Resistance training improves fatigue and quality of life in previously sedentary breast cancer survivors: a randomised controlled trial.

The primary aim of this study was to evaluate the benefits of resistance training (RT) on quality of life (QOL) and fatigue in breast cancer survivors as an adjunct to usual care. We recruited 39 women who had survived breast cancer [mean age (y) 51.9 ± 8.8; time since diagnosis (m) 11.6 ± 13.2]. Primary outcomes were fatigue as assessed by the Functional Assessment of Chronic Illness Therapy - Fatigue (FACIT) scale and QOL as assessed by the Functional Assessment of Cancer Therapy - General (FACT-G) scale. ANCOVA was used to assess the change in the primary outcomes while controlling for baseline values, with effect sizes (ES) displayed as partial Eta squared. The experimental group received supervised RT 3 days per week in a university clinic for 16 weeks. Perceptions of fatigue improved significantly in the RT group compared to controls [mean (SD) 6.7 (7.5) points vs. 1.5 (3.7) points], (P = 0.006, ES = 0.20) as did QOL [6.9 (8.5) points vs. 1.6 (4.4) points], (P = 0.015, ES = 0.16). We demonstrated both statistically and clinically important improvements in fatigue and QOL in response to RT in breast cancer survivors.

Estimation of lean body weight in older women with hip fracture.

OBJECTIVE: Lean body weight (LBW) decreases with age while total body fat increases, resulting in altered drug pharmacokinetics. A semi-mechanistic equation estimating LBW using height, weight and sex has been developed for potential use across a wide range of body compositions. The aim of this study was to determine the ability of the LBW equation to estimate dual energy x-ray absorptiometry-derived fat free mass (FFM(DXA)) in a population of older women with recent hip fracture. METHODS: Baseline, four and 12 month data obtained from 23 women enrolled in the Sarcopenia and Hip Fracture study were pooled to give 58 measurements. LBW was estimated using the equation: LBW (kg) = (9270 x Wt) / (8780 + (244 x BMI)). Body composition was classified as: 'normal' (BMI <25kg/m(2) and not sarcopenic), 'overweight-obese' (BMI >25kg/m(2) and not sarcopenic), 'sarcopenic' (sarcopenic and BMI <25kg/m(2)), or 'sarcopenic-obese' (sarcopenic and BMI >25kg/m(2)). The ability of the LBW equation to predict FFMDXA was determined graphically using Bland-Altman plots and quantitatively using the method of Sheiner and Beal. RESULTS: The mean ± SD age of female participants women was 83±7 years (n=23). Sarcopenia was frequently observed (65.2%). Bland-Altman plots demonstrated an underestimation by the LBW equation compared to FFMDXA. The bias (95% CI) and precision (95% CI) calculated using the method of Sheiner and Beal was 0.5kg (-0.7, 1.66kg) and 4.4kg (-3.7, 12.4kg) respectively for pooled data. CONCLUSION: This equation can be used to easily calculate LBW. When compared to FFMDXA, the LBW equation resulted in a small underestimation on average in this population of women with recent hip fracture. The degree of bias may not be clinically important although further studies of larger heterogeneous cohorts are needed to investigate and potentially improve the accuracy of this predictive equation in larger clinical cohorts.

The effect of high-intensity progressive resistance training on adiposity in children: a randomized controlled trial.

BACKGROUND: High-intensity progressive resistance training (PRT) improves adiposity and metabolic risk in adults, but has not been investigated in children within a randomized controlled trial (RCT). OBJECTIVE: We hypothesized that high-intensity PRT (8 weeks, twice a week) would decrease central adiposity in children, as assessed via waist circumference. METHODS DESIGN/SETTING/PARTICIPANTS: Concealed randomization stratified by age and gender was used to allocate rural New Zealand school students to the wait-list control or PRT group. INTERVENTION: Participants were prescribed two sets (eight repetitions per set) of 11 exercises targeting all the major muscle groups at high intensity. PRIMARY OUTCOME: Waist circumference; secondary outcomes included whole body fat, muscular fitness (one repetition maximum), cardiorespiratory fitness (peak oxygen consumption during a treadmill test), lipids, insulin sensitivity and fasting glucose. RESULTS: Of the 78 children (32 girls and 46 boys; mean age 12.2(1.3) years), 51% were either overweight (33%) or obese (18%). High-intensity PRT significantly improved waist circumference (mean change PRT -0.8 (2.2) cm vs +0.5 (1.7) cm control; F=7.59, P=0.008), fat mass (mean change PRT +0.2 (1.4) kg vs +1.0 (1.2) kg control; F=6.00, P=0.017), percent body fat (mean change PRT -0.3 (1.8)% vs +1.2 (2.1)% control; F=9.04, P=0.004), body mass index (mean change PRT -0.01 (0.8) kg m(-2) vs +0.4 (0.7) kg m(-2) control; F=6.02, P=0.017), upper body strength (mean change PRT+11.6(6.1) kg vs +2.9(3.7) kg control; F=48.6, P<0.001) and lower body strength (mean change PRT +42.9(26.6) kg vs +28.5(26.6) kg control; F=4.72, P=0.034) compared to the control group. Waist circumference decreased the most in those with the greatest baseline relative strength (r=-0.257, P=0.036), and greatest relative (r=-0.400, P=0.001) and absolute (r=0.340, P=0.006) strength gains during the intervention. CONCLUSION: Isolated high-intensity PRT significantly improves central and whole body adiposity in association with muscle strength in normal-weight and overweight children. The clinical relevance and sustainability of these changes in adiposity should be addressed in future long-term studies.

