A single bout of aerobic exercise improves executive function; however, the mechanism for the improvement remains unclear. One proposal asserts that an exercise-mediated increase in cerebral blood flow (CBF) enhances the efficiency of executive-related cortical structures. Here, participants completed separate 10-min sessions of moderate to heavy intensity aerobic exercise, a hypercapnic environment (i.e., 5% CO2), and a non-exercise and non-hypercapnic control condition. The hypercapnic condition was included because it produces an increase in CBF independent of metabolic demands. An estimate of CBF was achieved via transcranial doppler ultrasound and near-infrared spectroscopy that provided measures of middle cerebral artery blood velocity (BV) and deoxygenation (HHb), respectively. Exercise intensity was adjusted to match participant-specific change in BV and HHb associated with the hypercapnic condition. Executive function was assessed prior to and after each session via antisaccades (i.e., saccade mirror-symmetrical to a target) because the task is mediated via the same executive networks that demonstrate task-dependent modulation following single- and chronic-bouts of aerobic exercise. Results showed that hypercapnic and exercise conditions were associated with comparable BV and HHb changes, whereas the control condition did not produce a change in either metric. In terms of antisaccade performance, the exercise and hypercapnic - but not control - conditions demonstrated improved post-condition reaction times (RT), and the magnitude of the hypercapnic and exercise-based increase in estimated CBF was reliably related to the post-condition improvement in RT. Accordingly, results evince that an increase in CBF represents a reliable candidate for a post-exercise improvement in executive function.

Introduction: Radiation therapy increases the risk of secondary malignancy and morbidity in cancer survivors. The role of obesity and exercise training in modulating this risk is not well understood. As such, we used a preclinical model of radiation-induced malignancy to investigate whether diet-induced obesity and/or endurance exercise training altered lifelong survival, cancer incidence, and morbidity. Methods: Male CBA mice were randomly divided into control diet/sedentary group (CTRL/SED), high-fat diet (45% fat)/sedentary group (HFD/SED), control diet/exercise group (2-3 d•wk −1 ; CTRL/EX), or high-fat diet/exercise group (HFD/EX) groups then exposed to whole-body radiation (3 Gy). End point monitoring and pathology determined mortality and cancer incidence, respectively. Health span index, a measure of morbidity, was determined by a composite measure of 10 anthropometric, metabolic, performance, and behavioral measures. Results: Overall survival was higher in HFD/SED compared with CTRL/SED (P < 0.05). The risk of cancer-related mortality by 18 months postradiation was 1.99 and 1.63 in HFD/SED compared with CTRL/EX (RR = 1.99, 95% confidence interval = 1.20-3.31, P = 0.0081) and CTRL/SED (RR = 1.63, 95% confidence interval = 1.06-2.49, P = 0.0250), respectively. The number of mice at end point with cancer was higher in HFD/SED compared with CTRL/EX and CTRL/SED (P < 0.05). Health span index was highest in CTRL/EX (score = +2.5), followed by HFD/EX (score = +1), and HFD/SED (score = −1) relative to CTRL/SED. Conclusion: This work provides the basis for future preclinical studies investigating the dose-response relationship between exercise training and late effects of radiation therapy as well as the mechanisms responsible for these effects.

Introduction: Post-chemotherapy residual masses (PCRMs) may contain persistent cancer or teratoma in more than 50% of patients with metastatic non-seminomatous germ cell tumours (mNSGCTs). Retroperitoneal lymph node dissection (RPLND) is curative, but controversy exists about selection criteria for surgery. A validated prediction model by Vergouwe et al (2007) based on over 1000 patients was evaluated at our centre. Methods: mNSGCT patients treated with RPLND for PCRMs were identified from an electronic database. Typographical errors in the model were identified and corrected using their 2003 publication, but retaining the 2007 coefficients. Six clinical variables were included in the model and the calculated probability of benign tissue was compared with pathology. "Benign tissue only" was considered a positive test outcome in patients with a predicted probability of "benign tissue only" greater than 70%. Results: Fifty-two (52) mNSGCT patients between 1980 and 2014 were evaluable. Median age was 32 years (range 17-52) and International Germ Cell Consensus Classification (IGCCC) prognostic stages were: good 46.2%, intermediate 32.7%, and poor 21.2%. Most patients received bleomycin/etoposide/cisplatin (BEP) chemotherapy and full bilateral RPLND. Pathology showed residual cancer or teratoma in 31 patients (59.6%) and benign findings in 21 patients (40.6%). Positive and negative predictive values and accuracy were 100%, 69%, and 73%, respectively. Conclusions: "Benign tissue only" was found in 100% of patients in whom this was predicted using our pre-determined criteria. This study involved a limited number of patients, but confirms the potential value of the Vergouwe et al model. Routine use of this prediction model in clinical practice should be tested for mNSGCT patients with PCRMs.

Weight loss and exercise reduce colorectal cancer (CRC) risk in persons with obesity. Whether weight loss and exercise effect myofibre characteristics and muscle stem/progenitor cell populations in mice with preneoplastic colorectal lesions, a model of CRC risk, is unknown. To address this gap, male C57Bl/6J mice were fed a high-fat diet (HFD) to induce obesity or a control (CON) diet prior to azoxymethane injection to induce preneoplastic colorectal lesions. The HFD group was then randomized to weight loss conditions that included (1) switching to the CON diet only (HFD-SED) or switching to the CON diet with treadmill exercise training (HFD-EX). Average myofibre cross-sectional area was not different between groups. There were more smaller-sized fibers in HFD-EX (p<0.05 vs. CON), and more fibrosis in HFD-SED (p<0.05 vs. HFD-EX and CON). There was a trend for more committed (Pax7+MyoD+) myoblasts (p=0.059) and more fibro-adipogenic progenitors (FAPs) in HFD-EX (p<0.05 vs. CON). Additionally, the canonical pro-inflammatory marker p-NF-κB, was markedly reduced in the insterstitium of HFD-EX (p<0.05 vs. CON and HFD-SED). Our findings suggest that in mice with preneoplastic colorectal lesions, HFD followed by weight loss with exercise, reduces muscle fibrosis and results in a higher content of muscle stem/progenitor cells. Novelty Bullets: • Exercise improves muscle architecture in mice with preneoplastic colorectal lesion • Exercise increases fibro/adipogenic progenitors and reduces inflammatory signaling in mice with preneoplastic colorectal lesions