Adaptationstoaerobictraining.ppt
- 2. Adaptations to aerobic training Cardiorespiratory endurance Endurance training Major Cardiovascular Changes Respiratory Changes Muscle Changes Metabolic Changes
- 3. Cardiorespiratory endurance ◦ Ability to sustain prolonged, dynamic exercise ◦ Improvements achieved through multisystem adaptations (cardiovascular, respiratory, muscle, metabolic) Endurance training – Maximal endurance capacity = VO2max – Submaximal endurance capacity Lower HR at same submaximal exercise intensity More related to competitive endurance performance
- 5. Heart size Stroke volume Heart rate Cardiac output Blood flow Blood pressure Blood volume
- 6. O2 transport system and Fick equation ◦ VO2 = SV x HR x (a-v)O2 difference – VO2max = max SV x max HR x max (a-v)O2 difference Heart size ◦ With training, heart mass and LV volume – Target pulse rate (TPR) cardiac hypertrophy SV – Plasma volume LV volume EDV SV ◦ Volume loading effect
- 8. SV after training ◦ Resting, submaximal, and maximal ◦ Plasma volume with training EDV preload ◦ Resting and submaximal HR with training filling time EDV – LV mass with training force of contraction ◦ Attenuated TPR with training afterload SV adaptations to training with age
- 11. Resting HR – Markedly (~1 beat/min per week of training) – Parasympathetic, sympathetic activity in heart Submaximal HR – HR for same given absolute intensity ◦ More noticeable at higher submaximal intensities Maximal HR ◦ No significant change with training – With age
- 13. HR-SV interactions ◦ Does HR SV? Does SV HR? ◦ HR, SV interact to optimize cardiac output HR recovery ◦ Faster recovery with training ◦ Indirect index of cardiorespiratory fitness Cardiac output (Q) ◦ Training creates little to no change at rest, submaximal exercise ◦ Maximal Q considerably (due to SV)
- 16. • Blood flow to active muscle • Capillarization, capillary recruitment – Capillary:fiber ratio – Total cross-sectional area for capillary exchange • Blood flow to inactive regions • Total blood volume ◦ Prevents any decrease in venous return as a result of more blood in capillaries
- 18. Blood pressure – BP at given submaximal intensity – Systolic BP, diastolic BP at maximal intensity Blood volume: total volume rapidly – Plasma volume via plasma proteins, water and Na+ retention (all in first 2 weeks) – Red blood cell volume (though hematocrit may ) – Plasma viscosity
- 21. Pulmonary ventilation – At given submaximal intensity – At maximal intensity due to tidal volume and respiratory frequency Pulmonary diffusion ◦ Unchanged during rest and at submaximal intensity – At maximal intensity due to lung perfusion Arterial-venous O2 difference – Due to O2 extraction and active muscle blood flow – O2 extraction due to oxidative capacity
- 22. Fiber type – Size and number of type I fibers (type II type I) ◦ Type IIx may perform more like type IIa Capillary supply – Number of capillaries supplying each fiber ◦ May be key factor in VO2max Myoglobin – Myoglobin content by 75 to 80% ◦ Supports oxidative capacity in muscle
- 23. Mitochondrial function – Size and number ◦ Magnitude of change depends on training volume Oxidative enzymes (SDH, citrate synthase) – Activity with training ◦ Continue to increase even after VO2max plateaus ◦ Enhanced glycogen sparing
- 26. High-intensity interval training (HIT): time- efficient way to induce many adaptations normally associated with endurance training Mitochondrial enzyme cytochrome oxidase (COX) same after HIT versus traditional moderate-intensity endurance training
- 28. Lactate threshold – To higher percent of VO2max – Lactate production, lactate clearance ◦ Allows higher intensity without lactate accumulation Respiratory exchange ratio (RER) – At both absolute and relative submaximal intensities – Dependent on fat, dependent on glucose
- 30. Resting and submaximal VO2 ◦ Resting VO2 unchanged with training ◦ Submaximal VO2 unchanged or slightly with training Maximal VO2 (VO2max) ◦ Best indicator of cardiorespiratory fitness – Substantially with training (15-20%) – Due to cardiac output and capillary density
- 33. Long-term improvement ◦ Highest possible VO2max achieved after 12 to 18 months ◦ Performance continues to after VO2max plateaus because lactate threshold continues to with training Individual responses dictated by ◦ Training status and pretraining VO2max ◦ Heredity
- 35. Training status and pretraining VO2max ◦ Relative improvement depends on fitness ◦ The more sedentary the individual, the greater the ◦ The more fit the individual, the smaller the Heredity ◦ Finite VO2max range determined by genetics, training alters VO2max within that range ◦ Identical twin’s VO2max more similar than fraternal’s ◦ Accounts for 25 to 50% of variance in VO2max
- 37. Sex ◦ Untrained female VO2max < untrained male VO2max ◦ Trained female VO2max closer to male VO2max High versus low responders ◦ Genetically determined variation in VO2max for same training stimulus and compliance ◦ Accounts for tremendous variation in training outcomes for given training conditions
- 40. Endurance training critical for endurance-based events Endurance training important for non- endurance-based sports, too All athletes benefit from maximizing cardiorespiratory endurance