rence 2.
When older adults remain healthy, they usually can climb stairs, rise from a squatting position, walk along a straight line, hop on either foot, and perform typical activities of daily living with ease.2 However, while maximum isometric contraction force is reduced approximately 20% by age 50, by age 70 the reduction reaches about 50%.2 This occurs because slower-contracting type I fibers function to maintain posture and to perform rhythmic, endurance-type exercises, while the faster-contracting type II muscle fibers that contribute to sudden powerful muscle contractions decrease with aging to a greater extent than do type I fibers.2
Regular exercise can partially overcome or significantly delay loss of muscle mass and strength, and participation in regular strength-training exercises is considered essential to staying strong and vital in one's senior years.6 By stimulating the growth of muscle and bone, strength-training exercises help to prevent osteoporosis and frailty.6 When individuals feel physically strong, mental and emotional health is promoted as well.6 Programs to guide seniors with strength training (see Strength Training for Seniors, page 30) have the potential not only to help them become stronger, but to assist with maintenance of health and independence (TABLE 2). Extensive scientific study has shown that this type of exercise is safe and effective.7 Even seniors who have never exercised before can increase muscle mass and strength through strength-training exercises.1
Pharmacist Counseling: Safe Medication Use During Exercise
Pharmacists play an important role in counseling patients who receive medication therapy while engaging in strength-training exercises. The following are examples of medications requiring special instructions for the patient:
Beta-blockers prevent the use of the target heart rate method for monitoring of endurance intensity; these agents have the potential to mask hypoglycemic symptoms other than sweating.7-9
Insulin and oral hypoglycemic agents may require dosage adjustments to avoid hypoglycemia during exercise; patients with non-insulin-dependent diabetes benefit from an exercise-induced rise in insulin sensitivity that eases the uptake of glucose by muscle tissue.7-9
Medications with the potential to cause orthostatic hypotension (e.g., antihypertensives, diuretics, antidepressants, anxiolytics, sedative-hypnotics) may require downward dosage adjustments to prevent exacerbation of orthostasis caused by fluid loss during exercise (which may result in presyncope or syncope).7-9 Patients should be made aware that adequate fluid intake is essential during exercise.7-9
Medications with anabolic activity (e.g., GH, estrogen, testosterone, vitamins) have been suggested as a modality to build muscle mass in seniors with sarcopenia.7 However, studies using various hormones have shown the following: 1) mixed results with exogenous growth hormone; 2) the effect of estrogen replacement on muscle strength is limited and inconsistent; 3) testosterone replacement for men with hypogonadism, while appearing to increase muscle strength, lacks dose-response information, and adverse effects such as prostate cancer remain a concern.7
Sedative-hypnotics can potentially reduce physical performance (i.e., directly through inhibiting effects on muscles and nerves or indirectly by a reduction in activity levels) and are associated with the risk of falls.7-9 In order to improve the safety of exercise and to increase patient adherence to an exercise program, dosage reduction or discontinuation may be required.7-9
Strength Training for Seniors
Nelson and Wernick indicate that many sedentary individuals want to change; however, they do not have the accurate and practical information necessary to commence.10 In their book entitled Growing Stronger: Strength Training for Older Adults (see Resource), Seguin et al provide a highly effective program that is safe, simple, and based on the principles of strength training.7 According to the authors, worldwide laboratory research has shown that strength trai