Late health outcomes in survivors of Wilms tumor: A report from the St. Jude Lifetime (SJLIFE) cohort study.

10038 Background: We aimed to characterize late health, neurocognitive, and physical performance outcomes among survivors of Wilms tumor. Methods: Wilms tumor survivors (n = 280), ≥ 5 years from diagnosis, participating in SJLIFE were clinically assessed along with a community control sample (n = 625). Health outcomes were graded per a modified Common Terminology Criteria for Adverse Events (grade 1 [mild] to grade 4 [life threatening]). Standardized neurocognitive testing was graded using age-adjusted z-scores. Aerobic function (six-minute walk), mobility (timed up and go) and flexibility (sit and reach) were assessed. Associations between treatment exposures and prevalent conditions were examined by multivariable logistic regression, adjusted for current age, sex and race. Results: Survivors (59% female, 73% white), median age 3 years (range 0-15) at diagnosis and 31 years (9-58) at evaluation, were comprehensively evaluated on the St. Jude campus. Two-thirds (67%) were treated with doxorubicin (median dose 175 mg/m2 range 52-490), 167 (60%) received abdominal radiation (median dose 12 Gy range 8.8-61.2) and 25% received chest radiation (12 Gy range 9-44). By age 40 years, survivors averaged 12.7 (95% confidence interval [CI] 11.7-13.8) grade 1-4 and 7.5 (CI 6.7-8.2) grade 2-4 conditions, compared to 4.2 (CI 3.9-4.6) and 2.3 (CI 2.1-2.5), respectively, among controls. The most prevalent medical conditions (grade ≥ 2) are reported in the table. Abnormal glucose metabolism was associated with abdominal radiation (relative risk [RR] 5.1 CI 1.4-19.0); restrictive pulmonary defects with chest radiation (RR 24.0 CI 3.2-180); and cardiomyopathy (RR 15.6 CI 1.9-128), pulmonary diffusion (RR 4.5 CI 1.3-15.1), and chronic kidney disease (RR 4.5 CI 1.3-16.1) with doxorubicin exposure. Survivors had a three-fold higher risk (standardized incidence ratio 3.5, CI 2.2-6.6) for subsequent neoplasms. Impairments (grade ≥ 2) in executive function (20% vs. 12%), attention (17% vs. 9%), memory (21% vs. 10%), and processing speed (20% vs. 8%) were more frequent in survivors than controls (p < 0.05). Impairments in aerobic function (13.6%), mobility (13.6%), and flexibility (11.1%) were higher than expected (p < 0.01). Significant associations were not identified between treatment exposures and neurocognitive or physical performance outcomes. Conclusions: Systematic clinical assessment identified a significant burden of chronic health conditions and previously unrecognized neurocognitive and physical performance limitations in survivors of Wilms tumor.[Table: see text]

Interlimb differences in parameters of aerobic function and local profiles of deoxygenation during double-leg and counterweighted single-leg cycling

It is typically assumed that in the context of double-leg cycling, dominant (DOMLEG) and nondominant legs (NDOMLEG) have similar aerobic capacity and both contribute equally to the whole body physiological responses. However, there is a paucity of studies that have systematically investigated maximal and submaximal aerobic performance and characterized the profiles of local muscle deoxygenation in relation to leg dominance. Using counterweighted single-leg cycling, this study explored whether peak O2 consumption (V̇o2peak), maximal lactate steady-state (MLSSp), and profiles of local deoxygenation [HHb] would be different in the DOMLEG compared with the NDOMLEG. Twelve participants performed a series of double-leg and counterweighted single-leg DOMLEG and NDOMLEG ramp-exercise tests and 30-min constant-load trials. V̇o2peak was greater in the DOMLEG than in the NDOMLEG (2.87 ± 0.42 vs. 2.70 ± 0.39 L/min, P < 0.05). The difference in V̇o2peak persisted even after accounting for lean mass ( P < 0.05). Similarly, MLSSp was greater in the DOMLEG than in the NDOMLEG (118 ± 31 vs. 109 ± 31 W; P < 0.05). Furthermore, the amplitude of the [HHb] signal during ramp exercise was larger in the DOMLEG than in the NDOMLEG during both double-leg (26.0 ± 8.4 vs. 20.2 ± 8.8 µM, P < 0.05) and counterweighted single-leg cycling (18.5 ± 7.9 vs. 14.9 ± 7.5 µM, P < 0.05). Additionally, the amplitudes of the [HHb] signal were highly to moderately correlated with the mode-specific V̇o2peak values (ranging from 0.91 to 0.54). These findings showed in a group of young men that maximal and submaximal aerobic capacities were greater in the DOMLEG than in the NDOMLEG and that superior peripheral adaptations of the DOMLEG may underpin these differences.

Efficacy of Virtual Reality Rehabilitation after Spinal Cord Injury: A Systematic Review

Background. Spinal cord injury (SCI) is often associated with long-term impairments related to functional limitations in the sensorimotor system. The use of virtual reality (VR) technology may lead to increased motivation and engagement, besides allowing a wide range of possible tasks/exercises to be implemented in rehabilitation programs. The present review aims to investigate the possible benefits and efficacy of VR-based rehabilitation in individuals with SCI. Methods. An electronically systematic search was performed in multiple databases (PubMed, BVS, Web of Science, Cochrane Central, and Scielo) up to May 2019. MESH terms and keywords were combined in a search strategy. Two reviewers independently selected the studies in accordance with eligibility criteria. The PEDro scale was used to score the methodological quality and risk of bias of the selected studies. Results. Twenty-five studies (including 482 participants, 47.6 ± 9.5 years, 73% male) were selected and discussed. Overall, the studies used VR devices in different rehabilitation protocols to improve motor function, driving skills, balance, aerobic function, and pain level, as well as psychological and motivational aspects. A large amount of heterogeneity was observed as to the study design, VR protocols, and outcome measures used. Only seven studies (28%) had an excellent/good quality of evidence. However, substantial evidence for significant positive effects associated with VR therapy was found in most of the studies (88%), with no adverse events (88%) being reported. Conclusion. Although the current evidence is limited, the findings suggest that VR-based rehabilitation in subjects with SCI may lead to positive effects on aerobic function, balance, pain level, and motor function recovery besides improving psychological/motivational aspects. Further high-quality studies are needed to provide a guideline to clinical practice and to draw robust conclusions about the potential benefits of VR therapy for SCI patients. Protocol details are registered on PROSPERO (registration number: CRD42016052629).

