Article
Physiology
Bernard Korzeniewski
Summary: This study used a computer model to investigate the Pi double-threshold mechanism of muscle fatigue and the oxygen uptake (VO2) increase in ramp-incremental exercise. It was found that compared to the VO2 slow component in constant-power exercise, the VO2 in ramp-incremental exercise showed a non-linear increase. The higher initiation of additional ATP usage and the lower activity or increased glycolysis stimulation at the highest power outputs in ramp-incremental exercise can explain the smaller or zero non-linearity in VO2 compared to the VO2 slow component in constant-power exercise.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2023)
Article
Sport Sciences
Matthew J. Davies, Gemma K. Lyall, Alan P. Benson, Daniel T. Cannon, Karen M. Birch, Harry B. Rossiter, Carrie Ferguson
Summary: The study found that a slower rate of RI exercise leads to longer tolerable duration. Additionally, at intolerance, RI peak power decreases with lower rates. Furthermore, neuromuscular fatigue in RI-50 and RI-25 may contribute to a reduction in P-iso, limiting exercise performance.
MEDICINE AND SCIENCE IN SPORTS AND EXERCISE
(2021)
Article
Sport Sciences
Kevin Caen, Jan G. Bourgois, Lena Stuer, Vincent Mermans, Jan Boone
Summary: This study examined the suitability of a single ramp incremental test to accurately predict critical power (CP) and W' values. The results showed that the power output (PO) at the respiratory compensation point (RCP) corresponded to CP, and W0 could be calculated from the work done above RCP. However, due to the underestimation and large variability of W' in ramp exercise, the interchangeable use of CP and W' values derived from constant load and ramp exercise is not recommended, especially when accurate estimates or performance predictions are desired.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2023)
Article
Physiology
Christopher B. Cooper, Alan Garfinkel
Summary: The kinetic response of oxygen uptake to transitions of exercise intensity is an important parameter of aerobic function. A novel geometric method is developed to determine the time constant of oxygen uptake using slopes and intercepts of a plot of cumulative oxygen uptake versus time, without requiring multiple repetitions of the exercise protocol.
JOURNAL OF APPLIED PHYSIOLOGY
(2022)
Article
Physiology
Adam Mcdermott, Aaron Nevin, Norita Gildea, Joel Rocha, Donal O'Shea, Mikel Egana
Summary: The purpose of this study was to explore profiles of fractional oxygen extraction during ramp incremental cycling in older individuals with type 2 diabetes. The findings suggest that older individuals with uncomplicated type 2 diabetes demonstrate greater fractional oxygen extraction for a given absolute power output compared with older controls. This may contribute to the reductions in peak oxygen uptake observed in older people with type 2 diabetes.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Physiology
Max E. Weston, Alan R. Barker, Owen W. Tomlinson, Jeff S. Coombes, Tom G. Bailey, Bert Bond
Summary: The study found that children had smaller increases in cerebral blood flow during exercise compared to adolescents and adults, and their respiratory efficiency was lower. Additionally, the regulatory role of end-tidal CO2 on cerebral blood flow during exercise strengthened as age increased.
JOURNAL OF APPLIED PHYSIOLOGY
(2021)
Article
Sport Sciences
Gustavo Z. Schaun, Cristine L. Alberton, Maria Laura B. Gomes, Lucas P. Santos, Marcas M. Bamman, Graciele F. Mendes, Mariana S. Hafele, Luana S. Andrade, Leonardo Alves, Vinicius A. De Ataides, Marco A. Carmona, Rafael Lazaro, Cintia E. Botton, Daniel Umpierre, Stephanie S. Pinto, Eurico N. Wilhelm
Summary: In sedentary older individuals with hypertension, VO2max assessed through GXT may be underestimated, while VER can help validate VO2max and improve accuracy.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2021)
Article
Nutrition & Dietetics
Austin T. Beever, Andrea Y. Zhuang, Saied Jalal Aboodarda, Juan M. Murias, Martin J. MacInnis
Summary: Hypoxia has a negative impact on aerobic exercise, but exercise testing in hypoxic conditions has not been extensively studied. This research investigated the effects of simulated altitude on gas exchange threshold, respiratory compensation point, and maximal oxygen uptake. The findings suggest that mild simulated altitude affects maximal oxygen uptake and peak power output significantly, while gas exchange threshold and respiratory compensation point remain unchanged. Moderate altitude decreases all four variables.
