Dataset Information

Supra-Versus Submaximal Cycle Ergometer Verification of VO_2max in Males and Females.

ABSTRACT: This study was designed to determine the optimal intensity for verification phase testing (VP) in healthy, young adults. Thirty one young, active participants (16 females) completed a cycle ergometer graded exercise test (GXT) VO_2max test and 4 VP tests at 80, 90, 100, and 105% of the maximum wattage achieved during the GXT. GXT and VP VO_2max values showed a significant test x sex interaction (p = 0.02). The males elicited significantly higher VO_2max values during the GXT, 80%, and 90% when compared to the 105%, (105 vs. GXT: p = 0.05; 105% vs. 80%: p < 0.01; 105% vs. 90%: p = 0.02). There were no significant differences in VO_2max across the tests in the females (p > 0.05); 80% of the males achieved their highest VP VO_2max during a submaximal VP test compared to only 37.5% of the females. A secondary study conducted showed excellent reliability (ICCs > 0.90) and low variation (CVs < 3%) for the 90% VP. Our findings show that a submaximal verification phase intensity is ideal for young healthy males to elicit the highest VO_2max during cycle ergometer testing. For females, a range of intensities (80-105%) produce similar VO_2max values. However, the 80% VP yields an unnecessarily high time to exhaustion.

SUBMITTER: Sawyer BJ

PROVIDER: S-EPMC7764640 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Supra-Versus Submaximal Cycle Ergometer Verification of VO2max in Males and Females.

Sawyer Brandon J BJ McMahon Nicholas N Thornhill Kirsten L KL Baughman Brett R BR Mahoney Jenny M JM Pattison Kai L KL Freeberg Kaitlin A KA Botts Ryan T RT

Sports (Basel, Switzerland) 20201212 12

This study was designed to determine the optimal intensity for verification phase testing (VP) in healthy, young adults. Thirty one young, active participants (16 females) completed a cycle ergometer graded exercise test (GXT) VO2max test and 4 VP tests at 80, 90, 100, and 105% of the maximum wattage achieved during the GXT. GXT and VP VO2max values showed a significant test x sex interaction (p = 0.02). The males elicited significantly higher VO2max value ...[more]

PMID: 33322835

Similar Datasets

Project description:Cycle ergometer training (CET) has been shown to improve exercise performance of the quadriceps muscles in patients with COPD, and inspiratory muscle training (IMT) may improve the pressure-generating capacity of the inspiratory muscles. However, the effects of combined CET and IMT remain unclear and there is a lack of comprehensive assessment.Eighty-one patients with COPD were randomly allocated to three groups: 28 received 8 weeks of CET + IMT (combined training group), 27 received 8 weeks of CET alone (CET group), and 26 only received 8 weeks of free walking (control group). Comprehensive assessment including respiratory muscle strength, exercise capacity, pulmonary function, dyspnea, quality of life, emotional status, nutritional status, and body mass index, airflow obstruction, and exercise capacity index were measured before and after the pulmonary rehabilitation program.Respiratory muscle strength, exercise capacity, inspiratory capacity, dyspnea, quality of life, depression and anxiety, and nutritional status were all improved in the combined training and CET groups when compared with that in the control group (P<0.05) after pulmonary rehabilitation program. Inspiratory muscle strength increased significantly in the combined training group when compared with that in the CET group (?PImax [maximal inspiratory pressure] 5.20±0.89 cmH2O vs 1.32±0.91 cmH2O; P<0.05). However, there were no significant differences in the other indices between the two groups (P>0.05). Patients with weakened respiratory muscles in the combined training group derived no greater benefit than those without respiratory muscle weakness (P>0.05). There were no significant differences in these indices between the patients with malnutrition and normal nutrition after pulmonary rehabilitation program (P>0.05).Combined training is more effective than CET alone for increasing inspiratory muscle strength. IMT may not be useful when combined with CET in patients with weakened inspiratory muscles. Nutritional status had slight impact on the effects of pulmonary rehabilitation. A comprehensive assessment approach can be more objective to evaluate the effects of combined CET and IMT.

