Norwegian adolescents with asthma are physical active and fit*

Background: Evidence regarding habitual physical activity levels and aerobic fitness of asthmatic compared to nonasthmatic children and adolescents is contradictory, and it is unclear if low physical activity levels can contribute to asthma development. The present study therefore aimed to determine whether adolescents with asthma have reduced physical activity levels and aerobic fitness, or increased energy intake and body fat compared to controls. Methods: From the environment and childhood asthma study in Oslo, 174 (13‐ to 14‐year old) adolescents, 95 (66 boys) with and 79 (41 boys) without asthma performed maximal running on a treadmill with oxygen consumption measurement (aerobic fitness) and had the sum of four skinfolds and waist circumference recorded (body fat), followed by wearing an activity monitor and registering diet for four consecutive days. Asthma was defined by at least two of the following three criteria fulfilled: (1) dyspnoea, chest tightness and/or wheezing; (2) a doctor’s diagnosis of asthma; (3) use of asthma medication. Participants with asthma used their regular medications. Results: Neither aerobic fitness, total energy expenditure nor hours in moderate to very vigorous intensity physical activity during week and weekend differed between adolescents with and without asthma. Energy intake and body fat was similar in both groups. Conclusions: Total energy expenditure, aerobic fitness and hours in moderate to very vigorous intensity physical activity were not reduced and energy intake and body fat measured with skinfolds not increased among Norwegian adolescents with asthma.     

Exercise,Fitness, and Neurocognitive Function in Older Adults: The “Selective Improvement” and “Cardiovascular Fitness” Hypotheses

Background   Although basic research has uncovered biological mechanisms by which exercise could maintain and enhance adult brain health, experimental human studies with older adults have produced equivocal results. Purpose   This randomized clinical trial aimed to investigate the hypotheses that (a) the effects of exercise training on the performance of neurocognitive tasks in older adults is selective, influencing mainly tasks with a substantial executive control component and (b) performance in neurocognitive tasks is related to cardiorespiratory fitness. Methods   Fifty-seven older adults (65–79 years) participated in aerobic or strength-and-flexibility exercise training for 10 months. Neurocognitive tasks were selected to reflect a range from little (e.g., simple reaction time) to substantial (i.e., Stroop Word–Color conflict) executive control. Results   Performance in tasks requiring little executive control was unaffected by participating in aerobic exercise. Improvements in Stroop Word–Color task performance were found only for the aerobic exercise group. Changes in aerobic fitness were unrelated to changes in neurocognitive function. Conclusions   Aerobic exercise in older adults can have a beneficial effect on the performance of speeded tasks that rely heavily on executive control. Improvements in aerobic fitness do not appear to be a prerequisite for this beneficial effect.

Influence of hand cycling on physical capacity in the rehabilitation of persons with a spinal cord injury: a longitudinal cohort study

Valent LJ, Dallmeijer AJ, Houdijk H, Slootman HJ, Post MW, van der Woude LH. Influence of hand cycling on physical capacity in the rehabilitation of persons with a spinal cord injury: a longitudinal cohort study.

Objective

To investigate the influence of hand cycling on outcome measures of physical capacity during and after rehabilitation in persons with paraplegia and tetraplegia in The Netherlands.

Design

A longitudinal cohort study with measurement moments at the start (t1) and end (t2) of clinical rehabilitation and 1 year after discharge (t3). Hand cycle use was assessed by means of questionnaires at t2 and t3.

Setting

Eight rehabilitation centers in The Netherlands.

Participants

Subjects (N=162) with a recent spinal cord injury.

Interventions

All subjects followed the regular rehabilitation program.

Main Outcome Measures

Peak oxygen uptake (Vo₂peak) and peak power output (POpeak) determined in a handrim wheelchair peak exercise test, peak muscle strength of the upper extremities, and pulmonary function.

Results

A significantly larger increment in Vo₂peak, POpeak, and elbow extension strength was found in subjects with paraplegia during clinical rehabilitation. No such effect was found in subjects with tetraplegia. In the postrehabilitation period, no influence of hand cycling on any outcome measure was found in subjects with paraplegia or subjects with tetraplegia.

Conclusions

After correction for baseline values and confounders, regular hand cycling (once a week or more) appeared to be beneficial for improving aerobic physical capacity in persons with paraplegia during clinical rehabilitation. The small and heterogeneous study groups may have hampered the finding of positive results of hand cycling in persons with tetraplegia.     

