Vol. 19 Issue 19
subacute and long-term care
Strength Training in the Frail Elderly
This is part 1 of a two-part column.
As a person ages, one of the changes that occurs is a decline in musculoskeletal system function. The result is a condition called sarcopenia, or a gradual loss of muscle tissue with aging.
Sarcopenia leads to decreased strength, decreased power and ultimately decreased functional mobility. Sarcopenia contributes to frailty, decreased independence and increased health care costs.
Essentially, we need more than 30 percent of normal strength to function adequately (below 30 percent, frailty occurs). At age 30, we have approximately 70 percent of normal strength reserve (an average adult) and it continues to decline about 1 percent per year.
In the elderly population, the decline increases to between 1 to 3 percent per year. Strengthening exercises can decrease the rate of muscle function loss as we age. This article will focus on research on strengthening in the elderly and some assessment tools that may be used to examine overall strength in the elderly. Next month's article will focus on ways to treat elderly and frail patients who need to improve their muscle strength and functional activity.
Looking at Research
Two classic studies by Fiatarone looked at the older, more frail elderly to determine the effects of strength training. In her first study, Fiatarone studied 10 long-term care residents aged 86 to 96.1 She performed eight weeks of strength training of the knee extensors at 50 percent of the resident's one-repetition maximum (1 RM) followed by seven weeks at 80 percent of the resident's one repetition max.
The result was a mean increase in leg extensor strength of 254 percenta mean increase in cross sectional area of 15 percent and improvement in functional mobility. She later studied 100 frail long-term care residents with a mean age of 87 years old.2 She compared hip and knee extensor strength in an exercise group (resistance training at 80 percent of the resident's 1 RM) to a control group (aerobic or flexibility activities) over 10 weeks of training. The results are seen in Table 1.
Strength also has some interaction with elderly balance. A study by Hess and Woolacott looked at ambulatory and community-dwelling elderly aged 74 to 96 years.3They compared a strength training group exercising three times a week and performing three sets of eight repetitions for each muscle group (e.g., ankle dorsiflexors, ankle plantarflexors, knee flexors, knee extensors) over a 10-week period to a control group that did no exercise for 10 weeks. In week 1, the strength training group performed at 50 percent of their estimated 1RM and then 80 percent of their estimated 1RM in the second week through the tenth. Results are seen in Table 2. The strength training group showed significant improvement compared to the group that did not exercise in both strength and balance measures.
Gross Strength Assessment
To measure gross lower-extremity strength function, sit-to-stand tests can be used. The 30-Second Chair Rise is one such test.4The patient sits in a chair with arms across the chest and is asked to go from sitting to standing as many times as he can in 30 seconds. The number of chair rises is counted and can be compared to established normative ranges (see Table 3). Pushing off chair armrests or using a cane or walker must be recorded as adaptation with an official score of zero. Even if the patient is unable to sit to stand without assist, use the performance as a baseline from which to gauge improvement.
To measure gross upper-extremity strength function, the Arm Curl Test can be used.4The patient sits in a chair and curls a weight from full extension, hand shake position to full flexion, palms toward shoulder position. Using a lower weight is considered an adaptation with an official test score of zero if comparing to established norms. The adapted score is recorded as a baseline measure in order to gauge improvement. Table 4 shows arm curl normative ranges. n
1. Fiatarone, M., Marks, E., Ryan, N., et al. (1990). High intensity strength training in nonagenarians: Effects on skeletal muscle. Journal of the American Medical Association, 263, 3029-3034.
2. Fiatarone, M. et al. (1994). Exercise training and nutritional supplementation for physical frailty in very elderly people. New England Journal of Medicine, 330(25), 1769-1776.
3. Hess, J., & Woollacott, M. (2005).ÊEffect of high-intensity strength-training on functional measures of balance ability in balance-impaired older adults.ÊJournal of Manipulative Physiological Therapy, 28(8), 582-590.
4. Rikli, J. (2001). The Senior Fitness Test. Human Kinetics.
Bob Thomas is a geriatric physical therapist who currently serves as the president of Infinity Rehab, a provider of rehab in subacute and long-term care facilities, hospitals, schools and outpatient settings in seven states. He lectures nationally on rehab for the frail older population for Great Seminars and Books Inc. and is an adjunct professor in the physical therapy program at Pacific University in Hillsboro, OR.