APPLIED PHYSIOLOGY NUTRITION AND METABOLISM
(2022)
Article
Physiology
Gil Bourgois, Alessandro L. L. Colosio, Kevin Caen, Jan G. G. Bourgois, Patrick Mucci, Jan Boone
Summary: This study aimed to investigate the effects of acute heat exposure on respiratory and lactate thresholds in two commonly used incremental exercise test protocols. The results showed that lactate thresholds decreased in hot conditions, while respiratory thresholds remained relatively stable. There was also considerable individual variation in the sensitivity to heat exposure.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2022)
Review
Sport Sciences
Richie P. P. Goulding, Mark Burnley, Rob C. I. Wust
Summary: The priming effect, which refers to the observation that prior heavy or severe-intensity exercise speeds overall oxygen uptake kinetics, has been extensively studied and its underlying mechanisms debated. This review examines the evidence for and against factors such as lactic acidosis, increased muscle temperature, oxygen delivery, altered motor unit recruitment patterns, and enhanced intracellular oxygen utilization in contributing to the priming effect. While lactic acidosis and increased muscle temperature are unlikely key factors, alterations in motor unit recruitment patterns and enhanced intracellular oxygen utilization appear to play important roles.
Article
Physiology
Richie P. Goulding, Dai Okushima, Yoshiyuki Fukuoka, Simon Marwood, Narihiko Kondo, David C. Poole, Thomas J. Barstow, Shunsaku Koga
Summary: The study found that during exercise in the supine position, there is an increase in deoxygenation in superficial muscles, but the deep muscles maintain a stable level of deoxygenation. This suggests that deep muscles are able to defend the balance between oxygen delivery and utilization against reduced perfusion pressure during supine exercise.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2021)
Article
Sport Sciences
Giovanni Baldassarre, Valeria Azzini, Lucrezia Zuccarelli, Cristina Degano, Francesco Graniero, Gloria Plett, Mirco Floreani, Stefano Lazzer, Lucio Mos, Bruno Grassi
Summary: The decrease in work rate at a fixed heart rate during exercise was found to be attenuated in cardiac patients treated with beta-blockers. This phenomenon may indicate impaired exercise tolerance and interfere with exercise prescription.
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2023)
Article
Physiology
Bernard Korzeniewski
Summary: Simulations using a computer model suggest that the slow decrease in VO2 during the second step of two-step incremental exercise can be explained by a decrease in oxidative phosphorylation stimulation and/or an increase in glycolysis stimulation in skeletal muscles. This may be due to the recruitment of more glycolytic fibers or metabolic regulation in already recruited fibers. These predictions can be tested experimentally. No additional data are available.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2023)
Article
Environmental Sciences
Adam Runacres, Kelly Mackintosh, Tim Evans, Melitta A. McNarry
Summary: While the number of adolescents participating in exercise and sports has increased globally, there are still questions about how growth, maturation, and sex influence training response during adolescence. This study found that boys, regardless of training status, had a higher peak oxygen uptake than girls, and muscle deoxygenation seemed to play a more important role in determining this difference.
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
(2022)
Article
Sport Sciences
Carlo Ferri Marini, Luca Correale, Vittoria Carnevale Pellino, Ario Federici, Matteo Vandoni, Francesco Lucertini
Summary: This article introduces a simple and ready-to-use spreadsheet for creating individualized walking, running, and cycling maximal graded exercise test protocols. The procedures in the spreadsheet are based on validated protocols, providing a time-saving, practical, and useful tool.