Effects of resistance training on metabolic fitness in children and adolescents: a systematic review.

The majority of resistance training (RT) research with children to date has focused on pre-adolescents and the safety and efficacy of this type of training rather than the potential metabolic health benefits. Our objectives, using computerized databases, were (i) to systematically review studies utilizing RT interventions with children and adolescents <18 years; (ii) to investigate the metabolic health outcomes (adiposity, lipids, insulin, glucose) associated with RT; (iii) to provide recommendations for future investigations. A total of 12 studies met the review criteria. There is only a small amount of evidence that children and adolescents may derive metabolic health-related adaptations from supervised RT. However, methodological limitations within the body of this literature make it difficult to determine the optimal RT prescription for metabolic fitness in children and adolescents, and the extent and duration of such benefits. More robustly designed single modality randomized controlled trials utilizing standardized reporting and precise outcome assessments are required to determine the extent of health outcomes attributable solely to RT and to enable the development of evidence-based obesity prevention and treatment strategies in this cohort.

Degenerative meniscus tears and mobility impairment in women with knee osteoarthritis.

OBJECTIVE: Meniscus tears are often presumed to be associated with a traumatic event, but they can also occur as a result of the cartilage degeneration process in osteoarthritis (OA). The aim of this paper is to describe the prevalence and clinical correlates of degenerative meniscus tears in women with knee OA. METHOD: The subjects were women screened for a double-blind, sham-exercise controlled clinical trial for women over 40 years of age with OA in at least one knee, according to American College of Rheumatology (ACR) clinical criteria. The presence of meniscus tears was assessed via a 3T Intera (Philips Medical Systems) magnetic resonance image (MRI). Clinical examination included a history of arthritis onset and physical examination of the lower extremities. Physical assessments included body composition, muscle strength, walking endurance, gait velocity, and balance. In addition, pain and disability secondary to OA, physical self-efficacy, depressive symptoms, habitual physical activity level and quality of life were assessed via questionnaires. RESULTS: Almost three-quarters (73%) of the 41 subjects had a medial, lateral, or bilateral meniscus tear by MRI. Walking endurance and balance performance were significantly impaired in subjects with a degenerative meniscus tear, compared to subjects without tears, despite similar OA duration, symptoms, and disability, body composition, and other clinical characteristics. CONCLUSION: Meniscus tears, diagnosed by MRI, are very common in older women with knee OA, particularly in the medial compartment. These incidentally discovered tears are associated with clinically relevant impairments of balance and walking endurance relative to subjects without meniscus tears. The explanation for this association requires further study.

Creatine supplementation does not enhance submaximal aerobic training adaptations in healthy young men and women.

The benefits of dietary creatine supplementation on muscle performance are generally related to an increase in muscle phosphocreatine content. However, creatine supplementation may benefit endurance sports through increased glycogen re-synthesis following exercise. This study investigated the effect of creatine supplementation on muscle glycogen content, submaximal exercise fuel utilisation and endurance performance following 4 weeks of endurance training. Thirteen healthy, physically active, non-vegetarian subjects volunteered to take part and completed the study. Subjects were supplemented with either creatine monohydrate (CREAT, n = 7) or placebo-maltodextrin (CON, n = 6). Submaximal fuel utilisation and endurance performance were assessed before and after a 4 week endurance training program. Muscle biopsies were also collected before and following training for assessment of muscle creatine and glycogen content. Training increased quadriceps glycogen content to the same degree (approximately 20%) in both groups (P = 0.04). There was a significant training effect on submaximal fuel utilisation and improved endurance performance. However, there was no significant treatment effect of creatine supplementation. Creatine supplementation does not effect metabolic adaptations to endurance training.

The influence of physical activity on abdominal fat: a systematic review of the literature.

