Insulin-like growth factor-1 (IGF-1) is related to the preservation of lean body mass. Its decline during ageing is thought to make old adults more susceptible to sarcopenia and functional dependency. The aim of the present study was to investigate circulating total IGF-1 in old adults who engaged in a 12-weeks of progressive resistance training.
Aims: Benefits of resistance exercise in elderly people are well documented; however, sustaining these benefits can be difficult and adherence is often poor. Muscular strength and physical function usually decline after a supervised resistance exercise program (REP). We investigated these changes in older adults during an observational follow-up and whether leisure time physical activity (LTPA) or unsupervised resistance exercise (RE) limit these changes. Methods: Subjects (N=236, 73.7±5.7 years, 58.2% female) had participated in a supervised 12-week REP. Quadriceps strength and timed-up-and-go performance (TUG) at follow-up were compared to values before and after REP. Multivariate statistics were used to predict changes in strength or function. Results: Two hundred and eleven (90.3%) participants completed REP and 149 (63.1%) completed follow-up (11.4±2.9 months). Quadriceps strength at follow-up decreased significantly compared to after REP (–27N), but was higher than before REP (+30N). TUG did not decrease during follow-up and was better than before REP (–0.9 seconds). LTPA (+38.0N, p<0.001) and RE (+31.6N, p=0.006) predicted strength at follow-up, although they did not completely prevent loss of strength during follow-up. Conclusions: Quadriceps strength declines after a 12-week resistance exercise program in older adults. Neither LTPA nor RE completely prevents loss of quadriceps strength during follow-up, although they limited the loss. TUG did not change during follow-up and was better at follow-up than before the start of the resistance exercise program.
Aging is associated with an impairment of blood lipids. The present study investigated the response of blood lipids to resistance exercise in old adults. The particular aim was to investigate whether the response of blood lipids is associated with changes in body composition of blood lipid medication.
BACKGROUND/OBJECTIVES: A few previous studies indicate that protein supplementation increases gains in muscle mass and strength during a resistance exercise program. The purpose of this study was to investigate whether whey protein supplementation results in greater increases in lean body mass, muscle strength and physical function in elderly individuals during 12 weeks of resistance exercise when compared to isocaloric carbohydrate supplementation.SUBJECTS/METHODS: A total of 161 men and women, 65-91 years old, participated in a randomized, controlled, double-blind intervention study, involving dietary supplementation and a 12-week resistance exercise program, designed to increase muscle mass and strength of all major muscle groups. Participants exercised three times a week and received either 20 g of whey protein (n = 83) or isocaloric carbohydrate (n = 78) in liquid form immediately after each workout. Data were obtained at baseline and end point.RESULTS: The primary outcomes, lean body mass, strength and physical function increased significantly during the course of the study. Type of dietary supplementation did not influence gains in lean body mass (P = 0.365), quadriceps strength (P = 0.776) or performance during a 6-min walk (P = 0.726) or a timed up-and-go test (P = 0.151). Twenty participants discontinued the intervention.CONCLUSIONS: Ingestion of 20 g of whey protein immediately after resistance exercise three times per week, does not lead to greater gains in lean body mass, strength and physical function in elderly people with sufficient energy and protein intakes when compared to isocaloric carbohydrate.
Lean body mass (LBM) is important to maintain physical function during aging. We hypothesized that dietary protein intake and leisure-time physical activity are associated with LBM in community-dwelling older adults. To test the hypothesis, participants (n = 237; age, 65-92 years) did 3-day weighed food records and reported physical activity. Body composition was assessed using dual-energy x-ray absorptiometry. Protein intake was 0.98 ± 0.28 and 0.95 ± 0.29 g/kg body weight in male and female participants, respectively. Protein intake (in grams per kilogram of body weight) was associated with LBM (in kilograms); that is, the differences in LBM were 2.3 kg (P < .05) and 2.0 kg (P = .054) between the fourth vs the first and the fourth vs the second quartiles of protein intake, respectively. Only a minor part of this association was explained by increased energy intake, which follows an increased protein intake. Our study shows that dietary protein intake was positively associated with LBM in older adults with a mean protein intake higher than the current recommended daily allowance of 0.8 g/kg per day. Leisure-time physical activity, predominantly consisting of endurance type exercises, was not related to LBM in this group.
