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Examines the feasibility of a power-type strength training program for middle aged men and women. Impact of the training program on perceived health and fitness and on knee and low back symptoms; Rate of exercise-induced injuries; Significance to studies of sports medicine.

In diabetes, the endogenous defence systems are overwhelmed, causing various types of stress in tissues. In this study, newly diagnosed or diet-treated type 2 diabetics (T2D) (n = 10) were compared with subjects with impaired glucose tolerance (IGT) (n = 8). In both groups, at resting conditions, blood samples were drawn for assessing metabolic indices and skeletal muscle samples (m. vastus lateralis)were taken for the measurements of cellular defencemarkers: thioredoxin-1 (TRX-1) and stress proteins HSP72, HSP90. The protein level of TRX-1 was 36.1% lower (P = 0.031) and HSP90 was 380% higher (P < 0.001) in the T2D than in the IGT subjects, with no significant changes in HSP72. However, after the adjustment of both analyses with HOMA-IR only HSP90 difference remained significant. In conclusion, level of TRX-1 in skeletal muscle tissue was lower while that of HSP90 was higher in T2D than in IGT subjects. This may impair antioxidant defence and lead to disruptions of protein homoeostasis and redox regulation of cellular defences. Because HSP90 may be involved in sustaining functional insulin signalling pathway in type 2 diabetic muscles and higher HSP90 levels can be a consequence of type 2 diabetes, our results are potentially important for the diabetes research. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate and compare the effects of training either with a light load or without any load in a 16-week power-type strength training intervention in sedentary middle-aged subjects. A total of 85 subjects participated in the study. In a supervised 22-week training intervention, including 16 weeks of power-type strength training, 42 subjects (Light Load group = LL group) trained with a 1.1 kg weight on each ankle and 43 subjects (No Load group = NOL group) trained without any external load. Subjects were comparable concerning their training attendance, and anthropometric and physiological characteristics. Training effects were evaluated by measuring Vertical Squat Jump (VSJ), 20-metre Running Time (20 mRT), Maximal Anaerobic Cycling Power of leg muscles (MACP), and Maximal Oxygen Uptake (VO2max) before and after the intervention. The LL group improved VSJ and MACP significantly (p<0.05), com- pared with the NOL group. No difference between the groups was observed in 20 mRT or in VO2max. To conclude, the external loads of 2.2 kg, in total, increased the efficiency of power-type strength training in vertical jumps and in anaerobic power in leg muscles, but not in sprint running. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to examine exercise capacity and its relationship to neurological disability as measured using the Expanded Disability Status Scale (EDSS) and to leisure physical activity in subjects with multiple sclerosis (MS). Thirty-four men and 61 women (mean age 44 ±6.7 years, mean disease duration 5.7 ±6.4 years) with mild to moderate disability (EDSS range l.0-5.5) participated. They underwent an incremental exercise test on a leg cycling ergometer. Leisure physical activity was measured using a questionnaire. Peak oxygen uptake (VO 2peak) in men was 27.0±5.2 mL/kg/min, and in women 21.7 ±5.5 mL/kg/min. The disability correlated inversely with the VO 2peak both in men (r = -0.50, P =0.004) and in women (r = -0.25, P =0.05). No correlation between disease duration and VO 2peak was found. In a multivariate regression analysis, neurological disability was confirmed as a predictor of VO 2peak. No evidence of a relationship between leisure physical activity and VO 2peak was found. A main finding was that disability and exercise capacity are inter-related, even in subjects who are not severely handicapped (84% had an EDSS of < 4.0). The level of disability should be taken into account in the planning of aerobic exercise programs for fully ambulatory MS subjects. [ABSTRACT FROM AUTHOR]

Objectives: Accumulation of intra-abdominal fat has been suggested, but not yet proved, to be basically as a result of chronic psychosocial stress causing arousal of hypothalamic-pituitary-adrenal cortex axis. Our objectives were to study the association between psychosocial stress, obesity and body fat distribution when genetic factors are identical.Design: Monozygotic twins discordant for obesity were examined in an in-patient setting.Subjects: Adult monozygotic twin pairs (12 female, 8 male) with an average intrapair difference of 17 kg in body weight. They were divided into two groups: in group A the visceral fat area of the obese cotwin was higher and, in group B, lower than the gender-specific median value.Main Measures: Hormonal, physiological and psychological distress indicators, and sleep measures.Results: Daily urinary cortisol and noradrenaline excretion were higher in the obese cotwins when compared with the nonobese cotwins in group A but not in group B (P=0.026 and 0.020 when intrapair differences were compared between groups A and B, respectively). In serum cortisol, ACTH and CBG concentrations a similar trend was not statistically significant. In group A, the obese cotwins consumed almost 2.5 times as much alcohol as their lean cotwins, whilst in group B the situation was the opposite. The mean amount of active sleep was significantly higher and that of quiet sleep significantly lower in the obese than the lean cotwins only in group A. Intrapair differences in emotional reactions indicating distress and lack of subjective energy were seen only in group A.Conclusion: When genetic factors are identical, visceral fat accumulation, rather than obesity in general, is associated with increased psychosocial stress and concomitant hormonal changes. [ABSTRACT FROM AUTHOR]

