Aerobic and anaerobic

effect of aerobic and anaerobic exercises

1. Training the Anaerobic and Aerobic Energy Systems Dr. AMRIT KAUR Professor , MVP college of physiotherapy

2. Aerobic respiration During aerobic respiration your heart and lungs work to supply the muscles with oxygen. The aerobic system is used in moderate to hard continuous activities. The formula for aerobic respiration is: glucose + oxygen = Energy + CO2 + H2O To help you remember: Extra air = aerobic respiration

3. As long as enough oxygen is supplied to the muscles you can use the aerobic system.

4. Anaerobic respiration glucose + NO oxygen lactic acid + energy During anaerobic respiration the muscles are NOT supplied with oxygen. To help you remember: No air = anaerobic respiration

5. Athletic field events are good examples of anaerobic exercise. These activities use one all-out burst of maximum effort to complete the event; the time it takes to complete the attempt is very short.

6. The demand for oxygen is so great that the cardiovascular system does not have time to supply the demand. When an athlete stops after a sprint, they continue to breathe more heavily for a while to take in ‘extra’ oxygen. This is in order to break down the accumulated lactic acid, which makes your muscles feel tired. The shortage of oxygen is called oxygen debt , and the body is paying back the oxygen built up during the sprint.

7. GENERAL TRAINING PRINCIPLES Overload Principle Specificity Principle Individual Differences Principle Reversibility Principle

8. ADAPTATIONS TO EXERCISE TRAINING Anaerobic System Changes Increased levels of anaerobic substrates - increases in the trained muscle’s resting levels of ATP, PCr , free creatine , and glycogen, accompanied by an improvement in muscular strength . Increased quantity and activity of key enzymes that control the anaerobic phase of glucose catabolism- The most dramatic increases in anaerobic enzyme function and fiber size occur in fast-twitch muscle fibers . The changes do not reach the magnitude observed for oxidative enzymes with aerobic training.

9. Increased capacity to generate high levels of blood lactate during all-out exercise . Enhanced lactate producing capacity probably results from a training-induced increased levels of glycogen and glycolytic enzymes and improved motivation and “pain ” tolerance to fatiguing exercise.

10. Aerobic System Changes- Metabolic Adaptations Metabolic Machinery An increase in mitochondrial size and number in aerobically trained skeletal muscle improves its capacity to generate ATP by oxidative phosphorylation. Enzymes A twofold increase in the level of aerobic system enzymes complements the increase in mitochondrial size and number and coincides with increased mitochondrial capacity to generate ATP. These adaptations likely allow the trained person to sustain a high percentage of aerobic capacity during prolonged exercise without accumulating blood lactate

11. Fat Catabolism Regular aerobic exercise profoundly improves ability to oxidize fatty acids, particularly triacylglycerols stored within active muscle during steady-rate exercise. Lipolysis increases from greater blood flow within trained muscle and a higher quantity of fat-mobilizing enzymes from adipocytes and fat-metabolizing within muscle fibre's enzymes . This allows endurance athlete to exercise at a higher absolute level of submaximal exercise before experiencing the fatiguing effects of glycogen depletion compared with an untrained person.

12. Carbohydrate Catabolism- Aerobically trained muscle exhibits an enhanced capacity to oxidize carbohydrate . A trained muscle’s greater mitochondrial oxidative capacity and increased glycogen storage contribute to the enhanced capacity for carbohydrate breakdown. Increased carbohydrate catabolism during intense aerobic exercise serves two important functions: 1. Provides a considerably faster aerobic energy transfer than from fat breakdown 2. Liberates about 6% more energy than fat per quantity of oxygen consumed

13. Muscle Fiber Type and Size- Highly trained endurance athletes have larger slow- than fast-twitch fiber in the same muscle. Conversely, for athletes trained in anaerobic-power activities, fast-twitch fibers occupy more of the muscles’ cross-sectional area.

14. Cardiovascular Adaptations Heart Size- Long-term aerobic training generally increases the heart’s mass and volume with greater left ventricular enddiastolic volumes during rest and exercise. This enlargement, characterized by increased size of the left ventricular cavity (eccentric hypertrophy) and modest thickening of its walls (concentric hypertrophy), improves the heart’s stroke volume . Plasma Volume - Only four training sessions increase plasma volume up to 20%. This adaptation enhances circulatory and thermoregulatory dynamics and facilitates oxygen delivery to muscle during exercise. The rapid increase in plasma volume with aerobic training also contributes to training induced eccentric hypertrophy with concomitant increases in stroke volume.

15. Stroke Volume- An endurance athlete’s heart has a considerably larger stroke volume at rest and during exercise than an untrained person of similar age . Heart Rate- decrease HR at rest . A linear relationship between heart rate and oxygen uptake exists for both groups throughout the major portion of the exercise range. As exercise intensity increases, the heart rates of the athletes accelerate to a lesser extent than untrained adults;

16. Oxygen Extraction- Aerobic training increases the maximum quantity of oxygen extracted from arterial blood during exercise . Blood Flow and Distribution- Three factors explain why aerobic training causes large increases in muscle blood flow during maximal exercise: 1. Improvements in maximum cardiac output 2. Redistribution (shunting) of blood from non-active areas 3. Increased capillarization within the trained muscle tissues

17. Blood Pressure- Aerobic exercise training decreases systolic and diastolic blood pressures during rest and submaximal exercise . A training-induced reduction in sympathetic nervous system hormones ( catecholamines ) contributes to the lowering effect of regular exercise on blood pressure, perhaps via a reduction in peripheral vascular resistance to blood flow . Exercise training also facilitates the kidneys’ elimination of sodium, which subsequently reduces fluid volume and blood pressure

18. Pulmonary Adaptations Maximal Exercise- Improvements in maximal oxygen uptake with training increase maximal exercise minute ventilation . This adaptation makes sense physiologically because improved aerobic capacity reflects larger oxygen utilization and the need to eliminate greater quantities of carbon dioxide by increased alveolar ventilation .

