball

• Players run at varying intensities on the court.
• Recruits both fast- and slow-twitch muscle fibers.
• Enables sprinting and continuous effort, as needed.

Training Type: Continuous for Triathlon

• Continuous swimming, cycling, and running.
• Recruits slow-twitch muscle fibers
• Enables extended activity.

Soccer Training

• Positions like center midfield require continuous running.
• Stricker and winger positions involve sprinting.
• Combines both aerobic training types to recruit fast and slow-twitch muscle fibres.

Example: High Jump Training

• Includes interval training to build up fast-twitch muscle fibres
• Resistance training of the legs for power.

Surfing Training

• Involves continuous isometric contraction of the hamstrings to remain balanced.
• Isometric resistance training is beneficial.

Example: 100m Hurdles Training

• Includes interval training to recruit fast-twitch muscle fibres
• Isotonic resistance training program for the legs. Moderate to high loads, 60–80 percent of 1 RM.

Rugby Training

• Interspersed periods of effort and sprint.
• Benefit from Fartlek training.
• Benefit mainly from Fartlek training to recruit both fast- and slow-twitch muscle fibres.

Principles of Training

• Progressive overload.
• Specificity.
• Reversibility.
• Variety.
• Training thresholds.
• Warm up and cool down.

Progressive Overload Explained

• Training effect achieved when system/tissue works harder than accustomed.
• How to increase:
  • Intensity.
  • Resistance/loads/reps.
  • Duration.
  • Frequency.
• Increases the hearts ability to pump more blood to the working muscles
• Increases the ability of the working muscles to take up more of the oxygen as it is delivered to the cells (Increased oxygen uptake)
• Increase the cross sectional area of the muscle

Specificity Principle

• Greatest gains when training replicates game/activity movements.
• Specific for energy systems, muscles, and fitness components.
• Exercise should be specific for the energy pathway at least 95% of the time.
• Activities should recruit slow-twitch muscle fibres so enzymes become more efficient in the muscle fibre.
• For marathon runners, they should ensure the third energy pathway uses 95 per cent or more of the time.
• For a sprinter, correctly address the speed and number of repetitions, load and time so that improvements are made to muscle bulk.

Variety Principle

• Strength training uses a variety of methods like Isometric and isotonic methods
• Aerobic training takes many forms -> swimming, running, cycling and circuit training.

Reversibility Principle

• Principal of training states what effects of training are reversible.
• Gains made in fitness are lost gradually if training ceases.
• Ability of working muscles is reduced when training stops.
• With strength/power the programs are faster as minimal stimulation is necessary.

Training Threshold Principle

• The body needs to improve its ability to use oxygen through exercise.
• Intensity is the body's maximum (speed/power/effort)
• Accelerates glycolysis (conversion of glucose to glycogen and glycogen to pyruvic acid)
• This often increases fast twitch muscles.
• Often at 75 - 80% of VO2 max
• Often this occurs at 70% of max HR.

Warm Up/Warm Down Training

• Warms up involve getting the body ready for training activity.
  • Increases blood flow to working muscles
  • Increases body temperature making the muscles, ligaments, and tendons more elastic.
  • Extra elasticity reduces the likelihood of injury.
• Cool downs are effective as warm ups but in reverse:
  • Allows for active recovery.
  • Allows oxygenated blood to flush out waste products formed during activity.
  • Should incorporate a session of stretching.
  • Includes aerobic exercises as the intensity is reduced.
  • Stretching is done for 50 -60% of VO2 max

Physiological Adaptations

• Include:
  • Resting heart rate.
  • Stroke volume and cardiac output.
  • Haemoglobin level.
  • Muscular hypertrophy.
  • Effect on fast/slow twitch muscle fibres.

Resting Heart Rate & Training

• Resting HR falls as the program increases SV.
• Requires fewer beats to deliver the same oxygen amount.

Stroke Volume & Training

• Training causes the left ventricle to fill during diastole.
• More blood enters the ventricle due to increase in blood plasma.

Cardiac Output & Training

• Both heart rate and stroke volume increase.

Oxygen Uptake & Training

• VO2 max increases oxidative enzymes.