Self-guided brisk walking training with or without poles: a randomized-controlled trial in middle-aged women

Walking with poles (Nordic walking, NW) has become popular. We compared training responses of brisk walking (W) or NW on cardiorespiratory and neuromuscular fitness. We randomized 121 non-obese sedentary women (aged 50-60) to an NW or W group (NWG, WG), to train 40 min four times weekly for 13 weeks. Intensity was based on subjective perception of exertion. Cardiorespiratory performance was assessed in four levels corresponding to 50%, 65%, 80% and 100% of peak VO(2). Fifty-four NWG and 53 WG subjects completed the study. The mean intensity was about 50% of heart rate (HR) reserve. The baseline peak VO(2) was 25.8 (SD 3.9) mL/min/kg. Both groups improved peak VO(2) similarly (NWG 2.5 mL/min/kg, 95% confidence interval (CI) 1.9-3.3; WG 2.6, CI 1.9-3.3). In the submaximal stages while walking with or without poles, HR and lactate decreased after training in both groups, but the changes were not statistically significantly different between the groups. Of the neuromuscular tests after training, the only significant difference between the groups was in the leg strength in the one-leg squat, favoring WG. In conclusion, both training modes improved similarly health-enhancing physical fitness, and they were feasible and safe.     

Secular trends in cardiorespiratory fitness and body mass index in Danish children: The European Youth Heart Study

AIM: To examine the secular trends in cardiorespiratory fitness (CF) and body fatness in Danish children. Trends were analyzed overall and across socioeconomic status (SES). METHODS: Two cross-sectional studies conducted on 589 and 458 third-grade Danish children in 1997-1998 and 2003-2004, respectively. CF was determined by a maximal cycle-ergometer test. The lowest sex-specific quartile of CF in the study from 1997 to 1998 was used as a cut-point for low CF. Body mass index (BMI) cut-points were used to describe overweight, and SES was divided into two groups according to parents' occupation. RESULTS: This study showed a secular decline in CF in girls overall. Increased CF, BMI, and prevalence of overweight were observed in boys with high SES, in boys with low SES, and in girls with low SES, respectively. However, after additional Bonferroni's correction, none of the statistical analyses performed across socioeconomic gradients reached significant P-values. CONCLUSION: CF declined in girls overall. Although not statistically significant after additional Bonferroni's correction, results in general showed less favorable trends in low SES children. Thus, trying to describe secular trends in CF and body fatness overall without any regard to SES might disguise social-caused differences. However, further studies are needed in order to verify this hypothesis.     

Inhibitors of the Hepatitis C Virus RNA-Dependent RNA Polymerase NS5B

More than 20 years after the identification of the hepatitis C virus (HCV) as a novel human pathogen, the only approved treatment remains a combination of pegylated interferon-α and ribavirin. This rather non-specific therapy is associated with severe side effects and by far not everyone benefits from treatment. Recently, progress has been made in the development of specifically targeted antiviral therapy for HCV (STAT-C). A major target for such direct acting antivirals (DAAs) is the HCV RNA-dependent RNA polymerase or non-structural protein 5B (NS5B), which is essential for viral replication. This review will examine the current state of development of inhibitors targeting the polymerase and issues such as the emergence of antiviral resistance during treatment, as well as strategies to address this problem.     

Profile of Patients at Admission into an Inpatient Stroke Rehabilitation Programme: Cardiorespiratory Fitness and Functional Characteristics

Purpose:

The purposes of this study were to characterize the cardiorespiratory capacity of individuals on admission to inpatient rehabilitation following stroke and to examine the relationship between measures of cardiorespiratory capacity and standard indices of neurological deficit and functional status.

Methods:

We recruited 45 patients within the first 10 days of admission to rehabilitation. We performed measures of aerobic fitness (VO₂peak), functional status (Functional Independence Measure [FIM] and Clinical Outcomes Variable Score [COVS]), and neurological deficit (National Institutes of Health Stroke Scale [NIHSS] and Chedoke-McMaster Stroke Assessment scale [CMSA]).

Results:

Nineteen women and 26 men with a mean (SD) age of 65.2 (14.5) years were admitted to rehabilitation 16.2 (11.9) (minimum 3, maximum 62) days post-stroke. Average VO₂peak was less than half the value expected in age-matched healthy individuals at 11.1 (3.1) ml/kg/min. The associations between VO₂peak and FIM, NIHSS, and COVS were weak (r = 0.25, -0.12, and 0.26 respectively, p = 0.12, 0.46, and 0.10 respectively). There were no differences in VO₂peak in higher-functioning individuals with CMSA leg scores of 5 and 6 compared to lower-functioning individuals with scores of 3 and 4 (p = 0.30).

Conclusion:

Cardiorespiratory capacity is extremely low in individuals during the first 3 months after stroke. Alternative measures of functional or clinical status do not adequately reflect this cardiorespiratory state; thus, routine measurement of cardiorespiratory capacity should be considered, along with a risk-factor profile.     

