Exercise intensity

About: Exercise intensity is a research topic. Over the lifetime, 5459 publications have been published within this topic receiving 194298 citations. The topic is also known as: physical activity intensity.

Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory, Musculoskeletal, and Neuromotor Fitness in Apparently Healthy Adults: Guidance for Prescribing Exercise

Abstract: The purpose of this Position Stand is to provide guidance to professionals who counsel and prescribe individualized exercise to apparently healthy adults of all ages. These recommendations also may apply to adults with certain chronic diseases or disabilities, when appropriately evaluated and advised by a health professional. This document supersedes the 1998 American College of Sports Medicine (ACSM) Position Stand, "The Recommended Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory and Muscular Fitness, and Flexibility in Healthy Adults." The scientific evidence demonstrating the beneficial effects of exercise is indisputable, and the benefits of exercise far outweigh the risks in most adults. A program of regular exercise that includes cardiorespiratory, resistance, flexibility, and neuromotor exercise training beyond activities of daily living to improve and maintain physical fitness and health is essential for most adults. The ACSM recommends that most adults engage in moderate-intensity cardiorespiratory exercise training for ≥30 min·d on ≥5 d·wk for a total of ≥150 min·wk, vigorous-intensity cardiorespiratory exercise training for ≥20 min·d on ≥3 d·wk (≥75 min·wk), or a combination of moderate- and vigorous-intensity exercise to achieve a total energy expenditure of ≥500-1000 MET·min·wk. On 2-3 d·wk, adults should also perform resistance exercises for each of the major muscle groups, and neuromotor exercise involving balance, agility, and coordination. Crucial to maintaining joint range of movement, completing a series of flexibility exercises for each the major muscle-tendon groups (a total of 60 s per exercise) on ≥2 d·wk is recommended. The exercise program should be modified according to an individual's habitual physical activity, physical function, health status, exercise responses, and stated goals. Adults who are unable or unwilling to meet the exercise targets outlined here still can benefit from engaging in amounts of exercise less than recommended. In addition to exercising regularly, there are health benefits in concurrently reducing total time engaged in sedentary pursuits and also by interspersing frequent, short bouts of standing and physical activity between periods of sedentary activity, even in physically active adults. Behaviorally based exercise interventions, the use of behavior change strategies, supervision by an experienced fitness instructor, and exercise that is pleasant and enjoyable can improve adoption and adherence to prescribed exercise programs. Educating adults about and screening for signs and symptoms of CHD and gradual progression of exercise intensity and volume may reduce the risks of exercise. Consultations with a medical professional and diagnostic exercise testing for CHD are useful when clinically indicated but are not recommended for universal screening to enhance the safety of exercise.

American College of Sports Medicine Position Stand. Progression Models in Resistance Training for Healthy Adults

Abstract: In order to stimulate further adaptation toward a specific training goal(s), progression in the type of resistance training protocol used is necessary. The optimal characteristics of strength-specific programs include the use of both concentric and eccentric muscle actions and the performance of both single- and multiple-joint exercises. It is also recommended that the strength program sequence exercises to optimize the quality of the exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher intensity before lower intensity exercises). For initial resistances, it is recommended that loads corresponding to 8-12 repetition maximum (RM) be used in novice training. For intermediate to advanced training, it is recommended that individuals use a wider loading range, from 1-12 RM in a periodized fashion, with eventual emphasis on heavy loading (1-6 RM) using at least 3-min rest periods between sets performed at a moderate contraction velocity (1-2 s concentric, 1-2 s eccentric). When training at a specific RM load, it is recommended that 2-10% increase in load be applied when the individual can perform the current workload for one to two repetitions over the desired number. The recommendation for training frequency is 2-3 d x wk(-1) for novice and intermediate training and 4-5 d x wk(-1) for advanced training. Similar program designs are recommended for hypertrophy training with respect to exercise selection and frequency. For loading, it is recommended that loads corresponding to 1-12 RM be used in periodized fashion, with emphasis on the 6-12 RM zone using 1- to 2-min rest periods between sets at a moderate velocity. Higher volume, multiple-set programs are recommended for maximizing hypertrophy. Progression in power training entails two general loading strategies: 1) strength training, and 2) use of light loads (30-60% of 1 RM) performed at a fast contraction velocity with 2-3 min of rest between sets for multiple sets per exercise. It is also recommended that emphasis be placed on multiple-joint exercises, especially those involving the total body. For local muscular endurance training, it is recommended that light to moderate loads (40-60% of 1 RM) be performed for high repetitions (> 15) using short rest periods (< 90 s). In the interpretation of this position stand, as with prior ones, the recommendations should be viewed in context of the individual's target goals, physical capacity, and training status.