Isoresistive trunk muscle dynamometer is a potentially useful piece of equipment in evaluation of trunk muscle velocity, but to date, studies analysing the possibilities and limitations of such measurements are scarce. The aim of this study was to analyse the trunk muscle velocity in repetitive flexion and extension movements at three different angular phases, using an isoresistive trunk muscle dynamometer, and to assess the reliability of the measurements. The study population consisted of 120 healthy, sedentary men and women who volunteered for the study. The measurements were carried out before and after a 22-week training intervention programme. The results show that the peak velocities of the phases between 15 and 35° in flexion and 20–0° in extension (i.e. the second phases) correlated highly (r=0·99 in flexion and in extension) with the peak velocity of the whole movement ranging from -5 to 55° in flexion and 40 to -20° in extension. Correlations were high, both before and after the intervention. The LISREL model analysis showed high reliability of measurement for the second angular phases (in flexion and extension). According to the model, the correlation between the first and second measurement (with a 22-week training intervention in between) was 0·78 in flexion and 0·81 in extension. In conclusion, the angular phases from 15 to 35° in flexion and from 20 to 0° in extension represent the peak velocity of the whole movement. Negative residual correlations between the first and last angular phases in the LISREL model reflect the way of performing the movement: the faster the start the slower the end, and vice versa. [ABSTRACT FROM AUTHOR]

The aim of this cross-sectional study was to compare mobility and muscle strength in male former elite endurance and power athletes aged 66−91 years ( n = 150; 50 men in both former elite athlete groups and in their control group). Agility, dynamic balance, walking speed, chair stand, self-rated balance confidence ( ABC-scale), jumping height, and handgrip strength were assessed. Former elite power athletes had better agility performance time than the controls (age- and body mass index, BMI-adjusted mean difference −3.6 s; 95% CI −6.3, −0.8). Adjustment for current leisure time physical activity ( LTPA) and prevalence of diseases made this difference non-significant ( P = 0.214). The subjects in the power sports group jumped higher than the men in the control group (age- and BMI-adjusted mean differences for vertical squat jump, VSJ 4.4 cm; 95% CI 2.0, 6.8; for countermovement jump, CMJ 4.0 cm; 95% CI 1.7, 6.4). Taking current LTPA and chronic diseases for adjusting process did not improve explorative power of the model. No significant differences between the groups were found in the performances evaluating dynamic balance, walking speed, chair stand, ABC-scale, or handgrip strength. In conclusion, power athletes among the aged former elite sportsmen had greater explosive force production in their lower extremities than the men in the control group. [ABSTRACT FROM AUTHOR]

In randomized controlled trials ( RCTs), with customized structured physical exercise activity ( SPEA) interventions, the dose of leisure-time physical activity ( LTPA) should exceed the LTPA dose of the nonexercising control ( C) group. This increase is required to substantiate health improvements achievable by exercise. We aimed to compare the dose of SPEA, LTPA, and total LTPA ( SPEA + LTPA) between a randomized Nordic walking ( NW) group, a power-type resistance training ( RT) group, and a C group during a 12-week exercise intervention in obese middle-aged men ( n = 144) with impaired glucose regulation. The dose of physical activity was measured with diaries using metabolic equivalents. No significant difference ( P > 0.107) between the groups was found in volume of total LTPA. The volume of LTPA was, however, significantly higher ( P < 0.050) in the C group than in the NW group, but not compared with the RT group. These results indicate that structured exercise does not automatically increase the total LTPA level, possibly, as a result of compensation of LTPA with structured exercise or spontaneous activation of the C group. Thus, the dose of total LTPA and the possible changes in spontaneous LTPA should be taken into account when implementing a RCT design with exercise intervention. [ABSTRACT FROM AUTHOR]

