Friday, July 2, 2010

About PACE

Progressively Accelerating Cardiopulmonary Exertion (PACE)
– A More Effective Alternative to Modern Exercise Prescriptions

This following is an article from a news letter from Dr. Al Sears (USA)

Ask a personal trainer, pick up a fitness magazine, or consult a medical organization and you will see the same fitness-training concepts. These modern exercise prescriptions will be cardiovascular endurance training (CVE) or “cardio” for short, “aerobic” exercises often given in hour-long group classes, and weight training on machines or with free-weights. These forms of exercise, while promoted by a majority of physicians and fitness professionals, fail to bring about the physiological adaptations necessary for a healthy and vital cardiopulmonary system and may leave patients at a heightened risk of mortality.

The key failing of both cardiovascular endurance training and aerobics classes is the focus on exercise duration at the expense of intensity. In order to achieve the recommended durational benchmarks (typically a minimum of 30 minutes), exercise participants are forced to reduce exercise intensity into the low to moderate range. Yet the data demonstrate an unequivocal advantage of exercise intensity over duration. For example, in a study published in the Archives of Internal Medicine, 8896 recreational runners were asked to report their average running duration and intensity. The results illustrated that increased intensity was significantly associated with lower blood pressure, lower triglycerides, lower CHOL/HDL ratios, lower BMIs, and lower waist, hip, and chest circumferences. Exercise duration had no effect on these parameters.1 Similarly, data from the Harvard Alumni Health Study demonstrated a significant inverse relationship between intense physical activity and mortality,2 with low-intensity exercise failing to decrease the risk of all-cause mortality. The Harvard data also revealed that long-duration exercise did not reduce the risk of coronary heart disease. High-intensity exercise, however, resulted in a decreased risk of CHD.3

In addition to failing to protect against all-cause mortality and CHD, non-vigorous durational exercise also fails to challenge the heart and lungs to achieve and maintain the capacity necessary to respond to sudden and unexpected increases in demand.4,5 This problem worsens with aging because both lung size and cardiac output decline with age. Of even greater concern is the evidence that repeated durational challenges with low-intensity exercise may actually reduce cardiac function.6 These findings are of paramount importance in light of the fact that even moderate reductions in cardiopulmonary capacity dramatically increase the risk of disease progression and mortality.7,8

As health-care professionals, we must recognize that exercise is not all one thing. Different types of exercise challenges produce different, even opposite, physiological adaptations. It is clear that exercise intensity is the key to promoting good cardiopulmonary capacity and in combating modern deconditioning and age-related losses. We must also recognize, however, that the average deconditioned patient is not capable of safely or effectively participating in most high-intensity training programs. We can find a solution to this problem and the key to optimal cardiovascular conditioning at any age in two concepts: Progressivity and Acceleration. Progressivity in exercise refers to a regular and consistent increase in the intensity of demands placed on the cardiovascular system. Progressivity takes into consideration the baseline fitness level of each patient and allows safe incremental increases in intensity, regardless of the current level of conditioning. Acceleration refers to training the cardiovascular system to respond more quickly to increases in demands, as well as reducing the amount of time it takes for the heart and lungs to recover from exertion. Primary research data will be presented suggesting that a program of Progressively Accelerating Cardiopulmonary Exertion (PACE) conditions the heart and lungs to build larger reserve capacities to respond adequately to large and sudden increases in demands. PACE is the first and only program to offer the benefits of improved cardiovascular capacity to patients of all ages and all fitness levels.

LEARNING OBJECTIVES
1) Understand how modern exercise programs fail to contribute to improved cardiopulmonary fitness and how they may be increasing the risk of mortality.
2) Understand the importance of cardiopulmonary capacity and how it relates to longevity.
3) Understand the key components of the PACE program and how it provides a safe and effective way to improve cardiopulmonary capacity and decrease cardiopulmonary aging and disease and subsequent mortality.

References:

1 Williams P. Relationships of heart disease risk factors to exercise quantity and intensity. Arch Intern Med. 1998;158(3):237-245.
2 Lee IM, Hsieh, CC, Paffenparger, RS Jr. Exercise intensity and longevity in men. The Harvard Alumni Health Study. JAMA. 1995;273(15):1179-1184
3 Lee IM, Sesso HD, Paffenparger, RS Jr. Physical activity and coronary heart disease risk in men: does the duration of exercise episodes predict risk? Circulation. 2000;102(9): 981-986.
4 Baily S, Wilkerson DiMenna F, Jones A. Influence of repeated sprint training on pulmonary O2 uptake and muscle deoxygenation kinetics in humans. J Appl Physiol. 2009 Jun;106(6):1875-87.
5 Adachi H, Koike A, Obayashi T, et al. Does appropriate endurance exercise training improve cardiac function in patients with prior myocardial infarction? Eur Heart J. 1996 Oct;17(10):1511-21.
6 Oberman, A, Fletcher F, Lee J, et al. Efficacy of high-intensity exercise training on left ventricular ejection fraction in men with coronary artery disease (the Training Level Comparison Study). Am J Cardiol. 1995 Oct 1;76(10):643-7.
7 Schunemann H, et al. Pulmonary function is a long-term predictor of mortality in the general population: 29-year follow-up of the Buffalo Health Study. Chest. 2000 Sep;118(3):656-64.
8 Kannel WB, Seidman JM, Fercho W, Castelli WP. Vital Capacity and Congestive Heart Failure. The Framingham Study. Circulation. 1974;49(6):1160-1166.


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