STRENGTH AND CONDITIONING JOURNAL
(2021)
Article
Critical Care Medicine
Stefanie E. Mason, Rafael Moreta-Martinez, Wassim W. Labaki, Matthew J. Strand, Elizabeth A. Regan, Jessica Bon, Ruben San Jose Estepar, Richard Casaburi, Merry-Lynn McDonald, Harry B. Rossiter, Barry Make, Mark T. Dransfield, MeiLan K. Han, Kendra Young, Jeffrey L. Curtis, Kathleen Stringer, Greg Kinney, John E. Hokanson, Raul San Jose Estepar, George R. Washko
Summary: The longitudinal loss of fat-free mass (FFM) is associated with increased all-cause mortality, regardless of initial body composition metrics, including BMI or muscle mass. This finding may improve risk stratification and identify novel therapeutic targets for patients with chronic obstructive pulmonary disease.
Article
Cardiac & Cardiovascular Systems
David M. Macdonald, Elise F. Palzer, Asghar Abbasi, Arianne K. Baldomero, Surya P. Bhatt, Richard Casaburi, John E. Connett, Mark T. Dransfield, Nathaniel T. Gaeckle, Takudzwa Mkorombindo, Harry B. Rossiter, William W. Stringer, Nicholas B. Tiller, Chris H. Wendt, Dongxing Zhao, Ken M. Kunisaki
Summary: Heart rate measures derived from 6MWT tests may be useful in predicting the risk of acute respiratory events and exacerbations of COPD.
RESPIRATORY MEDICINE
(2022)
Article
Respiratory System
Richard Casaburi, Debora D. Merrill, Gale Harding, Nancy Kline Leidy, Harry B. Rossiter, Ruth Tal-Singer, Alan Hamilton
Summary: The Chronic Lung Disease Biomarker and Clinical Outcome Assessment Qualification Consortium evaluates exercise endurance as a potential outcome measure for drug development trials in chronic obstructive pulmonary disease (COPD). The endurance time increase in constant work rate cycle ergometry is proposed as a key efficacy endpoint in clinical trials.
CHRONIC OBSTRUCTIVE PULMONARY DISEASES-JOURNAL OF THE COPD FOUNDATION
(2022)
Letter
Physiology
Richie P. Goulding, Harry B. Rossiter, Simon Marwood, Carrie Ferguson
EXERCISE AND SPORT SCIENCES REVIEWS
(2022)
Article
Physiology
Min Cao, Robert A. Calmelat, Peter Kierstead, Nicolo Carraro, William W. Stringer, Janos Porszasz, Richard Casaburi, Harry B. Rossiter
Summary: Exercise intolerance in COPD is associated with dyspnea and reduced inspiratory capacity. Combination bronchodilator therapy did not improve neuromuscular performance or increase exercise tolerance in COPD patients.
JOURNAL OF APPLIED PHYSIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Bernard Korzeniewski, Harry B. Rossiter
Summary: This article presents the biochemical basis of exercise intensity domains, focusing on the Pi double-threshold mechanism of muscle fatigue and the role of ATP usage activity. It explores the origins and borders of moderate, heavy, very heavy, and severe exercise intensity and examines the impact of training status on these borders.
BIOSCIENCE REPORTS
(2022)
Article
Neurosciences
Andrea M. Pilotto, Alessandra Adami, Raffaele Mazzolari, Lorenza Brocca, Emanuela Crea, Lucrezia Zuccarelli, Maria A. Pellegrino, Roberto Bottinelli, Bruno Grassi, Harry B. Rossiter, Simone Porcelli
Summary: The final steps of the O-2 cascade during exercise depend on the product of the microvascular-to-intramyocyte PO2 difference and muscle O-2 diffusing capacity (DmO(2)). Non-invasive methods to determine DmO(2) in humans are currently unavailable. Muscle oxygen uptake (m.VO2) recovery rate constant (k), measured by near-infrared spectroscopy (NIRS) using intermittent arterial occlusions, is associated with muscle oxidative capacity in vivo.