Aims The aim of this study was to investigate the prevalence of cardiovascular autonomic neuropathy in persons with previously diagnosed impaired glucose tolerance and to characterize associations between components of metabolic syndrome and cardiovascular autonomic neuropathy in the Finnish Diabetes Prevention Study cohort. Methods Two hundred and sixty-eight individuals with impaired glucose tolerance at baseline in the Finnish Diabetes Prevention Study, but not diagnosed with diabetes during follow-up,were studied for cardiovascular autonomic neuropathy. At the second annual follow-up visit after the end of lifestyle intervention,we performed deep-breathing and active orthostatic tests to detect possible parasympathetic and sympathetic dysfunction. To describe metabolic characteristics, anthropometric measurements, an oral glucose tolerance test and assessments for HbA1c, serum lipids and blood pressure were carried out. Results Prevalence of parasympathetic dysfunction was 25% and prevalence of sympathetic dysfunction was 6%, with no difference between the former intervention and control group participants or between men and women. Subjects with parasympathetic dysfunction were older, more obese (weight,waist circumference, body mass index) and had higher triglyceride concentration compared with those with normal parasympathetic function (P < 0.01 for all). Parasympathetic dysfunction was not significantly associated with other characteristics of metabolic syndrome; for example, high cholesterol, glucose and insulin levels or HbA1c. Correlations between the Expiration/Inspiration (E/I) ratio (the longest heart beat duration in expiration divided by the shortest heart beat duration in inspiration) and measures reflecting obesity were statistically significant in the pooled population and in men but not in women. Conclusions Cardiovascular autonomic neuropathy is common in persons with impaired glucose tolerance. Obesity, especially among men, seems to play an important role in the early pathogenesis of cardiovascular autonomic neuropathy. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the influence of positive family history (FH+) of diabetes and 19 known genetic risk loci on the effectiveness of lifestyle changes and their predictive value on the incidence of type 2 diabetes in the Finnish Diabetes Prevention Study (DPS).Research Design and Methods: A total of 522 subjects with impaired glucose tolerance (IGT) were randomized into the control (n = 257) and intervention (n = 265) groups. The mean follow-up was 6.2 years (median 7 years), and the lifestyle intervention, aimed at weight reduction, healthy diet, and increased physical activity, lasted for 4 years (range 1-6 years). An oral glucose tolerance test (OGTT) and assessment of basic clinical variables were performed annually.Results: The effect of intervention on the incidence of diabetes was almost similar in subjects with FH+ compared with subjects with a negative family history (FH-) of diabetes during the entire follow-up. In the Cox model, including FH, genetic risk SNPs, and randomization group, and adjusted for the effects of age, sex, BMI, and study center, only lifestyle intervention had a significant effect (hazard ratio 0.55, 95% CI 0.41-0.75, P < 0.001) on the incidence of diabetes. Further analyses showed that in addition to the baseline glucose and insulin values, 1-year changes in 2-h glucose and 2-h insulin achieved by lifestyle intervention had a significant effect on the incidence of diabetes.Conclusions: These results emphasize the effectiveness of lifestyle intervention in reducing the risk of diabetes in high-risk individuals independently of genetic or familial risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Aims we analysed the Finnish Diabetes Prevention Study data in order to evaluate how the new HbA1c-based criterion compares with the oral glucose tolerance test in diagnosing Type 2 diabetes among high-risk individuals during a prospective average follow-up of 4 years. Methods In the Diabetes Prevention Study, 172 men and 350 women who were overweight and had impaired glucose tolerance at baseline were randomized into an intensive lifestyle intervention or a control group. The oral glucose tolerance test and HbA1c measurements were performed annually until the diagnosis of diabetes using the World Health Organization 1985 criteria. Results The sensitivity of the HbA1c ≥ 6.5%(≥ 48 mmol/ mol) as a diagnostic criterion for Type 2 diabetes was35%(95%CI 24%, 47%) in women and 47% (95% CI 31%, 64%) in men compared with diagnosis based on two consecutive oral glucose tolerance tests. The corresponding sensitivities for HbA1c ≥ 6.0% (≥ 42 mmol/ mol)were 67%(95% CI 55%, 77%) and 68% (95% CI 51%, 82%). The participants with HbA1c ≥ 6.5% (≥ 48 mmol/ mol) and diabetes based on the oral glucose tolerance test were more obese and had higher fasting glucose and 2-h glucose concentrations than those who had a diabetic oral glucose tolerance test but HbA1c< 6.5%(< 48 mmol/mol). There were no differences in the predictive performance of baseline fasting glucose, oral glucose tolerance test and HbA1c. Conclusions Of those with diabetes diagnosis based on two oral glucose tolerance tests during the Diabetes Prevention Study follow-up, 60% would have remained undiagnosed if diagnosis had been based onHbA1c ≥ 6.5%(≥ 48 mmol/ mol) criterion. [ABSTRACT FROM AUTHOR]

