Inquiry question 1 Flashcards
Stretch Reflex
The muscles automatically protect themselves from injury by counteracting the stretch. Muscles have inside sensors that can tell how far they’ve been stretched. If a sensor feels too much tension, it will send a signal to the muscle to pull back to prevent the joint from injury.
Dynamic Stretching
- AKA Active stretching
- Stretches muscles that cross over joints
- Athlete performs movements that take their joints through the full ROM to produce temporal stretches of selected muscles
- Joint mobility improves
Stimulates Cardiovascular system - Sport specific movements
Avoids muscle micro tears
PNF Stretching
Proprioceptive neuromuscular facilitation
Most effective from of stretching based on 2 principles:
1. Muscles relax better after they’ve undergone a max isometric contractions its resistance to stretching is reduced
2. A muscle becomes stronger if its antagonist is isometrically contracted immediately before hand
Method:
1. Muscle is stretched with a static contraction
2. While stretching, person isometrically contracts
3. Person relaxes in lengthened position
4. Recovery before repeating
Isotonic
Muscle develops tension and either lengthens or shortens, there is a change in fibre length and movement of the joint
Concentric
Fibres shorten and joint angle decreases
Eccentric
Fibres lengthen and joint angle increases
Isometric
Muscle fibres develop tension but there is no movement
Isokinetic
Hydraulic
Resistance varies –> both push and pull
Harder you push = more resistance
Both antagonist and agonist pair are working
Strength training
- Increases strength
- Causes muscular hypertrophy
- Large stress on muscle causes minor tears which the body responds to by increasing the muscles so next time there won’t be as much damage
- Fundamental to most sport
- Uses reps, sets
- Requires: appropriate resistance, progressive overload, recovery
Types of strength
Absolute strength: max force that can be exerted
Relative strength: Max strength relative to weight
Muscular endurance: Ability of a muscle group to withstand fatigue
Power: Speed x Strength –> ability to apply force at a rapid rate
Elastic resistance training
performed against the natural resistance of elastic. As band stretches resistance increases
Free/ fixed weights
Lifting a certain weight against gravity
Free weights develop stabilising muscles but poor form can lead to injury
Fixed weights utilise machines to lift which helps athletes learn correct from and experience equal resistance through the full range of motion
ATP
Adenosine Triphosphate
The only source of energy in our bodies for biological work
Captures chemical energy obtained from the breakdown of food molecules and releases it to fuel other cellular processes
ATP-PC system
Fuel: creatine phosphate
Duration: High intensity, short duration
Efficiency: ATP resynthesises quickly but limited ATP is produced
Fatigue: CP and ATP runs out
By products: Heat
Recovery: 50% 30 secs, 100% in 2-3 min
Nutrients (energy source)
Each of the energy systems have a fuel source which is broken down to provide energy to resynthesize ATP. Fuel comes from food we eat
Carbohydrates -> Glucose
Fats -> Glycerol
Proteins -> amino acids
Energy
‘The ability to do work’
Energy transforms from chemical to mechanical
For Metabolism and Movement
ATP-PC Pathway
- Uses ATP stored in muscles (2-3 secs worth)
- Uses creatine phosphate to recycle ATP until CP runs out
CP splits releasing energy held in bonds
This energy is used to drive any free phosphate molecules back onto ADP therefore resynthesising ATP
Amount of ATP produced for each system
ATP-PC: 1
Lactic Acid: 2
Aerobic: 34 –> actually resynthesises more but these are used up in the Crebs cycle and electron transfer reaction which are used to strip the energy from fossil fuels
Aerobic system ATP resynthesis
- Fats used at low intensity
- Proportion of carbs increase with increasing intensity
- Proteins can be used if the body uses up it stores of carbs an fats but only in extremes
- In them presence of sufficient O2, all 3 fuels can be completely broken down releasing plentiful energy for ATP resynthesis with the non-fatiguing by produces H20 and CO2
Aerobic System
More sustained and plentiful supply of energy
Fuel: Carbs, fats, protiens
Duration: Hours as long as there is fuel
Efficiency: Slower to kick in
Fatigue: Running out of fuel
By Products: Heat, Co2, H2O
Recovery: Replace fuels –> up to 48 hours
Lactic Acid System
Fuel: Glucose
Duration: 10 sec-3min
Efficiency: Fast resynthesis but limited supply
By Products: Heat, Lactate, Hydrogen ions
Fatigue: Accumulation of Hydrogen ions and pyruvic acid
Recovery: Low intensity movement to allow O2 to return to blood, 45 min -2hr
Lactic Acid System ATP resynthesis
- In the absence of O2 the glucose is partly broken down to pyruvate. The energy released is used to resynthesise a small amount of ATP
- This breakdown causes hydrogen ions to be released causing muscles to become acidic. To reduce the ions, the body produces lactate
- Fatigue is due to the increase in hydrogen ions not the concentration of lactic acid