JOURNAL OF PHYSIOLOGY-LONDON
(2022)
Article
Respiratory System
Divya Mohan, Harry Rossiter, Henrik Watz, Charles Fogarty, Rachael A. Evans, William Man, Maggie Tabberer, Misba Beerahee, Subramanya Kumar, Helen Millns, Sebin Thomas, Ruth Tal-Singer, Alan J. Russell, Marie Claire Holland, Chika Akinseye, David Neil, Michael Polkey
Summary: In this study, the effects of a selective androgen receptor modulator, GSK2881078, on leg strength in patients with chronic obstructive pulmonary disease (COPD) were investigated. The results showed that GSK2881078 increased leg strength in male COPD patients, but had no significant effect on female patients. The study also found that the use of GSK2881078 was associated with reversible side effects, such as reductions in high-density lipoprotein cholesterol and transient elevations in hepatic transaminases.
Article
Sport Sciences
Nicholas B. Tiller, Janos Porszasz, Richard Casaburi, Harry B. Rossiter, Carrie Ferguson
Summary: Several studies suggest that pulmonary oxygen uptake (V?O-2) at the respiratory compensation point (RCP) is equivalent to the V?O-2 at critical power (CP), which indicates that these variables can be used interchangeably. This study aimed to compare V?O-2 at CP with V?O-2 at RCP in patients with chronic obstructive pulmonary disease (COPD).
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2023)
Review
Physiology
Camilla R. Illidi, Lee M. Romer, Michael A. Johnson, Neil C. Williams, Harry B. Rossiter, Richard Casaburi, Nicholas B. Tiller
Summary: Respiratory function has become a global health priority due to the impact of chronic respiratory disease and the COVID-19 pandemic. The increasing interest in respiratory health has led to a wide range of commercial interventions, some of which have questionable claims and lack regulation. This review aims to help health and exercise professionals differentiate between science and pseudoscience by examining various commercial interventions for their plausibility and comparing them with published literature.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Correction
Physiology
Camilla R. Illidi, Lee M. Romer, Michael A. Johnson, Neil C. Williams, Harry B. Rossiter, Richard Casaburi, Nicholas B. Tiller
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Sport Sciences
Simone Porcelli, Andrea m. Pilotto, Harry b. Rossiter
MEDICINE & SCIENCE IN SPORTS & EXERCISE
(2023)
Meeting Abstract
Physiology
Harry Rossiter, Asghar Abbasi, Juozas Gordevicius, Robert Brooke, Joseph Zoller, Lauren Koch, Steven Britton, Steve Horvath
Article
Engineering, Biomedical
Jiaobing Tu, Jihong Min, Yu Song, Changhao Xu, Jiahong Li, Jeff Moore, Justin Hanson, Erin Hu, Tanyalak Parimon, Ting-Yu Wang, Elham Davoodi, Tsui-Fen Chou, Peter Chen, Jeffrey J. Hsu, Harry B. Rossiter, Wei Gao
Summary: A wearable electrochemical patch has been developed to monitor the biomarker C-reactive protein in sweat in real-time, allowing for point-of-care monitoring in patients with acute or chronic inflammation. The patch integrates various components such as iontophoretic sweat extraction, microfluidic channels for sampling and reagent routing, and a graphene-based sensor array for quantifying CRP and calibrating the sensor with ionic strength, pH, and temperature. The patch showed good correlation with serum protein levels in patients with chronic diseases.
NATURE BIOMEDICAL ENGINEERING
(2023)
Article
Physiology
Asghar Abbasi, Khadije Ahmad, Carrie Ferguson, April Soriano, Robert Calmelat, Harry B. Rossiter, Richard Casaburi, William W. Stringer, Janos Porszasz
Summary: This study examined the effects of using an in-line filter on physiological variables during cardio-pulmonary exercise testing (CPET). The results showed that using the filter only increased minute ventilation and tidal volume, while having little effect on metabolic rate. Therefore, using an in-line filter is feasible and may reduce the risk of aerosol dispersion during CPET.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2023)