Aerobic Exercise Product
Aerobics For Fitness
Getting in shape and staying fit is not always easy but some ways are easier than others such as aerobics when you do it right. Aerobics For Fitness Provides You With Everything You Need to Know to Make Aerobics Work Right And Produce Real Fitness Results.
Those muscles adapted for mostly aerobic metabolism contain significant amounts of the protein myoglobin. This iron-containing molecule, essentially a monomeric form of the blood protein hemoglobin (see Chapter 11), gives aerobic muscles their characteristic red color. The total oxygen storage capacity of myoglobin is quite low, and it does not make a significant direct contribution to the cellular stores,- all the myoglobin-bound oxygen could support aerobic exercise for less than 1 second. However, because of its high affinity for oxygen even at low concentrations, myoglobin plays a major role in facilitating the diffusion of oxygen through exercising muscle tissue by binding and releasing oxygen molecules as they move down their concentration gradient.
The exact mechanism responsible for the development of collateral vessels is unknown. However, periods of inadequate blood flow to the heart muscle caused by experimental flow reduction do stimulate collateral enlargement in healthy animals. It is assumed that in humans with coronary vascular disease who develop functional collateral vessels, the mechanism is related to occasional or even sustained periods of inadequate blood flow. Whether or not routine exercise aids in the development of collaterals in healthy humans is debatable the benefits of exercise may be by other mechanisms, such as enlargement of the primary perfusion vessels and the reduction of atherosclerosis. However, there is no doubt that frequent and relatively intense aerobic exercise is beneficial to cardiac vascular function.
Skeletal muscle blood flow can increase 10- to 20-fold or more during the maximal vasodilation associated with high-performance aerobic exercise. Comparable increases in metabolic rate occur. Under such circumstances, total muscle blood flow may be equal to three or more times the resting cardiac output obviously, cardiac output must increase during exercise to maintain the normal to increased arterial pressure (see Chapter 30).
During fasting, suppressed after meals, and stimulated to very high levels during aerobic exercise for triacylglycerol-fatty acids it is roughly the converse. This requires co-ordination between metabolic pathways in different organs, in relation both to the influx of dietary lipids and the body's requirement for lipids. In Chapters 4 and 5 we have seen how this co-ordination can be brought about by hormones, and in particular by insulin whose secretion from the pancreas is stimulated in the 'fed7 state. Insulin acts both by affecting the activity of enzymes on a short-term basis (e.g. by reversible phosphorylation dephosphorylation) and on a longer term basis by regulation of gene expression. However, the main stimulus for insulin secretion is a rise in the plasma glucose concentration. It would seem sensible that the body should also have means for homeostasis of lipid metabolism that do not depend upon the simultaneous ingestion of carbohydrate in appropriate amounts.
For example, Peter Glick and his colleagues (1988) masculinized'the fictitious resumes of female and male applicants by giving them summer jobs in a sports store (as opposed to a feminine jewelry store), a work-study job in grounds maintenance (vs. aerobics instructor), and captain of the varsity basketball team (vs. pep squad). They found that masculinizing information about female candidates for a position in sales management in a heavy machinery company enhanced their likelihood of being interviewed, although being male was an even stronger predictor (also see Branscombe & Smith, 1990). In general, candidates who seem to mesh with the gender orientation of a job are considered stronger applicants (Towson, Zanna, & MacDonald, 1989). Sometimes giving the impression of a good fit simply requires some semantic reframing. For example, my husband advised a woman graduate student to list her hobby truthfully as a marathoner, not a jogger, when she applied for a masculine-typed position.
Whether exercise is light, moderate, or heavy for a given person depends on that person's maximal capacity for aerobic exercise. The maximum rate of oxygen consumption (by aerobic respiration) in the body is called the maximal oxygen uptake, or the aero.bic capacity, and is often expressed in abbreviated form as the VO2 max. The maximal oxygen uptake is determined primarily by a person's age, size, and sex. It is from 15 to 20 higher for males than for females and highest at age 20 for both sexes. The VO2 max ranges from about 12 ml of O2 per minute per kilogram body weight for older, sedentary people to about 84 ml per minute per kilogram for young, elite male athletes. Some world-class athletes have maximal oxygen uptakes that are twice the average for their age and sex this appears to be due largely to genetic factors, but training can increase the maximum oxygen uptake by about 20 .