Exercise intolerance in comorbid COPD and heart failure: the role of impaired aerobic function

Impaired aerobic function is a potential mechanism of exercise intolerance in patients with combined cardiorespiratory disease. We investigated the pathophysiological and sensory consequences of a low change in oxygen uptake (ΔV′O2)/change in work rate (ΔWR) relationship during incremental exercise in patients with coexisting chronic obstructive pulmonary disease (COPD) and systolic heart failure (HF).After clinical stabilisation, 51 COPD–HF patients performed an incremental cardiopulmonary exercise test to symptom limitation. Cardiac output was non-invasively measured (impedance cardiography) in a subset of patients (n=18).27 patients presented with ΔV′O2/ΔWR below the lower limit of normal. Despite similar forced expiratory volume in 1 s and ejection fraction, the low ΔV′O2/ΔWR group showed higher end-diastolic volume, lower inspiratory capacity and lower transfer factor compared to their counterparts (p<0.05). Peak WR and peakV′O2were ∼15% and ∼30% lower, respectively, in the former group: those findings were associated with greater symptom burden in daily life and at a given exercise intensity (leg discomfort and dyspnoea). The low ΔV′O2/ΔWR group presented with other evidences of impaired aerobic function (sluggishV′O2kinetics, earlier anaerobic threshold) and cardiocirculatory performance (lower oxygen pulse, lower stroke volume and cardiac output) (p<0.05). Despite similar exertional hypoxaemia, they showed worse ventilatory inefficiency and higher operating lung volumes, which led to greater mechanical inspiratory constraints (p<0.05).Impaired aerobic function due to negative cardiopulmonary–muscular interactions is an important determinant of exercise intolerance in patients with COPD–HF. Treatment strategies to improve oxygen delivery to and/or utilisation by the peripheral muscles might prove particularly beneficial to these patients.

THE EFFECT OF MUSCLE STRENGTH AND AEROBIC FUNCTION IN THE ELDERLY ACCORDING TO EXERCISE LOAD PATTERN USING INDOOR SMALL CYCLING SYSTEM

We were investigating the muscle strength and aerobic function effect on the aged according to active and passive load using compact cycle system. We recruited twenty old participants and they performed shoulder rotating, upper cycling and lower cycling exercise. We measured the muscular activity, respiratory gas analysis and body heat. The result of muscular activity showed that the passive load could cause muscular activity at 15.4–65.9% compared to active load. We thought that the passive exercise could provide the prevention of spasticity and maintain effect of remaining muscle function in the elderly by caused muscular activity over 50%. The result of oxygen consumption showed that it is the active exercise that used the bigger oxygen consumption at 42.4% during lower cycling. We thought that the active exercise used the big muscles of lower limbs including trunk muscles during lower cycling. The result of body temperature showed that it rises with increase in oxygen consumption and heart rate, and it increased the bigger for lower cycling. The foundation of this study could apply to fundamental research for developing exercise load of indoor rehabilitation exercise system with convenience and easy use to the elderly.

Critical power is positively related to skeletal muscle capillarity and type I muscle fibers in endurance-trained individuals

The asymptote [critical power (CP)] and curvature constant ( W′) of the hyperbolic power-duration relationship can predict performance within the severe-intensity exercise domain. However, the extent to which these parameters relate to skeletal muscle morphology is less clear, particularly in endurance-trained individuals, who, relative to their lesser-trained counterparts, possess skeletal muscles that can support high levels of oxygen transport and oxidative capacity, i.e., elevated type I fiber proportion and cross-sectional area (CSA) and capillarity. Fourteen endurance-trained men performed a maximal incremental test to determine peak oxygen uptake (V̇o2peak; 63.2 ± 4.1 ml·min−1·kg−1, mean ± SD) and maximal aerobic power (406 ± 63 W) and three to five constant-load tests to task failure for the determination of CP (303 ± 52 W) and W′ (17.0 ± 3.0 kJ). Skeletal muscle biopsies were obtained from the vastus lateralis and analyzed for percent proportion of fiber types, CSA, and indexes of capillarity. CP was positively correlated with the percent proportion ( r = 0.79; P = 0.001) and CSA ( r = 0.73; P = 0.003) of type I fibers, capillary-to-fiber ratio ( r = 0.88; P < 0.001), and capillary contacts around type I fibers ( r = 0.94; P < 0.001) and type II fibers ( r = 0.68; P = 0.008). W′ was not correlated with any morphological variables. These data reveal a strong positive association between CP and skeletal muscle capillarity. Our findings support the assertion that CP is an important parameter of aerobic function and offer novel insights into the physiological bases of CP. NEW & NOTEWORTHY This investigation demonstrated very strong positive correlations between critical power and skeletal muscle capillarity, particularly around type I fibers, and type I fiber composition. These correlations were demonstrated in endurance-trained individuals expected to possess well-adapted skeletal muscles, such as high levels of oxygen transport structures and high oxidative capacities, supporting the view that critical power is an important parameter of aerobic function. In contrast, the curvature constant W′ was not associated with fiber type composition or capillarity.