Project description:Transmission is a matter of life or death for pathogen lineages and can therefore be considered as the main motor of their evolution. Gammaherpesviruses are archetypal pathogenic persistent viruses which have evolved to be transmitted in presence of specific immune response. Identifying their mode of transmission and their mechanisms of immune evasion is therefore essential to develop prophylactic and therapeutic strategies against these infections. As the known human gammaherpesviruses, Epstein-Barr virus and Kaposi's Sarcoma-associated Herpesvirus are host-specific and lack a convenient in vivo infection model; related animal gammaherpesviruses, such as murine gammaherpesvirus-68 (MHV-68), are commonly used as general models of gammaherpesvirus infections in vivo. To date, it has however never been possible to monitor viral excretion or virus transmission of MHV-68 in laboratory mice population. In this study, we have used MHV-68 associated with global luciferase imaging to investigate potential excretion sites of this virus in laboratory mice. This allowed us to identify a genital excretion site of MHV-68 following intranasal infection and latency establishment in female mice. This excretion occurred at the external border of the vagina and was dependent on the presence of estrogens. However, MHV-68 vaginal excretion was not associated with vertical transmission to the litter or with horizontal transmission to female mice. In contrast, we observed efficient virus transmission to naïve males after sexual contact. In vivo imaging allowed us to show that MHV-68 firstly replicated in penis epithelium and corpus cavernosum before spreading to draining lymph nodes and spleen. All together, those results revealed the first experimental transmission model for MHV-68 in laboratory mice. In the future, this model could help us to better understand the biology of gammaherpesviruses and could also allow the development of strategies that could prevent the spread of these viruses in natural populations.

Project description:Background: Women are twice as likely as men to develop major depression. The brain mechanisms underlying this sex disparity are not clear. Disruption of the glutamate-glutamine cycle has been implicated in psychiatric disturbances. This study identifies sex-based impairments in the glutamate-glutamine cycle involving astrocytes using an animal model of depression. Methods: Male and female adult Long-Evans rats were exposed to chronic social defeat stress (CSDS) for 21 days, using a modified resident-intruder paradigm. Territorial aggression was used for males and maternal aggression was used for females to induce depressive-like deficits for intruders. The depressive-like phenotype was assessed with intake for saccharin solution, weight gain, estrous cycle, and corticosterone (CORT). Behaviors displayed by the intruders during daily encounters with residents were characterized. Rats with daily handling were used as controls for each sex. Ten days after the last encounter, both the intruders and controls were subjected to a no-net-flux in vivo microdialysis to assess glutamate accumulation and extracellular glutamine in the nucleus accumbens (NAc). The contralateral hemispheres were used for determining changes in astrocytic markers, including glial fibrillary acidic protein (GFAP) and glutamate transporter-1 (GLT-1). Results: Both male and female intruders reduced saccharin intake over the course of CSDS, compared to their pre-stress period and to their respective controls. Male intruders exhibited submissive/defensive behaviors to territorial aggression by receiving sideways threats and bites. These males showed reductions in striatal GLT-1 and spontaneous glutamine in the NAc, compared to controls. Female intruders exhibited isolated behaviors to maternal aggression, including immobility, rearing, and selfgrooming. Their non-reproductive days were extended. Also, they showed reductions in prefrontal and accumbal GFAP+ cells and prefrontal GLT-1, compared to controls. When 10 μM of glutamate was infused, these females showed a significant accumulation of glutamate compared to controls. Infusions of glutamate reduced extracellular glutamine for both male and female intruders compared to their respective controls. Conclusion: Twenty-one days of territorial or maternal aggression produced a depressive-like phenotype and impaired astrocytes in both male and female intruders. Disruption of the glutamate-glutamine cycle in the PFC-striatal network may be linked to depressive-like deficits more in females than in males.

Dataset Information

Supra-Versus Submaximal Cycle Ergometer Verification of VO_2max in Males and Females.

Publications

Supra-Versus Submaximal Cycle Ergometer Verification of VO<sub>2max</sub> in Males and Females.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets