Maria A. Fiatarone

Exercise Training and Nutritional Supplementation for Physical Frailty in Very Elderly People

BACKGROUND Although disuse of skeletal muscle and undernutrition are often cited as potentially reversible causes of frailty in elderly people, the efficacy of interventions targeted specifically at these deficits has not been carefully studied. METHODS We conducted a randomized, placebo-controlled trial comparing progressive resistance exercise training, multinutrient supplementation, both interventions, and neither in 100 frail nursing home residents over a 10-week period. RESULTS The mean (+/- SE) age of the 63 women and 37 men enrolled in the study was 87.1 +/- 0.6 years (range, 72 to 98); 94 percent of the subjects completed the study. Muscle strength increased by 113 +/- 8 percent in the subjects who underwent exercise training, as compared with 3 +/- 9 percent in the nonexercising subjects (P < 0.001). Gait velocity increased by 11.8 +/- 3.8 percent in the exercisers but declined by 1.0 +/- 3.8 percent in the nonexercisers (P = 0.02). Stair-climbing power also improved in the exercisers as compared with the nonexercisers (by 28.4 +/- 6.6 percent vs. 3.6 +/- 6.7 percent, P = 0.01), as did the level of spontaneous physical activity. Cross-sectional thigh-muscle area increased by 2.7 +/- 1.8 percent in the exercisers but declined by 1.8 +/- 2.0 percent in the nonexercisers (P = 0.11). The nutritional supplement had no effect on any primary outcome measure. Total energy intake was significantly increased only in the exercising subjects who also received nutritional supplementation. CONCLUSIONS High-intensity resistance exercise training is a feasible and effective means of counteracting muscle weakness and physical frailty in very elderly people. In contrast, multi-nutrient supplementation without concomitant exercise does not reduce muscle weakness or physical frailty.

Exercise and physical activity for older adults

performance. Importantly, reductions in risk factors associated with disease states (heart disease, diabetes, etc.) improve health status and contribute to an increase in life expectancy. Strength training helps offset the loss in muscle mass and strength typically associated with normal aging. Additional benefits from regular exercise include improved bone health and, thus, reduction in risk for osteoporosis; improved postural stability, thereby reducing the risk of falling and associated injuries and fractures; and increased flexibility and range of motion. While not as abundant, the evidence also suggests that involvement in regular exercise can also provide a number of psychological benefits related to preserved cognitive function, alleviation of depression symptoms

Strength improvements with 1 yr of progressive resistance training in older women

Thirty-nine healthy women (59.5 +/- 0.9 yr) were randomized to either a control group (CON) or a progressive resistance training group (PRT) that trained twice weekly for 12 months. PRT trained at 80% or more (average of 84%) of their most recent one repetition maximum (1RM) on the lateral pull-down (LPD), knee extensor (KE), and double leg press (DLP) apparatus. One RM was measured for each exercise once monthly in PRT and at baseline, midstudy, and end of study in CON. One RM significantly increased in PRT for all muscle groups trained compared to CON (P < 0.0001). Increases of 73.7 +/- 12%, 35.1 +/- 3%, and 77.0 +/- 5%, respectively, for KE, DLP, and LPD in PRT and 12.7% +/- 8%, 3.7% +/- 3%, and 18.4% +/- 4%, respectively, in CON were observed. Approximately 50% of the gains in KE and LPD and 40% in the DLP were seen in the first 3 months of the study. In all three exercises, strength gains in PRT continued over the entire 12-month period. These data indicate that high-intensity strength training results in substantial, continual increases in strength in postmenopausal women for at least 12 months, with the greatest gains seen in the first 3 months of training.

The Boston FICSIT study : the effects of resistance training and nutritional supplementation on physical frailty in the oldest old

Research indicates that lower extremity muscle weakness in the elderly is consistently related to impaired mobility and fall risk. Reversible components of the muscle weakness of aging include underuse syndromes and undernutrition, both of which are prevalent in nursing home populations. The Boston FICSIT study is a nursing home‐based intervention to improve muscle strength through progressive resistance training of the lower extremities and/or multi‐nutrient supplementation in chronically institutionalized subjects aged 70–100. Baseline measurements of falls, medical status, psychological variables, functional status, nutritional intake and status, body composition, muscle mass and morphology, muscle function, and gait and balance are taken. The nursing home residents are then randomly assigned to one of four treatment groups for 10 weeks: (1) high intensity progressive resistance training of the hip and knee extensors 3 days per week; (2) multi‐nutrient supplementation with a 360‐kcal high carbohydrate, low fat liquid supplement every day; (3) a combination of groups (1) and (2); and (4) a control group. Both non‐supplemented groups receive a liquid placebo every day, and both non‐exercising groups attend three sessions of “leisure activities” every week in order to control for the attentional aspects of the exercise and nutritional interventions. At the end of the 10‐week period, all baseline measurements are re‐assessed.

