New Recommendations Answer Question of How Much Exercise Is Enough

Health and fitness professionals now may customize exercise prescriptions for healthy adults with the help of new recommendations released recently by the American College of Sports Medicine (ACSM). The position stand, Quantity and Quality of Exercise for Developing and Maintaining Cardiorespiratory, Musculoskeletal, and Neuromotor Fitness in Apparently Healthy Adults: Guidance for Prescribing Exercise, reflects current scientific evidence on physical activity and includes recommendations on aerobic exercise, strength training, and flexibility.

Consistent with the 2008 Physical Activity Guidelines for Americans, the overall recommendation is for most adults to engage in at least 150 minutes of moderate-intensity exercise each week. The recommendations for cardiorespiratory exercise are as follows:
•Meet the minimum weekly exercise recommendation through 30 to 60 minutes of moderate-intensity exercise 5 days per week or 20 to 60 minutes of vigorous-intensity exercise 3 days per week.

•To accumulate the desired amount of daily exercise, perform exercises in 1 continuous session or in multiple shorter sessions (at least 10 minutes each).

•For best adherence and to minimize the risk of injury, progress gradually in exercise time, frequency, and intensity.

•Persons who cannot meet these minimums can still engage in some activity to achieve some benefit.

The recommendations for resistance exercise are as follows:
•Train each major muscle group 2 or 3 days each week. Use a variety of exercises and equipment.

•Older persons or previously sedentary adults who are starting out should exercise with very light or light intensity for best results.

•Perform 2 to 4 sets of each exercise to improve strength and power.

•For each exercise, perform 8 to 12 repetitions to improve strength and power and 15 to 20 repetitions to improve muscular endurance; middle-aged and older persons who are starting exercise should perform 10 to 15 repetitions to improve strength.

•Perform resistance training sessions at least 48 hours apart.

The recommendations for flexibility exercise are as follows:
•Perform flexibility exercises at least 2 or 3 days each week to improve range of motion.

•Hold each stretch for 10 to 30 seconds to the point of tightness or slight discomfort.

•Repeat each stretch 2 to 4 times, accumulating 60 seconds per stretch.

•Perform static, dynamic, ballistic, or proprioceptive neuromuscular facilitation stretches, all of which are effective.

The recommendations for neuromotor exercise are as follows:
•Perform this kind of exercise 2 or 3 days per week.

•Older adults should make sure that exercises involve motor skills (balance, agility, coordination, and gait), proprioceptive exercise training, and multifaceted activities (tai chi and yoga) to improve physical function and prevent falls.

•Perform exercise for 20 to 30 minutes per day.

The ACSM position stand also clarifies the following points:
•Pedometers, step-counting devices used to measure physical activity, do not provide an accurate measure of exercise quality and should not be used as the sole measure of physical activity.

•All adults should be able to recognize the warning signs of heart disease, and all health care providers should ask patients about these symptoms.

•Keep in mind that meeting the guidelines for physical activity does not make up for a sedentary lifestyle, which has been shown to be a health risk in itself.

The ACSM also released a report indicating that although muscle strength may be maintained with just 1 day per week of exercise, older adults may need more frequent exercise than younger adults to maintain muscle mass gained from resistance exercise. Researchers suggested that training 1 day per week can be effective during temporary periods when it is difficult to maintain a consistent, intensive exercise regimen several days per week.

The exercise recommendations position stand was published in the July 2011 issue of Medicine & Science in Sports & Exercise, the official journal of the ACSM. For more information about exercise, visit the ACSM Web site at http://www.acsm.org. Or, contact the organization at American College of Sports Medicine, PO Box 1440, Indianapolis, IN 46206-1440; telephone: (317) 637-9200; fax: (317) 634-7817.