Objective: Both short and long sleep duration have frequently been found to be associated with an increased risk for diabetes. The aim of the present exploratory analysis was to examine the association between sleep duration and type 2 diabetes after lifestyle intervention in overweight individuals with impaired glucose tolerance in a 7-year prospective follow-up.Research Design and Methods: A total of 522 individuals (aged 40-64 years) were randomly allocated either to an intensive diet-exercise counseling group or to a control group. Diabetes incidence during follow-up was calculated according to sleep duration at baseline. Sleep duration was obtained for a 24-h period. Physical activity, dietary intakes, body weight, and immune mediators (C-reactive protein and interleukin-6) were measured.Results: Interaction between sleep duration and treatment group was statistically significant (P = 0.003). In the control group, the adjusted hazard ratios (HRs) (95% CI) for diabetes were 2.29 (1.38-3.80) and 2.74 (1.67-4.50) in the sleep duration groups 9-9.5 h and >or=10 h, respectively, compared with for that of the 7-8.5 h group. In contrast, sleep duration did not influence the incidence of diabetes in the intervention group; for sleep duration groups 9-9.5 h and >or=10 h, the adjusted HRs (95% CI) were 1.10 (0.60-2.01) and 0.73 (0.34-1.56), respectively, compared with that in the reference group (7-8.5 h sleep). Lifestyle intervention resulted in similar improvement in body weight, insulin sensitivity, and immune mediator levels regardless of sleep duration.Conclusions: Long sleep duration is associated with increased type 2 diabetes risk. Lifestyle intervention with the aim of weight reduction, healthy diet, and increased physical activity may ameliorate some of this excess risk. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the role of skeletal muscle fibre type in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance (IGT) during a 2-year exercise and dietary intervention. Methods: Muscle biopsies (musculus vastus lateralis) were taken from 22 subjects belonging to the intervention group of the Finnish Diabetes Prevention Study [ 1 ]. According to their myosin heavy chain (MHC) profile at the baseline, the subjects were divided into two groups: IGTslow (n = 10) with a high proportion of MHC I isoforms and IGTfast (n = 12) with a high proportion of MHC II isoforms in the vastus lateralis muscle. The intervention consisted of dietary counselling, strength and power training and/or aerobic exercise. The amount of exercise was the same in both groups; the exercise frequency was 5.1 ± 2.7 h/week in the IGTslow and 5.1 ± 2.8 h/week in the IGTfast group. Results: Fasting glucose (p < 0.05), 2-h glucose (p < 0.05), fasting insulin (p < 0.05), haemoglobin A1c (HbA1c) (p < 0.01) and insulin resistance (p < 0.05) [homeostasis model assessment for insulin resistance (HOMA-IR)] decreased in the IGTfast group, whereas only the 2-h glucose and HbA1c concentrations decreased in the IGTslow group. The amount of the glycogen synthase kinase-3-αβ (GSK-3-αβ) decreased in the IGTfast group (p < 0.05). Exercise training increased the lactate dehydrogenase (LDH) (p < 0.01), LDH-1 (p < 0.05) and citrate synthase (CS) (p < 0.05) activities in the vastus lateralis muscle in the IGTslow group, but only the CS activity (p < 0.05) in the IGTfast group. Conclusions: The glucose metabolism improved both in the IGTslow and IGTfast group during the 2-year exercise and dietary intervention. The change was more prominent in the IGTfast group than in the IGTslow group, associated with the decrease of the GSK-αβ protein expression in skeletal muscle. The exercise training improved both glycolytic and oxidative capacity in the vastus lateralis muscle. The glycolytic capacity improved in the IGTslow group and the oxidative capacity in both groups. [ABSTRACT FROM AUTHOR]

Clinical trials have demonstrated that lifestyle changes can prevent type 2 diabetes, but the importance of leisure-time physical activity (LTPA) is still unclear. We carried out post hoc analyses on the role of LTPA in preventing type 2 diabetes in 487 men and women with impaired glucose tolerance who had completed 12-month LTPA questionnaires. The subjects were participants in the Finnish Diabetes Prevention Study, a randomized controlled trial of lifestyle changes including diet, weight loss, and LTPA. There were 107 new cases of diabetes during the 4.1-year follow-up period. Individuals who increased moderate-to-vigorous LTPA or strenuous, structured LTPA the most were 63-65% less likely to develop diabetes. Adjustment for changes in diet and body weight during the study attenuated the association somewhat (upper versus lower third: moderate-to-vigorous LTPA, relative risk 0.51, 95% CI 0.26-0.97; strenuous, structured LTPA, 0.63, 0.35-1.13). Low-intensity and lifestyle LTPA and walking also conferred benefits, consistent with the finding that the change in total LTPA (upper versus lower third: 0.34, 0.19-0.62) was the most strongly associated with incident diabetes. Thus increasing physical activity may substantially reduce the incidence of type 2 diabetes in high-risk individuals. [ABSTRACT FROM AUTHOR]