Leg power in young women : relationship to body composition, strength, and function

The ability to generate high forces at high velocity (power) is an important component of physiologic reserve for both athletic performance and functional capacity. A comparison was made between different laboratory methods and field tests designed to evaluate leg power. Nineteen young healthy untrained women participated in this study. Maximum power during the double leg press (KP) occurred between 56-78% of the one repetition maximum (1-RM) and averaged (404 +/- 22 W). Rank-ordered correlation showed an association between KP and another measure of leg power measured on the leg extensor power rig (LR) when expressed per kg LBM (Rho = 0.565, P < 0.016). KP was also related to the 1-RM achieved on the double leg press (R2 = 0.584, P < 0.001). The KP test also correlated with the vertical jump (R2 = 0.538, P < 0.004) and maximal power output during the Wingate anaerobic power test (R2 = 0.299, P < 0.015). However, double leg press power was not related to time to run 40 yards (R2 = 0.020, P < 0.573) or maximal gait velocity (R2 = 0.136, P < 0.121). These results suggest that maximal power during the double leg press occurs at a higher percentage of maximal strength than previously reported. Double leg press power was related to vertical jump performance, validating this field test as a measure of leg muscle power in young women.

A multi-center comparison of dual energy X-ray absorptiometers: In vivo and in vitro soft tissue measurement

Objective: To assess intra- and inter-site soft tissue variability by dual energy X-ray absorptiometry (DXA). Design: Cross-sectional trial. Setting: Three medical research institutions. Subjects: Five humans (in vivo) and four phantoms (in vitro), configured from two whole body phantoms with artificial skeletons and thickness overlays. Interventions: Duplicate total-body DXA scans were performed on all subjects at each institution within a 15 d period. Results: All intra-site coefficients of variation (CV) were <0.5% for total tissue mass, but in vitro and in vivo Cvs were 7.2% and 2.3% for fat mass (FM) and 2.5% and 0.9% for lean mass (LM), respectively. Several total-body and regional FM and LM measurements were significantly different between sites (P < 0.05), with percent differences between sites ranging from 2.6–13.3% for FM and from 1.6–13.6% for LM. Site 2 was consistently lower for FM and Site 3 was consistently lower for LM. Conclusions: These results stress the need for both rigorous and standardized cross-calibration procedures for soft tissue measurement by DXA. Sponsorship: This work has been supported in part by NIH Training Grant #T32AG00209, grant P01-DK42618 from the National Institutes of Health, federal funds from the US Department of Agriculture, and Agricultural Research Services contract 53-3K06-5-10. Dr Nelson is currently a Brookdale National Fellow.

A 20-yr longitudinal study of Olympic oarsmen.

Nine 1972 silver-medalist oarsmen were studied before the Olympic Games and 10 and 20 yr later. Peak power, metabolic responses, and heart rate were recorded during rowing ergometry; blood lactate was measured following exercise. The skinfold equation yielded percent body fat. The average change (multiple analysis of variance) among measurements from 1972 to 1992 was 37.5 +/- 3% (P < 0.01). Average changes between 1972 and 1982 and between 1982 and 1992 were similar, 17 and 18%, respectively (P < 0.01). The most significant change between 1972 and 1992 was decreased peak blood lactate (106%). Decreases in peak power, VE, and VO2 (ml.kg-1.min-1) were all similar, approximately 40%, and were significant. Body fat increased (from 12.3 to 15.6%), and absolute VO2 and relative VO2 (lean body mass) decreased 30% (P < 0.01). Only body weight, heart rate, and O2 pulse showed smaller changes, but these changes were still significant (P < 0.05). Relative peak VO2 decreased from 65.5 to 46.8 ml.kg-1.min-1 from 1972 to 1992 and at a rate of 10%.decade-1. The most significant changes between 1972 and 1982 were increases in percent body fat (from 12.3 to 16.3%) and decreases in VO2 values (P < 0.01). There was less change in body fat between 1982 and 1992, but lactate significantly decreased (P < 0.01), as did peak power and absolute and relative VO2 and VE. Although fitness levels in former elite oarsmen decreased each decade, these declines were somewhat arrested by regular aerobic training. Body fat increased and metabolic capacity decreased rapidly during the first decade, whereas anaerobic capacity decreased more significantly in the second decade. Anaerobic capacity diminished at a significantly greater rate than aerobic capacity, probably as a result of the aging process and emphasis on aerobic training in post-competitive years.

Military body fat standards and equations applied to middle-aged women

Military circumference equations are used to assess compliance of military personnel with body fat (BF) standards. The purpose of the present study was to determine the ability of military equations to correctly classify 62 women aged 40-60 yr (50.9 +/- 6.2, mean +/- SD) as overfat or underfat using underwater weighing (UWW) as the reference method and military BF standards as diagnostic cutoffs. Values for the mean +/- SD percent BF from UWW, Army, Marine Corps, and Navy equations were 29.5 +/- 7.1, 27.3 +/- 4.7, 25.7 +/- 5.8, and 30.3 +/- 5.1, respectively. The Army and Marine Corps equations underpredicted percent BF compared to UWW, P < 0.05. Bland-Altman plots showed a lack of agreement in predicting percent BF in women 40-60 yr between equation and UWW-derived percent BF. This finding was supported by the low agreement in correctly classifying an individual as meeting or exceeding the BF standards, range 25%-57%, Cohens kappa. The low sensitivities (range 20%-74%) and higher specificities (range 80%-98%) of the equations indicated they identified individuals who met the BF standards better than those who exceeded them. Caution must be exercised when using military prediction equations to assess compliance with military BF standards in healthy middle-aged women.