Superior Cardiovascular Effect of Aerobic Interval Training Versus Moderate Continuous Training in Heart Failure Patients A Randomized Study

Abstract: Background—Exercise training reduces the symptoms of chronic heart failure. Which exercise intensity yields maximal beneficial adaptations is controversial. Furthermore, the incidence of chronic heart failure increases with advanced age; it has been reported that 88% and 49% of patients with a first diagnosis of chronic heart failure are 65 and 80 years old, respectively. Despite this, most previous studies have excluded patients with an age 70 years. Our objective was to compare training programs with moderate versus high exercise intensity with regard to variables associated with cardiovascular function and prognosis in patients with postinfarction heart failure. Methods and Results—Twenty-seven patients with stable postinfarction heart failure who were undergoing optimal medical treatment, including -blockers and angiotensin-converting enzyme inhibitors (aged 75.511.1 years; left ventricular [LV] ejection fraction 29%; V u O2peak 13 mL · kg 1 · min 1 ) were randomized to either moderate continuous training (70% of highest measured heart rate, ie, peak heart rate) or aerobic interval training (95% of peak heart rate) 3 times per week for 12 weeks or to a control group that received standard advice regarding physical activity. V u O2peak increased more with aerobic interval training than moderate continuous training (46% versus 14%, P0.001) and was associated with reverse LV remodeling. LV end-diastolic and end-systolic volumes declined with aerobic interval training only, by 18% and 25%, respectively; LV ejection fraction increased 35%, and pro-brain natriuretic peptide decreased 40%. Improvement in brachial artery flow-mediated dilation (endothelial function) was greater with aerobic interval training, and mitochondrial function in lateral vastus muscle increased with aerobic interval training only. The MacNew global score for quality of life in cardiovascular disease increased in both exercise groups. No changes occurred in the control group. Conclusions—Exercise intensity was an important factor for reversing LV remodeling and improving aerobic capacity, endothelial function, and quality of life in patients with postinfarction heart failure. These findings may have important implications for exercise training in rehabilitation programs and future studies. (Circulation. 2007;115:3086-3094.)

Regulation of endogenous fat and carbohydrate metabolism in relation to exercise intensity and duration.

Abstract: Stable isotope tracers and indirect calorimetry were used to evaluate the regulation of endogenous fat and glucose metabolism in relation to exercise intensity and duration. Five trained subjects were studied during exercise intensities of 25, 65, and 85% of maximal oxygen consumption (VO2max). Plasma glucose tissue uptake and muscle glycogen oxidation increased in relation to exercise intensity. In contrast, peripheral lipolysis was stimulated maximally at the lowest exercise intensity, and fatty acid release into plasma decreased with increasing exercise intensity. Muscle triglyceride lipolysis was stimulated only at higher intensities. During 2 h of exercise at 65% VO2max plasma-derived substrate oxidation progressively increased over time, whereas muscle glycogen and triglyceride oxidation decreased. In recovery from high-intensity exercise, although the rate of lipolysis immediately decreased, the rate of release of fatty acids into plasma increased, indicating release of fatty acids from previously hydrolyzed triglycerides. We conclude that, whereas carbohydrate availability is regulated directly in relation to exercise intensity, the regulation of lipid metabolism seems to be more complex.