The Regulation of Muscle Blood Flow Depends on Many Mechanisms to Provide Oxygen for Muscular Contractions
During rhythmic muscle contractions, the blood flow during the relaxation phase can be high, and it is unlikely that the muscle becomes significantly hypoxic during submaximal aerobic exercise. Studies in humans and animals indicate that lactic acid formation, an indication of hypoxia and anaerobic metabolism, is present only during the first several minutes of submaximal exercise. Once the vasodila-tion and increased blood flow associated with exercise are established, after 1 to 2 minutes, the microvasculature is probably capable of maintaining ample oxygen for most workloads, perhaps up to 75 to 80 of maximum perform
There is now good evidence from large-scale controlled intervention trials to show that diet and exercise regimes reduce the risk of type 2 diabetes in individuals with impaired glucose tolerance (Pan et al., 1997 Tuomilehto et al., 2001 Knowler et al., 2002) and improve insulin sensitivity in normal, healthy individuals (McAuley et al., 2002). The diets in these studies were generally low fat, high fibre or high in complex carbohydrates, and in most of the studies, the subjects also engaged in regular high level aerobic exercise (two to four times per week). It is, however, impossible from these studies alone to answer the
Because of the evidence that most of the cessation-induced weight gain is due to increased eating, it has been widely accepted that efforts to prevent this weight gain through dieting will improve abstinence. However, there is little direct support for this assumption and some evidence supporting the opposite notion, that attempting to prevent moderate weight gain after quitting may be detrimental. Hall et al. (78) supplemented an intensive behavioral smoking cessation program (seven hour sessions over 2 weeks) with either (1) a behavioral weight control program (five sessions over 4 weeks consisting of daily weight and calorie monitoring, encouragement to engage in aerobic exercise 3 times per week, and behavioral self-management principles, (2) a non-specific weight control program (group therapy providing support and information on diet and exercise), or (3) standard treatment control (a printed information packet on nutrition and exercise). Unexpectedly, subjects in both weight...
As noted, an intelligent approach to strengthening exercises is necessary. Strength also may be increased with the use of an aerobic exercise machine such as an exercycle or a rowing machine. However, the principle of not becoming fatigued and exercising those muscles that can be strengthened to compensate for the weaker muscles must be applied. In general, exercise is good, but the wrong exercises may be harmful.
Return to work varies for individual patients and their type of work. Most patients can return to sedentary work 2 to 5 days after the procedure, though they should be instructed not to sit in one position for more than 30 to 40 minutes at a time in the first few weeks. Patients should not return to heavy work or lifting before week 8 and should engage in some individualized and progressive work hardening before return. In week 2, patients should be encouraged to begin exercise with walking only and to begin stretching exercises. Walking and stretching are encouraged for the remainder of the recovery period to maintain flexibility and promote healing. Jarring axial loads (Stairmaster, running, rowing, aerobics) should be avoided. Patients who are slow to recover or need more detailed instruction may be referred for a formal physical therapy program for back stabilization at 6 weeks. Athletic pursuits can be resumed in month 4 depending on tolerance of increased activity. Golf and...
Newer technologies, such as locally delivered ionizing radiation (brachy-therapy) to prevent or reduce in-stent restenosis and the use of gene-based therapy to promote neovascularization in high-risk diabetics with CAD are being explored actively. Nevertheless, we must not lose sight of the more ''traditional'' lifestyle modification interventions (weight loss, regular aerobic exercise, smoking cessation) and aggressive, multifaceted medical therapy directed toward optimized glycemic control, management of hypertension and dyslipidemia, and other secondary prevention strategies all of which, in the aggregate, are critical to enhancing improved event-free survival. This is especially important in the diabetic patient with established CAD however, the influence of aggressive primary prevention in the ''at-risk'' diabetic is equally compelling.
A low-salt diet (usually 2 g) with carbohydrate content tailored to the severity of diabetes is appropriate. It is rarely necessary to restrict salt to such a degree that the patient's diet is unpalatable nor is it ordinarily necessary to restrict water intake. Unless there is active and potentially dangerous demand ischemia or exercise-induced arrhythmias, physical activity need not be curtailed other than as dictated by symptoms. Indeed, regular aerobic exercise should be encouraged, and organized exercise conditioning programs may be beneficial. Such programs have not been convincingly shown to enhance cardiac function, but they increase exercise tolerance and have been reported to improve endothelial function. In diabetic patients, they offer the additional benefits of weight loss and enhanced control of blood glucose. Of course, smoking cessation is imperative. Smoking has specific, deleterious effects in heart failure because of vasoconstriction and reduced oxygen-carrying...
Obviously, MS does not protect you from the normal fatigue that anyone else may experience. However, a person with MS sometimes may have a short-circuiting type of fatigue. This occurs when a limb has weakness due to demyelination. if it is fatigued, the limb exhibits increased weakness due to demyelination. The limb will recover when the arm or leg is rested, but it may be bothersome when activities require its ongoing use. Repeatedly asking the demyelinated nerve to perform when it is repeatedly short-circuiting causes fatigue. The judicious use of aerobic exercise (see Chapter 20) may help build endurance, if not strength, and thus may decease this form of fatigue. However overexercising with weights increases both fatigue and weakness, so a careful balance must be sought.