Project 2 Topic 2 Chronic Adaptations to Training

Adaptations occur in: Muscular System Skeletal System Cardiovascular System Respiratory System Energy Systems Aerobic Anaerobic

Chronic Adaptations To initiate adaptations to the body systems training must: Training should “overload” the system that the individual wishes to train! Work above and beyond what the system is accustomed to and it will adapt Training should be specific to achieve the desired adaptations Training has been occurring for a minimum of 6-8 weeks, training at least 3 sessions per week.

Muscular System Hypertrophy & Hyperplasia Capillaries Mitochondria Myoglobin Stores Tolerance to Lactic Acid Storage of Glycogen & Fat Skeletal System Strength & stretch of connective tissue (tendons & ligaments) Bone density Hyaline cartilage Synovial fluid Cardiovascular System Cardiac Hypertrophy Stroke Volume Cardiac Output Blood Volume Resting Heart Rate Resting Blood Pressure Recovery Time Respiratory System Strength of Respiratory Muscles Vital Capacity 1 Minute Ventilation O² Diffusion Rate Energy Systems -Aerobic ATP & CP Lactic Acid System (Anaerobic Glycolysis) -Anaerobic Activity of oxidative enzymes Fuel sources (fats & glucose)

Fast Twitch (Type II) WHITE MUSCLE FIBERS: WHITE MUSCLE FIBERS: -large in diameter -light in colour (low myoglobin) -surrounded by few capillaries -relatively few mitochondria -high glycogen content (they have a ready supply of glucose for glycolysis) -  anaerobic capacity –Fatigue easily –Fast contractile velocity Anaerobic exercise Anaerobic exercise (sprinting, weight- lifting) – short duration, great intensity (fast-twitch muscle fibers); creatine phosphate + glycogen (glucose) from muscle Slow Twitch (Type I) RED MUSCLE FIBERS RED MUSCLE FIBERS: -red in colour (high myoglobin content) -surrounded by many capillaries -numerous mitochondria -low glycogen content (they also metabolize fatty acids and proteins, which are broken down into the acetyl CoA that enters the Krebs cycle) Recap on the Muscles Aerobic exercise Aerobic exercise (long-distance running, swimming)- prolonged but at lower intensity (slow-twitch mucle fibers) fuels stored in muscle, adipose tissue and liver

Hypertrophy & Hyperplasia Increase in Size: Hypertrophy (Particularly Type II) Increase in Number: Hyperplasia ↑ No. of Capillaries Increase in number enables greater delivery of O² rich blood ↑ No. of Mitochondria Increase in number allows more aerobic energy to be produced ↑ Myoglobin Stores Increase in number allows more storage and supply of O 2 to the muscle cells ↑ Tolerance to Lactic Acid you produce the same amount of Lactic Acid however the body can withstand higher levels ↑ Storage of Glycogen & Fat this creates a more readily available supply of energy Muscular Adaptations

Skeletal Adaptations  in strength & stretch of connective tissue (tendons & ligaments) Ligament / Tendon Strength and stretch Increases due to an increase in collagen and due to small amounts of damage that occur during exercise increase release of molecules that promote repair and re-growth Increase in connective tissue surrounding muscle fibers  Increased bulk  Bone Density (thicker and stronger) due to  in bone calcium and mineral stores as a result of compensating for increased workloads  thickness of hyaline cartilage Stimulated by increased workload, creates more protection  production of synovial fluid Stimulated by increased workload, creates more efficient movement and protection

Cardiovascular Adaptations Cardiac Hypertrophy enlargement of the heart muscle. Heart chambers are enlarged which increases ventricular volume (most important is Left Vent. size – why?) ↑ Stroke Volume (vol. of blood pumped per beat) SV increases at REST, during sub max & max workloads. ↑ Cardiac Output (Q) (Q= SV x HR amount of blood leaving the heart in 1 min) Increases due to bigger heart and bigger volume. Q remains unchanged at rest and even during sub max. work regardless of how hard you train. During max. exercise Q may increase up to 30 litres per minute for highly trained athletes ↑ Blood Volume Effect of aerobic training, can be up to 25%. Results in no. of RBC increase, therefore haemoglobin increases thus O2 carrying capacity increases also. ↓ Resting Heart Rate Because the athlete has greater stroke volume the heart does not need to beat as often to pump the same amount of blood around the body. Resting Heart Rate below 60bpm is termed bradycardia. ↓Resting Blood Pressure Both systolic and diastolic blood pressure levels may decrease during REST and EXERCISE. Less/slower beats reduce blood vessel resistance to blood flow and reduces strain on the heart. ↓Recovery Time The heart rate of an athlete will return to normal (pre exercise levels) quicker than an untrained person. ↑ overall aerobic fitness

Respiratory Adaptations ↑ Strength of Respiratory Muscles increased strength of respiratory muscles such as: Diaphragm Inter costal musclesRhomboids Sternocleidomastoid This will further expand the thoracic cavity creating a bigger volume (= more O²) ↑ Vital Capacity As a result of increased number of alveoli activated & capillarisation around those alveoli ↑ 1 Minute Ventilation the total volume of gas entering the lungs per minute. ↑ O² Diffusion Rate This is due to capillarisation around the alveoli. Over all = Increased Maximum Oxygen Uptake (VO 2 MAX ) (Aerobic Fitness) Between %. Due to: increased muscle and alveoli capillarisation increased gaseous exchange greater oxygen extraction by muscles

Energy Systems Anaerobic (without oxygen) ATP & CP – Will increase stores of ATP & CP Lactic Acid System (Anaerobic Glycolysis) –  in levels of glycolytic enzymes – Less Lactic Acid produced – Increased buffering capacity more able to tolerate lactic acid for longer – More energy can be produced through these systems

Energy Systems Aerobic (with Oxygen) ↑ activity of oxidative enzymes ↑ increased capacity to oxidize Fats shifts the energy source from glucose to fat (to spare glucose)

What do these adaptations mean? More availability of oxygen More efficiency in utilising oxygen Better tolerance to lactic acid Increased fatigue resistance Overall; Increased aerobic fitness levels (better VO2max) Increased aerobic fitness levels (better VO2max)