The impact of the ILCOR 2005 CPR guidelines on a physical fitness assessment: a comparison of old and new protocols

OBJECTIVE: St. John Ambulance Australia has used the performance of CPR for 10 min as a fitness test for its members. Recent changes in international guidelines for cardiopulmonary resuscitation caused concern that the new ILCOR protocol was more strenuous than the previous one. This study compared the two protocols to determine if there were significant differences and to allow an evidence-based decision on the continuation or modification of this practice. MATERIALS AND METHODS: We studied 26 subjects performing single-rescuer cardiopulmonary resuscitation on a manikin. Every subject did 10 min cardiopulmonary resuscitation using each protocol. The study used a randomized cross-over design. The estimated maximum heart rate was calculated for each subject. Compression rate and effective ventilation (number and depth) were enforced by direct feedback. Subjective and objective measures of physical activity were recorded at regular intervals. RESULTS: The maximum percentage of estimated maximum heart rate achieved during 15:2 and 30:2 CPR was 76+/-2% and 79+/-2%, respectively (mean+/-standard error of mean; P<0.001). The rate pressure product at the end of 10 min cardiopulmonary resuscitation was 18,999+/-891 for 15:2 and 19,204+/-757 for 30:2 (ns) while the Borg rating of perceived exertion was 13.7+/-0.5 for 15:2 and 14.8+/-0.5 for 30:2 (P<0.05). CONCLUSION: The new protocol increases both objective and subjective measures of effort. While the absolute differences in workload are small, they are statistically significant. There are significant indicators of this difference in the first 3 min of assessment. Rescuers are more likely to be operating at a high-level of physical activity. To avoid increasing the demands of its mandatory fitness test, St. John should reduce the required performance time from its present 10 min.     

Association of blood pressure and fitness with levels of atherosclerotic risk markers pre-exercise and post-exercise

BACKGROUND: Physical fitness may attenuate the increased atherosclerotic risk in patients with systemic hypertension. We investigated the association of screening blood pressure (BP) and cardiorespiratory fitness with baseline levels and exercise-induced changes in levels of soluble atherosclerotic risk markers. METHODS: Twenty-six otherwise healthy and unmedicated subjects with elevated BP (systolic BP and/or diastolic BP > or =130/85 mm Hg) and 40 subjects with normal BP underwent 20-min treadmill exercise at 65% to 70% of predetermined peak oxygen consumption (VO(2peak)). Interleukin (IL)-6, soluble intercellular adhesion molecule (sICAM)-1, von Willebrand factor (VWF) antigen, and plasminogen activator inhibitor (PAI)-1 antigen were measured at baseline (ie, pre-exercise), early postexercise, and late postexercise (ie, 25 min after exercise). RESULTS: At baseline, higher screening mean arterial BP (MAP) independently predicted higher sICAM-1 levels (P = .031), and lower VO(2peak) independently predicted higher IL-6 (P = .016) and PAI-1 (P < .001) levels. Early and late postexercise lower VO(2peak) was associated with higher mean PAI-1 (P < or = .072) and IL-6 (P < or = .026) levels, and higher screening MAP was associated with higher mean sICAM-1 levels (P < or = .035). Higher VO(2peak) was associated with a greater PAI-1 increase from baseline to early postexercise in subjects with elevated BP (P = .045) but not in those with normal BP. CONCLUSIONS: Circulating levels of some atherosclerotic risk markers at baseline and with exercise were higher with elevated BP and lower with better fitness. Greater fitness did not particularly protect subjects with elevated BP from potentially harmful responses of atherosclerotic risk markers to acute physical exercise.     

Effect of <Emphasis Type="SmallCaps">L</Emphasis>-carnitine on the physical fitness of thalassemic patients

Poor physical fitness is a common problem among thalassemic patients. l-Carnitine plays an essential role in fatty acid β-oxidation, a process especially important in the organs that preferentially use fatty acid as a source of energy such as the myocardium and the skeletal muscles. The main objective of this study is to assess the effect of the administration of oral l-carnitine on exercise tolerance and physical fitness in patients with thalassemia major. Thirty patients followed up at the New Cairo University Children Hospital were included in this study. Clinical, laboratory, and cardiopulmonary exercise testing were performed before and after 6 months of oral l-carnitine therapy (50 mg/kg/day). The oxygen consumption, cardiac output, and oxygen pulse at maximal exercise significantly increased after l-carnitine therapy (p<0.001, p=0.002 and p<0.001, respectively). However, there was no significant change in minute ventilation and ventilatory equivalent of carbon dioxide (p=0.07 and p=0.06, respectively). A weak but positive correlation between the age of the patients and the degree of improvement in exercise parameters was noted. There was also significant increase in the blood transfusion intervals after l-carnitine administration (p=0.008). However, there was no significant change in hemoglobin concentration (p=0.4). l-Carnitine seems to be a safe and effective adjunctive therapeutic approach in thalassemic patients. It improves their cardiac performance and physical fitness. The younger the patients are, the higher is the degree of improvement in their exercise parameters.