Objective: Increased protein intake and resistance exercise can be beneficial for maintenance of lean body mass (LBM) in older adults. However, these factors could also negatively affect renal function. We investigated changes in renal function after a 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults.Methods: Patients (N = 237, 73.7 +/- 5.7 y, 58.2% female) participated in a 12-wk resistance exercise program (3 times/wk) designed to increase strength and muscle mass of major muscle groups. Participants were randomly assigned to one of three dietary supplements consumed directly after training: whey protein drink (20 g whey protein, 20 g carbohydrates), milk protein drink (20 g milk protein, 20 g carbohydrates), or carbohydrate drink (40 g carbohydrates). Renal function was estimated as glomerular filtration rate (GFR, Cockcroft-Gault formula), and dietary intake was measured as 3-d-weighed food record at baseline and endpoint.Results: During the intervention, energy intake did not increase. Carbohydrate intake increased in the carbohydrate group and protein intake increased in the milk group, both approximately in accordance with the supplementation. In the whey group, protein intake did not increase, but carbohydrate intake did. GFR increased after the intervention (+4.4 mL/min/1.73 m(2); P < 0.001), and the changes were similar in men and women or in the age quartiles. Changes in GFR at endpoint were not associated with LBM, dietary supplements, or total protein intake.Conclusions: A 12-wk resistance exercise program combined with protein supplementation in community dwelling older adults does not negatively affect GFR. The supplementation had only minor effects on total dietary intake. (C) 2013 Elsevier Inc. All rights reserved.
BACKGROUND:Insulin is a stimulator of skeletal muscle protein anabolism and insulin resistance might therefore negatively affect muscle protein metabolism. We investigated muscle mass and physical function before and after a resistance exercise program in participants with prediabetes or type 2 diabetes mellitus (T2DM) in comparison to healthy controls.METHODS:This was a secondary analysis of a randomized controlled intervention designed to investigate resistance training among older adults. Glucose metabolism status was not a selection criteria for the trial, and group designation was done retrospectively. Participants (N = 237, 73.7 ± 5.7 y, 58.2% women) participated in a 12-week resistance exercise program (3 times/week; three sets, six to eight repetitions at 75%-80% of the one-repetition maximum), designed to increase strength and muscle mass of major muscle groups. Body composition, muscular strength, timed up and go test, 6-minute walk for distance, and blood chemical variables were measured at baseline and endpoint.RESULTS:Participants completing the study (n = 213) experienced significant changes in muscle strength or muscle function, which did not differ significantly between healthy (n = 198), prediabetic (n = 20), and T2DM participants (n = 17). Changes in serum glucose during the intervention differed by group: only glucose improved significantly in the prediabetic group, glucose and triacylglycerol improved significantly in the healthy group, whereas no serum parameter improved significantly in the T2DM group.CONCLUSIONS:A 12-week resistance exercise program improves muscle strength and muscle function to a similar extent in healthy, prediabetic, and T2DM elderly people. However, according to our data, T2DM participants do not experience favorable changes in fasting glucose or HbA(1C).
Little is known about the effects of resistance training on health related quality of life (HRQL) in the elderly.
OBJECTIVE:Prevalence of hypertension, which is the most common risk factor for cardiovascular disease in elderly people, increases with age. The aim of the study was to investigate the association between diet and blood pressure in elderly Icelanders, with focus on cod liver oil, and to compare their diet to dietary guidelines.MATERIAL AND METHODS:Diet was assessed using three-day weighed food records and blood pressure was measured after a 12-hour-fast in 236, 65-91 years old, Icelanders living in the capital area of Iceland. 99 men (42%) and 137 women (58%) participated in the study.RESULTS:According to Nordic nutrition recommendations, intake of nutrients was above lower intake levels among the majority of participants. However, 19% were under this level for vitamin-D, 13% for iodine, 17% of men for vitamin-B6, and 26% and 12% of men and women, respectively, for iron. Systolic blood pressure was inversely associated with cod liver oil intake, even when adjusted for age, body mass index, gender, and antihypertensive medications (P=0.01). Intake of long-chain omega-3 fatty acids correlated with blood pressure in a similar way. Other dietary factors were not associated with blood pressure.CONCLUSION:The results indicate that intake of cod liver oil is associated with lower blood pressure among elderly people and may therefore have beneficial effects on health. A notable proportion of participants was at risk of vitamin D, vitamin B6, iodine, and iron deficiency.