UNLABELLED: The relationship between excess abdominal adipose tissue, metabolic and cardiovascular health risk has stimulated interest in the efficacy of physical activity in specifically perturbing this adipose depot. The evolution of imaging techniques has enabled more direct measurement of changes in abdominal and visceral fat. The purpose of this summary was to systematically review the relationship between physical activity and abdominal fat. METHODS: Database searches were performed on MEDLINE, CINAHL, SPORT DISCUS and PUBMED, from 1985 to 2005 with keywords "exercise", "abdominal fat" and "visceral fat". RESULTS: Nineteen randomized controlled trials (RCTs) and eight non-randomized controlled trials were selected. In RCTs using imaging techniques to measure change in abdominal fat in overweight or obese subjects, seven out of 10 studies (including three trials with type 2 diabetics) reported significant reductions compared with controls. Reductions in visceral and total abdominal fat may occur in the absence of changes in body mass and waist circumference. Waist-to-hip ratio is not a sensitive measure of change in regional adiposity in exercise studies. No studies fulfil the Consolidated Standards of Reporting Trials (CONSORT) statement's criteria for the highest quality of randomized trial; however, many studies were in progress or published before the opportunity to comply with these recommendations. Therefore, limited evidence from a number of studies suggests a beneficial influence of physical activity on reduction in abdominal and visceral fat in overweight and obese subjects when imaging techniques are used to quantify changes in abdominal adiposity. More rigorous studies are needed to confirm these observations.

Longitudinal muscle strength changes in older adults: influence of muscle mass, physical activity, and health.

The longitudinal changes in isokinetic strength of knee and elbow extensors and flexors, muscle mass, physical activity, and health were examined in 120 subjects initially 46 to 78 years old. Sixty-eight women and 52 men were reexamined after 9.7 +/- 1.1 years. The rates of decline in isokinetic strength averaged 14% per decade for knee extensors and 16% per decade for knee flexors in men and women. Women demonstrated slower rates of decline in elbow extensors and flexors (2% per decade) than men (12% per decade). Older subjects demonstrated a greater rate of decline in strength. In men, longitudinal rates of decline of leg muscle strength were approximately 60% greater than estimates from a cross-sectional analysis in the same population. The change in leg strength was directly related to the change in muscle mass in both men and women, and it was inversely related to the change in medication use in men. Physical activity declined yet was not directly associated with strength changes. Although muscle mass changes influenced the magnitude of the strength changes over time, strength declines in spite of muscle mass maintenance or even gain emphasize the need to explore the contribution of other cellular, neural, or metabolic mediators of strength changes.

The effect of oral nutritional supplements on habitual dietary quality and quantity in frail elders.

BACKGROUND: Frail institutionalized elders have a high prevalence of nutritional risk factors, undernutrition, weight loss, and nutrition-related morbidity and excess mortality. Little information is available on effective means to intervene in this setting. HYPOTHESES: We tested the hypothesis that addition of multinutrient oral supplements to the diet of frail elders would improve their overall nutritional status and functional level. METHODS: Fifty nursing home residents aged 88+/-1 yr. were followed for 10 weeks in the course of a randomized controlled trial of supplementation with a multinutrient liquid supplement vs. a non-nutritive placebo drink. Three-day food weighing was used to analyze their habitual dietary intake before and during the final week of the intervention. Nutritional status was further assessed with nutritional biochemistries, anthropometric measurements, and body composition analysis as well as physical and functional performance tests. RESULTS: The nutritional supplement was consumed with high compliance, but did not significantly augment total caloric intake. Supplementation was associated with significant reductions in total energy, protein, fat, water, fiber, and many vitamins and minerals in the habitual diet of these nursing home residents. Nutritional status improved in terms of folate levels in serum, but no other measured vitamin or mineral indices. Body composition analysis revealed a small gain in weight, increases in fat stores, but no improvement in lean tissue mass associated with supplemention. No physical performance or functional gains were associated with supplementation. CONCLUSION: Short-term nutritional supplementation in elders at nutritional risk is offset by simultaneous reduction in voluntary food intake. It seems likely that changing other components of energy expenditure such as physical activity levels or basal metabolism may be required to produce overall improvements in nutritional intake in this setting.

Bone mineral measurements: a comparison of delayed gamma neutron activation, dual-energy X-ray absorptiometry and direct chemical analysis.

A system in vitro consisting of a femur from a cadaver and soft-tissue equivalent material was used to test the agreement between several techniques for measuring bone mineral. Calcium values measured by delayed gamma neutron activation (DGNA) and bone mineral content (BMC) by Lunar, Hologic and Norland dual-energy X-ray absorptiometers (DXA) were compared with calcium and ash content determined by direct chemical analysis. To assess the effect of soft-tissue thickness on measurements of bone mineral, we had three phantom configurations ranging from 15.0 to 26.0 cm in thickness, achieved by using soft-tissue equivalent overlays. Chemical analysis of the femur gave calcium and ash content values of 61.83 g +/- 0.51 g and 154.120 +/- 0.004 g, respectively. Calcium measured by DGNA did not differ from the ashed amount of calcium at any of the phantom configurations. The BMC measured by DXA was significantly higher, by 3-5%, than the amount determined by chemical analysis for the Lunar densitometer and significantly lower, by 3-6%, for the Norland densitometer (p<0.001-0.024), but only 1% lower (not significant) for the Hologic densitometer. DXA instruments showed a decreasing trend in BMC as the thickness increased from 20.5 to 26.0 cm (p<0.05). However, within the entire thickness range (15.0-26.0 cm), the overall influence of thickness on BMC by DXA was very small. These findings offer insight into the differences in these currently available methods for bone mineral measurement and challenge the comparability of different methods.