19. Submaximal Exercise- Exercise training improves the ability to sustain high levels of submaximal ventilation. For example , 20 weeks of regular run training increased the endurance of ventilatory muscles by 16% in healthy adult men and women. Less lactate accumulated during submaximal breathing exercise, probably from the increase in aerobic enzyme levels in the ventilatory musculature. Enhanced ventilatory endurance reduces the feeling of breathlessness and pulmonary discomfort frequently experienced by untrained persons who perform prolonged submaximal exercise

20. The precise mechanism for the reduced ventilatory equivalent during submaximal exercise after training remains unresolved In general, tidal volume increases, breathing frequency decreases, and air remains in the lungs for a longer time interval between breaths. Slower breathing increases the amount of oxygen the alveoli extracts from the inspired air volume.

21. Blood Lactate Concentration- effect of endurance training in lowering blood lactate levels and extending exercise duration before onset of blood lactate accumulation (OBLA) during exercise of increasing intensity. The explanation underlying this effect centers on three possibilities related to central and peripheral adaptations to training 1 . Decreased rate of lactate formation during exercise 2. Increased rate of lactate clearance (removal) during exercise 3. Combined effects of decreased lactate clearance and increased lactate removal

22. Body Composition Changes- For overfat or borderline overfat people, regular aerobic exercise reduces body mass and body fat. Increases in fatfree body mass also accompany a regular program of resistance training. Exercise only, or exercise combined with calorie restriction, reduces body fat more than fat lost with only dieting because exercise conserves the body’s lean tissue mass.

23. Temperature Regulation Well-hydrated, aerobically trained individuals exercise more comfortably in hot environments because of a larger plasma volume and more-responsive thermoregulatory mechanisms . Trained men and women dissipate heat faster and more effectively than untrained persons

24. Psychologic Benefits Regular exercise, either aerobic or resistance training produces psychologic benefits regardless of age.

25. FACTORS AFFECTING THE AEROBIC TRAINING RESPONSE Initial Level of Cardiorespiratory Fitness Training Frequency- In general , a training response occurs with exercise performed at least three times weekly for at least 6 weeks . Training Duration Training Intensity Genes

26. FORMULATING AN AEROBIC TRAINING PROGRAM General Guidelines Start slowly . Allow a warm-up period Allow a cool-down period

27. METHODS OF TRAINING Anaerobic Training The Intramuscular High-Energy Phosphates- Engaging specific muscles in repeated 5- to 10-secon maximum bursts of effort overloads the phosphagen pool. The intramuscular high-energy phosphates supply energy for intense but brief exercise, so little lactate accumulates, and recovery progresses rapidly. Thus , exercise can begin again after about a 30-second rest. Brief, all-out exercise interspersed with recovery represents a specific application of interval training for anaerobic conditioning.

28. The activities selected to enhance ATP– PCr energy transfer capacity must engage the specific muscles at the movement speed and power output for which the athlete desires improved anaerobic power ( specificity principl ). Lactate-Generating Capacity- As the duration of maximal effort extends beyond 10 seconds, dependence on anaerobic energy from the intramuscular high-energy phosphates decreases , with a proportionate increase in anaerobic energy transfer from anaerobic glycolysis . To improve energy transfer capacity by the short-term lactic acid energy system, training must overload this aspect of energy metabolism.

29. Repeated bouts of up to 1-minute maximum exercise stopped 30 seconds before subjective feelings of exhaustion cause blood lactate to increase to near-maximum levels. The individual repeats each exercise bout after 3 to 5 minutes of recovery. Repetition of exercise causes “lactate stacking ,” which results in a higher blood lactate level than with just one bout of exhaustive effort. As with all training regimens , one must exercise the specific muscle group that require enhanced lactate-producing capacity

30. Aerobic Training Continuous Training Continuous long slow distance ( LSD ) training requires sustained, steady-rate aerobic exercise.Because of its submaximal nature, exercise continues for considerable time in relative comfort. This makes LSD training ideal for people beginning an exercise program or wanting to enhance calorie burning to reduce excess body fat.

31. Interval Training- Interval exercise training simulates this variation in energy transfer intensity through specific spacing of exercise and rest periods . continuously. Rest-to-exercise intervals vary from a few seconds to several minutes depending on the energy system(s) overloaded. Four factors formulate the interval training prescription: 1. Intensity of exercise interval 2. Duration of exercise interval 3. Duration of recovery interval 4. Repetitions of exercise-recovery interval

32. Fartlek Training- Fartlek training workouts do not require systematic manipulation of exercise and relief intervals in contrast to the precise exercise-interval training prescription. In fartlek , the performer determines the training schema based on “how it feels” at the time, in a way similar to gauging exercise intensity based on one’s rating of perceived exertion . If used properly, this method will overload one or all of the energy systems. Fartlek training provides an ideal means of general conditioning and off-season training , but it lacks the systematic quantified approache of interval and continuous training.