determined with high performance liquid chromatography. The nine essential amino acids and fourteen nonessential amino acids were quantified. We evaluated the minimum and maximum of amino acids retrospectively, and evaluated the prognostic factors. Results: Sixty-seven (male/female: 47/30) patients were included in this study. The age was 64.0±16.9. The focus of infection was pneumonia (33, 42.9%), gas gangrene (16, 20.8%), abdominal infection (15, 19.5%), CNS infection (6, 7.8%), infective endocarditis (1, 1.3%), and others (6, 7.8%). The whole mortality rate was 39.0%. Stepwise logistic regression revealed that the minimum of glutamate and the maximum of methionine were selected as main prognostic factors (P< 0.05). Conclusion: The altered balance of aminogram was associated with mortality in patients with sepsis. The modulation of amino acids could be the next nutritional therapy.
Background/Objectives: The aims were (1) to compare fat free mass (FFM) estimates from regional hand-held bioelectrical impedance analysis (HHBIA) with conventional BIA (CBIA) and dual energy X-ray absorptiometry (DXA) and (2) to develop a population specific equation for FFM prediction in Icelandic elderly. Subjects/Methods: DXA, CBIA and HHBIA data were available for 98 free-living Icelandic elderly (age=73.0±5.6 years, body mass index=28.8±5.2 kg/m 2 ). Participants were randomized into a development block ( n =50) and validation block ( n =48). A population specific equation for FFM prediction was calculated using CBIA-derived resistance and anthropometric data from the development block and then compared with other BIA equations (Deurenberg, Segal, company-specific equations) and DXA estimates using the validation block. Results: The correlations between BIA methods and DXA were very high, that is, >0.9; however, mean differences compared with DXA were quite variable, ranging from −5.0 (Deurenberg) to +2.5 (Segal, HHBIA) and +3.3 kg (CBIA). Mean difference of the population-specific equation was below 0.1 kg. The standard deviations of the differences ranged from 2.6 to 3.3 kg. The limits of agreement of the BIA methods were similar and between 9.9 and 12.9 kg. Conclusions: In Icelandic elderly, HHBIA and CBIA produce similar FFM estimates when using company-specific prediction equations. CBIA provides the additional possibility to use a population-specific prediction equation, which yields best results. However, limits of agreement were wide and similar of all employed BIA methods, which indicates principal limitations of BIA analysis in the determination of FFM.
Meat and meat products are of high nutritional value; however, they frequently provide salt and fat in high amounts, which can have negative health effects when consumed in excess. We investigated salt- and fat-reduced meat products, i.e. sensory evaluation and consumer surveys were carried out as well as a dietary intervention study was carried out in overweight individuals who used salt- and fat-reduced products as a part of an energy-restricted diet. Although differences were detected in the sensory evaluation between reduced and regular meat products, the participants in the consumer surveys and in the dietary intervention study gave good ratings for the fat and fat-reduced meat products. The intervention study led to weight loss and improved cardiovascular risk, but did not reveal side effects associated with the consumption of these products. Our study indicates that such products are well accepted by potential consumers and can be included successfully in a weight loss programme.
Background/Aim: Leptin plays an important role in energy metabolism. The primary objective of the study was to investigate whether baseline leptin levels predict weight loss during a dietary intervention in overweight and obese individuals. Methods: A total of 324 individuals (138 men and 186 women, aged 20–40 years, BMI 27.5–32.5) were recruited in Iceland, Ireland and Spain. The intervention lasted for 8 consecutive weeks, and subjects were instructed to follow a diet, energy restricted by 30%. Anthropometric variables were assessed before and after the intervention. Leptin concentration was measured at baseline and corrected for fat mass. Linear models were used to find out which variables predicted weight loss. Results: At end point, significant weight loss was observed (5.16 ± 3.06 kg, p < 0.001). High baseline leptin concentrations were a significant negative predictor of weight loss in men (p = 0.028), with a predicted difference of 1.8 kg between the lowest and highest leptin quartile. Conclusion: Our study underlines the importance of leptin in energy metabolism. Plasma leptin concentrations at baseline are a predictor of weight loss in overweight men after an 8-week dietary intervention. The same effect was not observed in overweight women, which suggests that the role of leptin in the regulation of weight is gender specific.